docs: add missing XML doc comments across gateway, worker, and .NET client

Resolves 1113 documentation-completeness gaps flagged by CommentChecker (MissingReturns, MissingInheritDoc, InheritDocMisused, MissingDoc, MissingParam, RedundantInheritDoc) so the API surface is fully documented and the analyzer scan is clean. Doc comments only; no code changes.
chore(dashboard): prune dead sidebar + orphaned login CSS from site.css
2026-06-03 12:33:53 -04:00 · 2026-06-03 04:37:23 -04:00 · 2026-06-03 03:56:51 -04:00 · 2026-06-03 03:51:45 -04:00 · 2026-06-03 03:49:34 -04:00 · 2026-06-03 03:46:37 -04:00
783 changed files with 42786 additions and 19037 deletions
@@ -45,6 +45,7 @@ build/
 out/
 tmp/
 temp/
+install/

 # .NET
 **/bin/
@@ -146,3 +147,8 @@ generated-scratch/

 # Keep empty directories with .gitkeep files when needed
 !.gitkeep
+
+# Documentation review artifacts (CommentChecker output)
+*-docs-issues.md
+*-docs-fixed.md
+*-docs-final.md
@@ -32,7 +32,7 @@ dotnet test src/MxGateway.Worker.Tests/MxGateway.Worker.Tests.csproj -p:Platform
 dotnet run --project src/MxGateway.Server/MxGateway.Server.csproj

 # API-key admin CLI (same exe, "apikey" subcommand)
-dotnet run --project src/MxGateway.Server/MxGateway.Server.csproj -- apikey create --display-name "dev" --scopes session:open,session:close,invoke:read,invoke:write,invoke:secure,events:read,metadata:read,admin
+dotnet run --project src/MxGateway.Server/MxGateway.Server.csproj -- apikey create --display-name "dev" --scopes session,invoke,event,metadata,admin
 ```

 Single test by name (xUnit `--filter`):
@@ -100,7 +100,7 @@ When source code changes, build and test the affected component before reporting
 ## Design Sources To Consult Before Non-Trivial Changes

 - `gateway.md` — top-level architecture, command/event surface, IPC envelope, STA thread model, fault handling.
- `glauth.md` — local LDAP server (GLAuth on `localhost:3893`, base DN `dc=lmxopcua,dc=local`) used for dev authn. Pre-provisioned users (`admin/admin123`, `readonly/readonly123`, etc.) and the role→capability mapping live there.
+- `glauth.md` — local LDAP server (GLAuth on `localhost:3893`, base DN `dc=zb,dc=local`) used for dev authn. Pre-provisioned users (`admin/admin123`, `readonly/readonly123`, etc.) and the role→capability mapping live there.
 - `docs/DesignDecisions.md` — v1 choices (MXAccess COM target `LMXProxyServerClass` from `C:\Program Files (x86)\ArchestrA\Framework\Bin\ArchestrA.MXAccess.dll`, API-key-in-SQLite auth, fail-fast event backpressure, etc.).
 - `docs/GatewayProcessDesign.md`, `docs/MxAccessWorkerInstanceDesign.md`, `docs/WorkerFrameProtocol.md`, `docs/WorkerProcessLauncher.md` — detailed component designs.
 - `docs/GatewayConfiguration.md` — full `MxGateway:*` options bound by `GatewayOptions` and validated at startup by `GatewayOptionsValidator`.
@@ -114,9 +114,9 @@ External analysis sources referenced by design docs:

 ## Authentication

-Gateway gRPC clients authenticate with an API key in metadata: `authorization: Bearer mxgw_<key-id>_<secret>`. Keys are stored hashed (with a peppered SHA) in a gateway-owned SQLite DB (default `C:\ProgramData\MxGateway\gateway-auth.db`). Scopes (`session:open`, `session:close`, `invoke:read`, `invoke:write`, `invoke:secure`, `events:read`, `metadata:read`, `admin`) gate specific RPCs; missing → `Unauthenticated`, insufficient → `PermissionDenied`. The `apikey` subcommand on the server exe manages keys; see `src/MxGateway.Server/Security/Authentication/`.
+Gateway gRPC clients authenticate with an API key in metadata: `authorization: Bearer mxgw_<key-id>_<secret>`. Keys are stored hashed (with a peppered SHA) in a gateway-owned SQLite DB (default `C:\ProgramData\MxGateway\gateway-auth.db`). Scopes (`session`, `invoke`, `event`, `metadata`, `admin`) gate specific RPCs; missing → `Unauthenticated`, insufficient → `PermissionDenied`. The `apikey` subcommand on the server exe manages keys; see `src/MxGateway.Server/Security/Authentication/`.

-Dashboard auth uses the same verifier but exchanges the API key for an HTTP-only secure cookie at `/dashboard/login`. `Dashboard:AllowAnonymousLocalhost` bypasses cookie auth on loopback when explicitly enabled.
+Dashboard auth is LDAP-backed (separate from the gRPC API-key model). `/login` binds against `MxGateway:Ldap` and maps the user's LDAP groups to `Admin` or `Viewer` via `MxGateway:Dashboard:GroupToRole`, then issues an HTTP-only secure `__Host-MxGatewayDashboard` cookie. SignalR hubs at `/hubs/{snapshot,alarms,events}` accept either the cookie or a 30-minute bearer minted at `/hubs/token`. `Dashboard:AllowAnonymousLocalhost` bypasses auth on loopback when enabled.

 ## Process / Platform Notes

@@ -3,15 +3,15 @@
 This document describes how to perform a comprehensive, per-module code review of
 the `mxaccessgw` codebase and how to track findings to resolution.

-A **module** is one buildable project under `src/` (e.g. `src/MxGateway.Worker`)
+A **module** is one buildable project under `src/` (e.g. `src/ZB.MOM.WW.MxGateway.Worker`)
 or one language client under `clients/` (e.g. `clients/rust`). Each module has
 its own folder under `code-reviews/` containing a single `findings.md`.

 ## 1. Before you start

 1. Pick the module to review. Its folder is `code-reviews/<Module>/`:
-   - For a `src/` project, `<Module>` is the project name with the `MxGateway.`
-     prefix stripped — `src/MxGateway.Server` is reviewed in `code-reviews/Server/`.
+   - For a `src/` project, `<Module>` is the project name with the `ZB.MOM.WW.MxGateway.`
+     prefix stripped — `src/ZB.MOM.WW.MxGateway.Server` is reviewed in `code-reviews/Server/`.
   - For a language client, `<Module>` is `Client.<Lang>` — `clients/rust` is
     reviewed in `code-reviews/Client.Rust/`.
 2. Identify the design context for the module:
@@ -65,8 +65,8 @@ means the checklist is completed even where it produces no findings — record
 8. **Code organization & conventions** — namespace hierarchy, project layout, the
   Options pattern, separation of concerns, additive-only contract evolution.
 9. **Testing coverage** — are the module's behaviours covered by tests
-   (`src/MxGateway.Tests`, `src/MxGateway.Worker.Tests`,
-   `src/MxGateway.IntegrationTests`)? Note untested critical paths and missing
+   (`src/ZB.MOM.WW.MxGateway.Tests`, `src/ZB.MOM.WW.MxGateway.Worker.Tests`,
+   `src/ZB.MOM.WW.MxGateway.IntegrationTests`)? Note untested critical paths and missing
   edge-case tests.
 10. **Documentation & comments** — XML doc accuracy, misleading or stale comments,
    undocumented non-obvious behaviour.
@@ -1,17 +1,21 @@
 <Project>
-  <!--
-    Mirrors src/Directory.Build.props for the .NET client projects under
-    clients/dotnet/ so they share the same enforcement floor (warnings-as-
-    errors, latest analyzers, code-style enforcement, deterministic builds)
-    even though they live outside src/.
-  -->
  <PropertyGroup>
-    <LangVersion>latest</LangVersion>
-    <Nullable>enable</Nullable>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
-    <AnalysisLevel>latest</AnalysisLevel>
-    <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
-    <Deterministic>true</Deterministic>
+    <!-- Shared package metadata for clients/dotnet/. Individual projects opt in via <IsPackable>true</IsPackable>. -->
+    <Authors>Joseph Doherty</Authors>
+    <Company>ZB MOM WW</Company>
+    <Copyright>Copyright (c) ZB MOM WW. All rights reserved.</Copyright>
+    <Product>MxAccessGateway Client</Product>
+    <RepositoryUrl>https://gitea.dohertylan.com/dohertj2/mxaccessgw</RepositoryUrl>
+    <RepositoryType>git</RepositoryType>
+    <PackageProjectUrl>https://gitea.dohertylan.com/dohertj2/mxaccessgw</PackageProjectUrl>
+    <PackageTags>mxaccess;mxgateway;grpc;client;archestra</PackageTags>
+    <PackageRequireLicenseAcceptance>false</PackageRequireLicenseAcceptance>
+    <!-- Versioning: bump per release. Symbols ship as snupkg. -->
+    <Version>0.1.0</Version>
+    <IncludeSymbols>true</IncludeSymbols>
+    <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <!-- Default: do NOT pack. Each project opts in. -->
+    <IsPackable>false</IsPackable>
  </PropertyGroup>
 </Project>
@@ -16,9 +16,9 @@ Recommended layout:

 ```text
 clients/dotnet/
-  MxGateway.Client.sln
-  MxGateway.Client/
-    MxGateway.Client.csproj
+  ZB.MOM.WW.MxGateway.Client.slnx
+  ZB.MOM.WW.MxGateway.Client/
+    ZB.MOM.WW.MxGateway.Client.csproj
    GatewayClient.cs
    MxGatewaySession.cs
    MxGatewayClientOptions.cs
@@ -26,14 +26,14 @@ clients/dotnet/
    Conversion/
    Errors/
    Generated/
-  MxGateway.Client.Cli/
-    MxGateway.Client.Cli.csproj
+  ZB.MOM.WW.MxGateway.Client.Cli/
+    ZB.MOM.WW.MxGateway.Client.Cli.csproj
    Program.cs
    Commands/
-  MxGateway.Client.Tests/
-    MxGateway.Client.Tests.csproj
-  MxGateway.Client.IntegrationTests/
-    MxGateway.Client.IntegrationTests.csproj
+  ZB.MOM.WW.MxGateway.Client.Tests/
+    ZB.MOM.WW.MxGateway.Client.Tests.csproj
+  ZB.MOM.WW.MxGateway.Client.IntegrationTests/
+    ZB.MOM.WW.MxGateway.Client.IntegrationTests.csproj
 ```

 Target framework:
@@ -43,7 +43,7 @@ Target framework:
 ```

 The scaffold uses a project reference to
-`src/MxGateway.Contracts/MxGateway.Contracts.csproj` for generated protobuf and
+`src/ZB.MOM.WW.MxGateway.Contracts/ZB.MOM.WW.MxGateway.Contracts.csproj` for generated protobuf and
 gRPC types. `clients/dotnet/generated` remains reserved for client-local
 generator output if the .NET client later needs to decouple from the contracts
 project.
@@ -107,6 +107,7 @@ public sealed class MxGatewayClientOptions
    public required string ApiKey { get; init; }
    public bool UseTls { get; init; }
    public string? CaCertificatePath { get; init; }
+    public bool RequireCertificateValidation { get; init; }
    public string? ServerNameOverride { get; init; }
    public TimeSpan ConnectTimeout { get; init; } = TimeSpan.FromSeconds(10);
    public TimeSpan DefaultCallTimeout { get; init; } = TimeSpan.FromSeconds(30);
@@ -124,6 +125,24 @@ or subscription changes because those calls can partially succeed in MXAccess.
 API key may be loaded from `MXGATEWAY_API_KEY` by the CLI, not implicitly by the
 library constructor unless a helper explicitly says it does that.

+### TLS trust posture
+
+The gateway can serve a self-signed certificate it generates itself (it has no
+PKI). To make that usable, TLS is **lenient by default**: when `UseTls` is set
+and `CaCertificatePath` is empty, `CreateHttpHandler` installs a
+`RemoteCertificateValidationCallback` that returns `true`, so the gateway's
+self-signed certificate is accepted without verification.
+
+To verify the gateway instead:
+
+- set `CaCertificatePath` to pin a CA — validated via a `CustomRootTrust`
+  `X509Chain` against that root, and the callback additionally rejects a
+  hostname/SAN mismatch (`RemoteCertificateNameMismatch`); or
+- set `RequireCertificateValidation` to `true` to keep the default OS/system-trust
+  verification on a connection with no pinned CA.
+
+Pinning a CA always wins over the lenient default.
+
 ## Auth Interceptor

 Use a gRPC call credentials/interceptor layer to attach:
@@ -166,7 +185,7 @@ reply.EnsureMxAccessSuccess();

 ## Test CLI

-Project: `MxGateway.Client.Cli`.
+Project: `ZB.MOM.WW.MxGateway.Client.Cli`.

 Command examples:

@@ -1,76 +0,0 @@
-using Grpc.Core;
-
-namespace MxGateway.Client.Tests;
-
-/// <summary>Tests for the shared gRPC-to-native exception mapping used by the transports.</summary>
-public sealed class RpcExceptionMapperTests
-{
-    /// <summary>Verifies that an unauthenticated status maps to the authentication exception.</summary>
-    [Fact]
-    public void Map_UnauthenticatedStatus_ProducesAuthenticationException()
-    {
-        RpcException rpc = new(new Status(StatusCode.Unauthenticated, "no key"));
-
-        Exception mapped = RpcExceptionMapper.Map(rpc, CancellationToken.None);
-
-        MxGatewayAuthenticationException authentication =
-            Assert.IsType<MxGatewayAuthenticationException>(mapped);
-        Assert.Equal(StatusCode.Unauthenticated, authentication.StatusCode);
-    }
-
-    /// <summary>Verifies that a permission-denied status maps to the authorization exception.</summary>
-    [Fact]
-    public void Map_PermissionDeniedStatus_ProducesAuthorizationException()
-    {
-        RpcException rpc = new(new Status(StatusCode.PermissionDenied, "missing scope"));
-
-        Exception mapped = RpcExceptionMapper.Map(rpc, CancellationToken.None);
-
-        MxGatewayAuthorizationException authorization =
-            Assert.IsType<MxGatewayAuthorizationException>(mapped);
-        Assert.Equal(StatusCode.PermissionDenied, authorization.StatusCode);
-    }
-
-    /// <summary>Verifies that a cancelled status maps to OperationCanceledException.</summary>
-    [Fact]
-    public void Map_CancelledStatus_ProducesOperationCanceledException()
-    {
-        RpcException rpc = new(new Status(StatusCode.Cancelled, "cancelled"));
-
-        Exception mapped = RpcExceptionMapper.Map(rpc, CancellationToken.None);
-
-        Assert.IsType<OperationCanceledException>(mapped);
-    }
-
-    /// <summary>
-    /// Verifies that non-auth statuses surface the originating gRPC status code on the
-    /// mapped exception so callers can distinguish transient from permanent failures
-    /// without reflecting into InnerException.
-    /// </summary>
-    [Theory]
-    [InlineData(StatusCode.NotFound)]
-    [InlineData(StatusCode.InvalidArgument)]
-    [InlineData(StatusCode.ResourceExhausted)]
-    [InlineData(StatusCode.FailedPrecondition)]
-    [InlineData(StatusCode.Unavailable)]
-    [InlineData(StatusCode.Internal)]
-    public void Map_NonAuthStatus_CarriesStatusCodeOnMxGatewayException(StatusCode statusCode)
-    {
-        RpcException rpc = new(new Status(statusCode, "boom"));
-
-        Exception mapped = RpcExceptionMapper.Map(rpc, CancellationToken.None);
-
-        MxGatewayException gatewayException = Assert.IsType<MxGatewayException>(mapped);
-        Assert.Equal(statusCode, gatewayException.StatusCode);
-        Assert.Same(rpc, gatewayException.InnerException);
-    }
-
-    /// <summary>Verifies that an MxGatewayException built without a gRPC status reports a null StatusCode.</summary>
-    [Fact]
-    public void StatusCode_IsNull_WhenNoGrpcStatusProvided()
-    {
-        MxGatewayException gatewayException = new("plain failure");
-
-        Assert.Null(gatewayException.StatusCode);
-    }
-}
@@ -1,76 +0,0 @@
-
-Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 17
-VisualStudioVersion = 17.0.31903.59
-MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MxGateway.Client", "MxGateway.Client\MxGateway.Client.csproj", "{7CF9ED88-1F32-4040-BEB1-D0902E304C70}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MxGateway.Contracts", "..\..\src\MxGateway.Contracts\MxGateway.Contracts.csproj", "{9AB807A8-0469-40F7-A000-D240F36B6E5D}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MxGateway.Client.Cli", "MxGateway.Client.Cli\MxGateway.Client.Cli.csproj", "{EB061E77-2475-4322-9257-3F2456DD141C}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MxGateway.Client.Tests", "MxGateway.Client.Tests\MxGateway.Client.Tests.csproj", "{B77B5A8E-0C53-4419-9BCD-227C9753A074}"
-EndProject
-Global
-	GlobalSection(SolutionConfigurationPlatforms) = preSolution
-		Debug|Any CPU = Debug|Any CPU
-		Debug|x64 = Debug|x64
-		Debug|x86 = Debug|x86
-		Release|Any CPU = Release|Any CPU
-		Release|x64 = Release|x64
-		Release|x86 = Release|x86
-	EndGlobalSection
-	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|x64.Build.0 = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Debug|x86.Build.0 = Debug|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|Any CPU.Build.0 = Release|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|x64.ActiveCfg = Release|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|x64.Build.0 = Release|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|x86.ActiveCfg = Release|Any CPU
-		{7CF9ED88-1F32-4040-BEB1-D0902E304C70}.Release|x86.Build.0 = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|x64.Build.0 = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Debug|x86.Build.0 = Debug|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|Any CPU.Build.0 = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|x64.ActiveCfg = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|x64.Build.0 = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|x86.ActiveCfg = Release|Any CPU
-		{9AB807A8-0469-40F7-A000-D240F36B6E5D}.Release|x86.Build.0 = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|x64.Build.0 = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Debug|x86.Build.0 = Debug|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|Any CPU.Build.0 = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|x64.ActiveCfg = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|x64.Build.0 = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|x86.ActiveCfg = Release|Any CPU
-		{EB061E77-2475-4322-9257-3F2456DD141C}.Release|x86.Build.0 = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|x64.Build.0 = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Debug|x86.Build.0 = Debug|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|Any CPU.Build.0 = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|x64.ActiveCfg = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|x64.Build.0 = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|x86.ActiveCfg = Release|Any CPU
-		{B77B5A8E-0C53-4419-9BCD-227C9753A074}.Release|x86.Build.0 = Release|Any CPU
-	EndGlobalSection
-	GlobalSection(SolutionProperties) = preSolution
-		HideSolutionNode = FALSE
-	EndGlobalSection
-EndGlobal
@@ -1,67 +0,0 @@
-namespace MxGateway.Client;
-
-/// <summary>
-/// Server-side filters and shape options for
-/// <see cref="GalaxyRepositoryClient.DiscoverHierarchyAsync(DiscoverHierarchyOptions, System.Threading.CancellationToken)"/>.
-/// Each property maps directly to the corresponding field on the
-/// <c>DiscoverHierarchyRequest</c> proto so the gateway can narrow the
-/// hierarchy walk before serializing it back to the client.
-/// </summary>
-public sealed record DiscoverHierarchyOptions
-{
-    /// <summary>
-    /// Root Galaxy object id to start the walk from. When set, takes
-    /// precedence over <see cref="RootTagName"/> and <see cref="RootContainedPath"/>.
-    /// </summary>
-    public int? RootGobjectId { get; init; }
-
-    /// <summary>
-    /// Root tag (assigned) name to start the walk from. Used when
-    /// <see cref="RootGobjectId"/> is null.
-    /// </summary>
-    public string? RootTagName { get; init; }
-
-    /// <summary>
-    /// Root contained-name dotted path to start the walk from. Used when
-    /// neither <see cref="RootGobjectId"/> nor <see cref="RootTagName"/> are set.
-    /// </summary>
-    public string? RootContainedPath { get; init; }
-
-    /// <summary>
-    /// Maximum traversal depth below the root, inclusive. Leave null for the
-    /// server default (unbounded).
-    /// </summary>
-    public int? MaxDepth { get; init; }
-
-    /// <summary>
-    /// Galaxy category ids to include. Empty means all categories.
-    /// </summary>
-    public IReadOnlyList<int> CategoryIds { get; init; } = Array.Empty<int>();
-
-    /// <summary>
-    /// Template tag names that must appear somewhere in each returned
-    /// object's template chain. Empty means no template filter.
-    /// </summary>
-    public IReadOnlyList<string> TemplateChainContains { get; init; } = Array.Empty<string>();
-
-    /// <summary>
-    /// Optional glob (e.g. <c>"Tank*"</c>) matched against each object's tag name.
-    /// </summary>
-    public string? TagNameGlob { get; init; }
-
-    /// <summary>
-    /// When set, overrides whether each returned <c>GalaxyObject</c> includes
-    /// its dynamic attribute list. Leave null to use the server default.
-    /// </summary>
-    public bool? IncludeAttributes { get; init; }
-
-    /// <summary>
-    /// When true, restrict results to objects that bear at least one configured alarm.
-    /// </summary>
-    public bool AlarmBearingOnly { get; init; }
-
-    /// <summary>
-    /// When true, restrict results to objects that have at least one historized attribute.
-    /// </summary>
-    public bool HistorizedOnly { get; init; }
-}
@@ -1,19 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <ItemGroup>
-    <ProjectReference Include="..\..\..\src\MxGateway.Contracts\MxGateway.Contracts.csproj" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Grpc.Net.Client" Version="2.76.0" />
-    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.7" />
-    <PackageReference Include="Polly.Core" Version="8.6.6" />
-  </ItemGroup>
-
-  <PropertyGroup>
-    <TargetFramework>net10.0</TargetFramework>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
-  </PropertyGroup>
-
-</Project>
@@ -1,25 +0,0 @@
-using MxGateway.Contracts;
-
-namespace MxGateway.Client;
-
-/// <summary>
-/// Exposes the protocol versions compiled into this client package.
-/// </summary>
-public static class MxGatewayClientContractInfo
-{
-    /// <summary>
-    /// Gets the gateway gRPC protocol version compiled into this client package.
-    /// A client and gateway are wire-compatible only when this value matches the
-    /// gateway's advertised gateway protocol version.
-    /// </summary>
-    public const uint GatewayProtocolVersion =
-        GatewayContractInfo.GatewayProtocolVersion;
-
-    /// <summary>
-    /// Gets the worker frame protocol version compiled into this client package.
-    /// Exposed for diagnostics so callers can report the worker protocol the
-    /// shared contracts were generated against.
-    /// </summary>
-    public const uint WorkerProtocolVersion =
-        GatewayContractInfo.WorkerProtocolVersion;
-}
@@ -1,3 +0,0 @@
-using System.Runtime.CompilerServices;
-
-[assembly: InternalsVisibleTo("MxGateway.Client.Tests")]
@@ -1,55 +0,0 @@
-using Grpc.Core;
-
-namespace MxGateway.Client;
-
-/// <summary>
-/// Maps low-level <see cref="RpcException"/>s raised by the gRPC stack to the client's
-/// native exception hierarchy. Shared by every gateway and Galaxy Repository transport
-/// so the gRPC-to-native translation has exactly one implementation.
-/// </summary>
-internal static class RpcExceptionMapper
-{
-    /// <summary>
-    /// Translates a <see cref="RpcException"/> into the most specific native exception type.
-    /// </summary>
-    /// <param name="exception">The gRPC exception to translate.</param>
-    /// <param name="cancellationToken">
-    /// The cancellation token of the originating call; used to distinguish a caller-driven
-    /// cancellation from a server-side <see cref="StatusCode.Cancelled"/> status.
-    /// </param>
-    /// <returns>
-    /// An <see cref="OperationCanceledException"/> when the call was cancelled, a typed
-    /// authentication/authorization exception for auth statuses, or an
-    /// <see cref="MxGatewayException"/> carrying the originating gRPC <see cref="StatusCode"/>.
-    /// </returns>
-    public static Exception Map(
-        RpcException exception,
-        CancellationToken cancellationToken)
-    {
-        ArgumentNullException.ThrowIfNull(exception);
-
-        if (cancellationToken.IsCancellationRequested || exception.StatusCode == StatusCode.Cancelled)
-        {
-            return new OperationCanceledException(
-                exception.Status.Detail,
-                exception,
-                cancellationToken);
-        }
-
-        return exception.StatusCode switch
-        {
-            StatusCode.Unauthenticated => new MxGatewayAuthenticationException(
-                exception.Status.Detail,
-                statusCode: exception.StatusCode,
-                innerException: exception),
-            StatusCode.PermissionDenied => new MxGatewayAuthorizationException(
-                exception.Status.Detail,
-                statusCode: exception.StatusCode,
-                innerException: exception),
-            _ => new MxGatewayException(
-                exception.Status.Detail,
-                exception.StatusCode,
-                exception),
-        };
-    }
-}
@@ -7,11 +7,11 @@ CLI, and unit tests.

 | Project | Purpose |
 |---------|---------|
-| `MxGateway.Client` | .NET 10 library entry point, raw gRPC calls, and session helpers. |
-| `MxGateway.Client.Cli` | Test CLI for smoke and diagnostic commands. |
-| `MxGateway.Client.Tests` | Unit tests for client options, generated contract wiring, auth metadata, session helpers, cancellation, and event streaming. |
+| `ZB.MOM.WW.MxGateway.Client` | .NET 10 library entry point, raw gRPC calls, and session helpers. |
+| `ZB.MOM.WW.MxGateway.Client.Cli` | Test CLI for smoke and diagnostic commands. |
+| `ZB.MOM.WW.MxGateway.Client.Tests` | Unit tests for client options, generated contract wiring, auth metadata, session helpers, cancellation, and event streaming. |

-The projects reference `src/MxGateway.Contracts/MxGateway.Contracts.csproj` so
+The projects reference `src/ZB.MOM.WW.MxGateway.Contracts/ZB.MOM.WW.MxGateway.Contracts.csproj` so
 the client compiles against the same generated protobuf and gRPC types as the
 gateway. `clients/dotnet/generated` remains reserved for generator output if a
 future client build switches to client-local `Grpc.Tools` generation.
@@ -19,8 +19,8 @@ future client build switches to client-local `Grpc.Tools` generation.
 ## Build And Test

 ```powershell
-dotnet build clients/dotnet/MxGateway.Client.sln
-dotnet test clients/dotnet/MxGateway.Client.sln --no-build
+dotnet build clients/dotnet/ZB.MOM.WW.MxGateway.Client.slnx
+dotnet test clients/dotnet/ZB.MOM.WW.MxGateway.Client.slnx --no-build
 ```

 ## Packaging
@@ -29,8 +29,8 @@ Create local library and CLI artifacts from the repository root:

 ```powershell
 $dotnetPackageOutput = Join-Path (Get-Location) 'artifacts/clients/dotnet'
-dotnet pack clients/dotnet/MxGateway.Client/MxGateway.Client.csproj -c Release -p:PackageOutputPath="$dotnetPackageOutput"
-dotnet publish clients/dotnet/MxGateway.Client.Cli/MxGateway.Client.Cli.csproj -c Release -o artifacts/clients/dotnet/mxgw-dotnet
+dotnet pack clients/dotnet/ZB.MOM.WW.MxGateway.Client/ZB.MOM.WW.MxGateway.Client.csproj -c Release -p:PackageOutputPath="$dotnetPackageOutput"
+dotnet publish clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli/ZB.MOM.WW.MxGateway.Client.Cli.csproj -c Release -o artifacts/clients/dotnet/mxgw-dotnet
 ```

 The library package references the shared contracts project at build time. The
@@ -39,11 +39,11 @@ published CLI runs from `artifacts/clients/dotnet/mxgw-dotnet`.
 ## Regenerating Protobuf Bindings

 The .NET client uses the generated C# types from
-`src/MxGateway.Contracts/Generated`. Regenerate those files through the
+`src/ZB.MOM.WW.MxGateway.Contracts/Generated`. Regenerate those files through the
 contracts project:

 ```powershell
-dotnet build src/MxGateway.Contracts/MxGateway.Contracts.csproj
+dotnet build src/ZB.MOM.WW.MxGateway.Contracts/ZB.MOM.WW.MxGateway.Contracts.csproj
 ```

 ## Client Usage
@@ -84,47 +84,14 @@ messages. `MxGatewaySession.OpenSessionReply` keeps the raw session-open reply
 available, and command helpers have `*RawAsync` variants when callers need the
 complete `MxCommandReply`.

-### Bulk Commands
-
-The session exposes bulk variants for every command family that has one
-upstream — they all carry a list of entries in one gRPC round-trip, the worker
-runs the per-item MXAccess calls sequentially on its STA, and the reply
-returns one result per requested entry. Per-entry failures populate
-`WasSuccessful = false` with the underlying HRESULT and never throw; only
-protocol-level failures throw via `EnsureProtocolSuccess`.
-
-```csharp
-// Subscribe + Unsubscribe to a batch of tags in one round-trip
-IReadOnlyList<SubscribeResult> subResults = await session.SubscribeBulkAsync(
-    serverHandle,
-    new[] { "Area001.Pump001.Speed", "Area001.Pump001.RunHours" });
-int[] itemHandles = subResults.Where(r => r.WasSuccessful).Select(r => r.ItemHandle).ToArray();
-await session.UnsubscribeBulkAsync(serverHandle, itemHandles);
-
-// Bulk Write — sequential MXAccess Write per entry.
-IReadOnlyList<BulkWriteResult> writeResults = await session.WriteBulkAsync(
-    serverHandle,
-    new[]
-    {
-        new WriteBulkEntry { ItemHandle = h1, UserId = 0, Value = 1.0.ToMxValue() },
-        new WriteBulkEntry { ItemHandle = h2, UserId = 0, Value = 2.0.ToMxValue() },
-    });
-foreach (BulkWriteResult r in writeResults.Where(r => !r.WasSuccessful))
-{
-    Console.Error.WriteLine($"item {r.ItemHandle}: {r.ErrorMessage}");
-}
-
-// Bulk Read — returns the cached OnDataChange value when the tag is already
-// advised (was_cached = true) or takes a one-shot snapshot otherwise.
-IReadOnlyList<BulkReadResult> readResults = await session.ReadBulkAsync(
-    serverHandle,
-    new[] { "Area001.Pump001.Speed", "Area001.Pump002.Speed" },
-    timeout: TimeSpan.FromMilliseconds(750));
-```
-
-`Write2BulkAsync`, `WriteSecuredBulkAsync`, and `WriteSecured2BulkAsync` follow
-the same shape; the secured variants additionally carry `CurrentUserId` and
-`VerifierUserId` per entry and require `invoke:secure` scope.
+For alarms, the client exposes `QueryActiveAlarmsAsync` (one-shot snapshot of
+the active alarms the gateway's central monitor currently holds),
+`StreamAlarmsAsync` (server-streaming feed of alarm-state-change messages
+keyed by the same monitor), and `AcknowledgeAlarmAsync` (ack by alarm
+reference, optional comment, ack target). All three accept a cancellation
+token and pass through the `MxGateway:Alarms` configuration on the
+server — when alarms are disabled, the gateway returns an empty list / empty
+stream rather than failing.

 `MxGatewaySession.CloseAsync` is explicit and idempotent. Repeated calls return
 the first `CloseSessionReply` instead of sending another close request.
@@ -154,38 +121,28 @@ can keep the full `MxCommandReply`, HRESULT, and status array when MXAccess
 itself rejects a command. `MxAccessException.Reply` contains the raw generated
 reply.

-When a gRPC call itself fails, the transport maps the underlying
-`RpcException` to a native exception: `Unauthenticated` becomes
-`MxGatewayAuthenticationException`, `PermissionDenied` becomes
-`MxGatewayAuthorizationException`, a cancelled call becomes
-`OperationCanceledException`, and every other status becomes a base
-`MxGatewayException`. `MxGatewayException.StatusCode` carries the originating
-gRPC `Grpc.Core.StatusCode` (non-null whenever the failure came from a gRPC
-status), so callers can distinguish a transient outage (`Unavailable`) from a
-permanent error (`InvalidArgument`, `NotFound`) without downcasting
-`InnerException`.
-
 ## CLI Usage

 The test CLI supports deterministic JSON output for automation:

 ```powershell
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- version --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- open-session --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- register --session-id <id> --client-name mxgw-dotnet-cli --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- add-item --session-id <id> --server-handle 1 --item Area001.Pump001.Speed --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- advise --session-id <id> --server-handle 1 --item-handle 1 --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- write --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- write2 --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --timestamp 2026-01-01T00:00:00Z --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- stream-events --session-id <id> --max-events 1 --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- smoke --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --item Area001.Pump001.Speed --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- version --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- open-session --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- register --session-id <id> --client-name mxgw-dotnet-cli --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- add-item --session-id <id> --server-handle 1 --item Area001.Pump001.Speed --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- advise --session-id <id> --server-handle 1 --item-handle 1 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- write --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- write2 --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --timestamp 2026-01-01T00:00:00Z --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- stream-events --session-id <id> --max-events 1 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- stream-alarms --filter-prefix Area001 --max-events 1 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- acknowledge-alarm --reference "\\Galaxy\Area001.Pump001.PumpFault" --comment "ack from cli" --operator operator1 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- smoke --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --item Area001.Pump001.Speed --json
 ```

 `smoke` opens a session, registers a client, adds one item, advises it,
 optionally writes a value when `--type` and `--value` are supplied, reads a
 bounded event stream, and closes the session in a `finally` block. CLI error
-output redacts the effective API key, whether it was supplied through
-`--api-key` or resolved from the `--api-key-env` environment variable.
+output redacts API keys supplied through `--api-key`.

 ## Galaxy Repository Browse

@@ -234,11 +191,59 @@ IReadOnlyList<GalaxyObject> pumps = await repository.DiscoverHierarchyAsync(
 The CLI exposes the same operations:

 ```powershell
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-test-connection --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-last-deploy --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-discover --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-test-connection --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-last-deploy --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-discover --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
 ```

+### Browsing lazily
+
+For UI trees or OPC UA bridges, use `BrowseChildrenAsync` to walk one level at a
+time instead of paging the full hierarchy. Pass an empty request for root objects;
+subsequent calls supply `ParentGobjectId`, `ParentTagName`, or
+`ParentContainedPath`. Each child's `ChildHasChildren[i]` tells you whether to
+draw an expand triangle. Filter fields match `DiscoverHierarchy`. See
+[Galaxy Repository](../../docs/GalaxyRepository.md#browsechildren) for full
+request and filter semantics.
+
+```csharp
+BrowseChildrenReply roots = await repository.BrowseChildrenAsync(
+    new BrowseChildrenRequest());
+
+for (int i = 0; i < roots.Children.Count; i++)
+{
+    GalaxyObject child = roots.Children[i];
+    bool hasChildren = roots.ChildHasChildren[i];
+    Console.WriteLine($"{child.TagName} expand={hasChildren}");
+}
+```
+
+#### High-level walker
+
+For UI trees, the client provides a `LazyBrowseNode` walker that handles
+sibling pagination and the `child_has_children` hint for you:
+
+```csharp
+await using GalaxyRepositoryClient repository = GalaxyRepositoryClient.Create(
+    new MxGatewayClientOptions { Endpoint = new Uri("http://localhost:5000"), ApiKey = apiKey });
+IReadOnlyList<LazyBrowseNode> roots = await repository.BrowseAsync();
+foreach (LazyBrowseNode root in roots)
+{
+    if (root.HasChildrenHint)
+    {
+        await root.ExpandAsync();
+    }
+    foreach (LazyBrowseNode child in root.Children)
+    {
+        Console.WriteLine($"{child.Object.TagName} ({(child.HasChildrenHint ? "has children" : "leaf")})");
+    }
+}
+```
+
+`ExpandAsync` is idempotent — calling it twice fires only one RPC,
+and is safe under concurrent callers. To refresh after a Galaxy redeploy, call
+`BrowseAsync` again from the root.
+
 ### Watching deploy events

 `WatchDeployEventsAsync` opens the `WatchDeployEvents` server-streaming RPC. The
@@ -271,17 +276,28 @@ await foreach (DeployEvent evt in repository.WatchDeployEventsAsync(
 The CLI counterpart streams events until Ctrl+C (or `--max-events`):

 ```powershell
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --last-seen-deploy-time 2026-04-28T14:30:00Z --json
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --max-events 5 --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --last-seen-deploy-time 2026-04-28T14:30:00Z --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --max-events 5 --json
 ```

 Use TLS options for a secured gateway:

 ```powershell
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- smoke --endpoint https://mxgateway.example.local:5001 --tls --ca-file C:\certs\mxgateway-ca.pem --server-name mxgateway.example.local --api-key-env MXGATEWAY_API_KEY --item Area001.Pump001.Speed --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- smoke --endpoint https://ZB.MOM.WW.MxGateway.example.local:5001 --tls --ca-file C:\certs\mxgateway-ca.pem --server-name ZB.MOM.WW.MxGateway.example.local --api-key-env MXGATEWAY_API_KEY --item Area001.Pump001.Speed --json
 ```

+### TLS trust
+
+The gateway can auto-generate its own self-signed certificate (it has no PKI), so
+the client is **lenient by default**: a TLS connection (`UseTls` / `--tls`) with
+no pinned CA accepts whatever certificate the gateway presents. To verify
+instead, pin a CA with `CaCertificatePath` / `--ca-file` (this path also enforces
+the certificate hostname/SAN match), or set `RequireCertificateValidation` to
+force OS/system-trust verification without pinning. Use `ServerNameOverride` /
+`--server-name` when the dialed host differs from the certificate SAN. See
+[Gateway Configuration](../../docs/GatewayConfiguration.md#automatic-self-signed-certificate).
+
 ## Integration Checks

 Run live checks only when a gateway and MXAccess-backed worker are available:
@@ -291,9 +307,32 @@ $env:MXGATEWAY_INTEGRATION = '1'
 $env:MXGATEWAY_ENDPOINT = 'http://localhost:5000'
 $env:MXGATEWAY_API_KEY = '<gateway-api-key>'
 $env:MXGATEWAY_TEST_ITEM = 'Area001.Pump001.Speed'
-dotnet run --project clients/dotnet/MxGateway.Client.Cli -- smoke --endpoint $env:MXGATEWAY_ENDPOINT --api-key-env MXGATEWAY_API_KEY --item $env:MXGATEWAY_TEST_ITEM --json
+dotnet run --project clients/dotnet/ZB.MOM.WW.MxGateway.Client.Cli -- smoke --endpoint $env:MXGATEWAY_ENDPOINT --api-key-env MXGATEWAY_API_KEY --item $env:MXGATEWAY_TEST_ITEM --json
 ```

+## Installing as a NuGet Package
+
+The client publishes to the internal Gitea NuGet feed at
+`https://gitea.dohertylan.com/api/packages/dohertj2/nuget/index.json`.
+
+Add the feed once:
+
+````bash
+dotnet nuget add source https://gitea.dohertylan.com/api/packages/dohertj2/nuget/index.json \
+    --name dohertj2-gitea \
+    --username <gitea-username> \
+    --password <gitea-token-or-password> \
+    --store-password-in-clear-text
+````
+
+Then add the package to your project:
+
+````bash
+dotnet add package ZB.MOM.WW.MxGateway.Client --version 0.1.0
+````
+
+The `ZB.MOM.WW.MxGateway.Contracts` package is pulled in transitively.
+
 ## Related Documentation

 - [Client Packaging](../../docs/ClientPackaging.md)
@@ -1,6 +1,6 @@
 using System.Globalization;

-namespace MxGateway.Client.Cli;
+namespace ZB.MOM.WW.MxGateway.Client.Cli;

 /// <summary>Parses command-line arguments into flags and named values.</summary>
 internal sealed class CliArguments
@@ -44,6 +44,7 @@ internal sealed class CliArguments

    /// <summary>Returns whether the named flag was present in the arguments.</summary>
    /// <param name="name">The flag name (without '--' prefix).</param>
+    /// <returns>True if the flag was present; otherwise false.</returns>
    public bool HasFlag(string name)
    {
        return _flags.Contains(name);
@@ -51,6 +52,7 @@ internal sealed class CliArguments

    /// <summary>Returns the value for a named argument, or <c>null</c> if absent.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
+    /// <returns>The argument value, or null if the argument was not provided.</returns>
    public string? GetOptional(string name)
    {
        return _values.TryGetValue(name, out string? value)
@@ -60,6 +62,7 @@ internal sealed class CliArguments

    /// <summary>Returns the value for a required named argument, or throws if absent.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
+    /// <returns>The argument value.</returns>
    public string GetRequired(string name)
    {
        string? value = GetOptional(name);
@@ -74,6 +77,7 @@ internal sealed class CliArguments
    /// <summary>Parses and returns an int32 argument, or the default value if absent.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
    /// <param name="defaultValue">The default value if the argument is absent; if <c>null</c>, the argument is required.</param>
+    /// <returns>The parsed int32 value, or the default if absent.</returns>
    public int GetInt32(string name, int? defaultValue = null)
    {
        string? value = GetOptional(name);
@@ -93,6 +97,7 @@ internal sealed class CliArguments
    /// <summary>Parses and returns a uint32 argument, or the default value if absent.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
    /// <param name="defaultValue">The default value if the argument is absent.</param>
+    /// <returns>The parsed uint32 value, or the default if absent.</returns>
    public uint GetUInt32(string name, uint defaultValue)
    {
        string? value = GetOptional(name);
@@ -104,6 +109,7 @@ internal sealed class CliArguments
    /// <summary>Parses and returns a uint64 argument, or the default value if absent.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
    /// <param name="defaultValue">The default value if the argument is absent.</param>
+    /// <returns>The parsed uint64 value, or the default if absent.</returns>
    public ulong GetUInt64(string name, ulong defaultValue)
    {
        string? value = GetOptional(name);
@@ -115,6 +121,7 @@ internal sealed class CliArguments
    /// <summary>Parses and returns a TimeSpan argument, or the default value if absent. Supports "ms", "s", and standard TimeSpan format.</summary>
    /// <param name="name">The argument name (without '--' prefix).</param>
    /// <param name="defaultValue">The default value if the argument is absent.</param>
+    /// <returns>The parsed TimeSpan value, or the default if absent.</returns>
    public TimeSpan GetDuration(string name, TimeSpan defaultValue)
    {
        string? value = GetOptional(name);
@@ -1,14 +1,8 @@
-using MxGateway.Contracts.Proto;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Cli;
+namespace ZB.MOM.WW.MxGateway.Client.Cli;

-/// <summary>
-/// Minimal transport surface the CLI talks to. Exposes only the gateway and
-/// Galaxy Repository RPCs the CLI needs so tests can substitute an in-process
-/// fake without standing up a real gRPC channel. The production binding is a
-/// thin adapter over <see cref="MxGatewayClient"/> and <see cref="GalaxyRepositoryClient"/>.
-/// </summary>
 public interface IMxGatewayCliClient : IAsyncDisposable
 {
    /// <summary>
@@ -1,8 +1,8 @@
-using MxGateway.Client;
-using MxGateway.Contracts.Proto;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Cli;
+namespace ZB.MOM.WW.MxGateway.Client.Cli;

 internal sealed class MxGatewayCliClientAdapter : IMxGatewayCliClient
 {
@@ -100,7 +100,8 @@ internal sealed class MxGatewayCliClientAdapter : IMxGatewayCliClient
        return _galaxyClient.Value.WatchDeployEventsRawAsync(request, cancellationToken);
    }

-    /// <inheritdoc />
+    /// <summary>Disposes the galaxy client (if created) and the underlying gateway client.</summary>
+    /// <returns>A value task that completes when both clients are disposed.</returns>
    public async ValueTask DisposeAsync()
    {
        if (_galaxyClient.IsValueCreated)
@@ -1,4 +1,4 @@
-namespace MxGateway.Client.Cli;
+namespace ZB.MOM.WW.MxGateway.Client.Cli;

 /// <summary>Utility to redact API keys from error messages for safe output.</summary>
 internal static class MxGatewayCliSecretRedactor
@@ -6,6 +6,7 @@ internal static class MxGatewayCliSecretRedactor
    /// <summary>Replaces occurrences of the API key in the value with a redacted placeholder.</summary>
    /// <param name="value">The message text to redact.</param>
    /// <param name="apiKey">The API key to remove; no redaction if null or empty.</param>
+    /// <returns>The message text with any API key occurrence replaced by <c>[redacted]</c>.</returns>
    public static string Redact(string value, string? apiKey)
    {
        if (string.IsNullOrEmpty(value) || string.IsNullOrEmpty(apiKey))
@@ -1,11 +1,11 @@
 using System.Globalization;
 using System.Text.Json;
 using Google.Protobuf;
-using MxGateway.Client;
-using MxGateway.Contracts.Proto;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Cli;
+namespace ZB.MOM.WW.MxGateway.Client.Cli;

 /// <summary>Command-line interface for the MXAccess Gateway client, supporting session and command operations.</summary>
 public static class MxGatewayClientCli
@@ -16,10 +16,13 @@ public static class MxGatewayClientCli

    private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web);

+    private const string BatchEndOfRecord = "__MXGW_BATCH_EOR__";
+
    /// <summary>Runs the CLI synchronously with the given arguments, writing output and errors.</summary>
    /// <param name="args">Command-line arguments (command name followed by options).</param>
    /// <param name="standardOutput">TextWriter for command output.</param>
    /// <param name="standardError">TextWriter for error messages.</param>
+    /// <returns>The process exit code (0 for success, 1 for error).</returns>
    public static int Run(
        string[] args,
        TextWriter standardOutput,
@@ -36,6 +39,7 @@ public static class MxGatewayClientCli
    /// <param name="standardError">TextWriter for error messages.</param>
    /// <param name="clientFactory">Optional factory to create the gateway client; defaults to MxGatewayClient.Create.</param>
    /// <param name="standardInput">Optional TextReader for batch-mode stdin; defaults to <see cref="Console.In"/>.</param>
+    /// <returns>A task that resolves to the process exit code (0 for success, 1 for error).</returns>
    public static Task<int> RunAsync(
        string[] args,
        TextWriter standardOutput,
@@ -55,8 +59,6 @@ public static class MxGatewayClientCli
            standardInput ?? Console.In);
    }

-    private const string BatchEndOfRecord = "__MXGW_BATCH_EOR__";
-
    private static async Task<int> RunCoreAsync(
        string[] args,
        TextWriter standardOutput,
@@ -126,8 +128,6 @@ public static class MxGatewayClientCli
                    .ConfigureAwait(false),
                "bench-read-bulk" => await BenchReadBulkAsync(arguments, client, standardOutput, cancellation.Token)
                    .ConfigureAwait(false),
-                "bench-stream-events" => await BenchStreamEventsAsync(arguments, client, standardOutput, cancellation.Token)
-                    .ConfigureAwait(false),
                "stream-events" => await StreamEventsAsync(arguments, client, standardOutput, cancellation.Token)
                    .ConfigureAwait(false),
                "stream-alarms" => await StreamAlarmsAsync(arguments, client, standardOutput, cancellation.Token)
@@ -153,10 +153,7 @@ public static class MxGatewayClientCli
        }
        catch (Exception exception) when (exception is not OperationCanceledException)
        {
-            // Redact the effective API key — whether it came from --api-key or from
-            // the (documented default) --api-key-env environment variable — so a
-            // transport error message that echoes the bearer token is never printed.
-            string? apiKey = TryResolveApiKey(arguments);
+            string? apiKey = arguments.GetOptional("api-key");
            string message = MxGatewayCliSecretRedactor.Redact(exception.Message, apiKey);

            if (forceJsonErrors || arguments.HasFlag("json"))
@@ -174,88 +171,6 @@ public static class MxGatewayClientCli
        }
    }

-    private static IMxGatewayCliClient CreateDefaultClient(MxGatewayClientOptions options)
-    {
-        return new MxGatewayCliClientAdapter(MxGatewayClient.Create(options));
-    }
-
-    private static MxGatewayClientOptions CreateOptions(CliArguments arguments)
-    {
-        string endpoint = arguments.GetOptional("endpoint")
-            ?? Environment.GetEnvironmentVariable("MXGATEWAY_ENDPOINT")
-            ?? "http://localhost:5000";
-
-        string apiKey = ResolveApiKey(arguments);
-
-        return new MxGatewayClientOptions
-        {
-            Endpoint = new Uri(endpoint, UriKind.Absolute),
-            ApiKey = apiKey,
-            UseTls = arguments.HasFlag("tls")
-                || endpoint.StartsWith("https://", StringComparison.OrdinalIgnoreCase),
-            DefaultCallTimeout = arguments.GetDuration("timeout", TimeSpan.FromSeconds(30)),
-            ConnectTimeout = arguments.GetDuration("connect-timeout", TimeSpan.FromSeconds(10)),
-            CaCertificatePath = arguments.GetOptional("ca-file"),
-            ServerNameOverride = arguments.GetOptional("server-name"),
-        };
-    }
-
-    private static string ResolveApiKey(CliArguments arguments)
-    {
-        string? apiKey = TryResolveApiKey(arguments);
-        if (!string.IsNullOrWhiteSpace(apiKey))
-        {
-            return apiKey;
-        }
-
-        string apiKeyEnvironmentName = arguments.GetOptional("api-key-env")
-            ?? "MXGATEWAY_API_KEY";
-
-        throw new ArgumentException(
-            $"Gateway API key is required. Pass --api-key or set {apiKeyEnvironmentName}.");
-    }
-
-    /// <summary>
-    /// Resolves the effective API key from <c>--api-key</c> or, failing that, the
-    /// environment variable named by <c>--api-key-env</c> (default
-    /// <c>MXGATEWAY_API_KEY</c>). Returns <see langword="null"/> when no key is
-    /// configured; used for redaction where a missing key must not throw.
-    /// </summary>
-    private static string? TryResolveApiKey(CliArguments arguments)
-    {
-        string? apiKey = arguments.GetOptional("api-key");
-        if (!string.IsNullOrWhiteSpace(apiKey))
-        {
-            return apiKey;
-        }
-
-        string apiKeyEnvironmentName = arguments.GetOptional("api-key-env")
-            ?? "MXGATEWAY_API_KEY";
-
-        return Environment.GetEnvironmentVariable(apiKeyEnvironmentName);
-    }
-
-    private static CancellationTokenSource CreateCancellation(CliArguments arguments, string command)
-    {
-        var cancellation = new CancellationTokenSource();
-        // Long-running streaming / bench commands run until they finish (or Ctrl+C)
-        // by default; a caller-supplied --timeout still applies if present. The
-        // bench commands default to --duration-seconds=30 --warmup-seconds=3 plus
-        // a per-session stagger, which already exceeds the default 30 s wall-clock
-        // budget, so applying that budget would cancel them mid-window and emit a
-        // zero-throughput JSON payload (see Client.Dotnet-015).
-        bool isLongRunning = command is "galaxy-watch" or "bench-read-bulk" or "bench-stream-events";
-        string? rawTimeout = arguments.GetOptional("timeout");
-        if (isLongRunning && string.IsNullOrWhiteSpace(rawTimeout))
-        {
-            return cancellation;
-        }
-
-        TimeSpan timeout = arguments.GetDuration("timeout", TimeSpan.FromSeconds(30));
-        cancellation.CancelAfter(timeout);
-        return cancellation;
-    }
-
    /// <summary>
    ///     Runs the CLI in batch mode: reads one command line at a time from
    ///     <paramref name="standardInput"/>, dispatches it through the normal
@@ -303,9 +218,13 @@ public static class MxGatewayClientCli
                        forceJsonErrors: true)
                    .ConfigureAwait(false);
            }
-            catch (Exception exception) when (exception is not OperationCanceledException)
+            catch (Exception exception)
            {
                // Unexpected exception that escaped RunCoreAsync (shouldn't happen, but be safe).
+                // OperationCanceledException from long-running streaming commands
+                // (e.g. galaxy-watch hit by --timeout) is caught here too — the
+                // batch process must continue with the next command rather than
+                // unwinding.
                commandError.WriteLine(JsonSerializer.Serialize(
                    new { error = exception.Message, type = exception.GetType().Name },
                    JsonOptions));
@@ -332,6 +251,70 @@ public static class MxGatewayClientCli
        }
    }

+    private static IMxGatewayCliClient CreateDefaultClient(MxGatewayClientOptions options)
+    {
+        return new MxGatewayCliClientAdapter(MxGatewayClient.Create(options));
+    }
+
+    private static MxGatewayClientOptions CreateOptions(CliArguments arguments)
+    {
+        string endpoint = arguments.GetOptional("endpoint")
+            ?? Environment.GetEnvironmentVariable("MXGATEWAY_ENDPOINT")
+            ?? "http://localhost:5000";
+
+        string apiKey = ResolveApiKey(arguments);
+
+        return new MxGatewayClientOptions
+        {
+            Endpoint = new Uri(endpoint, UriKind.Absolute),
+            ApiKey = apiKey,
+            UseTls = arguments.HasFlag("tls")
+                || endpoint.StartsWith("https://", StringComparison.OrdinalIgnoreCase),
+            DefaultCallTimeout = arguments.GetDuration("timeout", TimeSpan.FromSeconds(30)),
+            ConnectTimeout = arguments.GetDuration("connect-timeout", TimeSpan.FromSeconds(10)),
+            CaCertificatePath = arguments.GetOptional("ca-file"),
+            ServerNameOverride = arguments.GetOptional("server-name"),
+        };
+    }
+
+    private static string ResolveApiKey(CliArguments arguments)
+    {
+        string? apiKey = arguments.GetOptional("api-key");
+        if (!string.IsNullOrWhiteSpace(apiKey))
+        {
+            return apiKey;
+        }
+
+        string apiKeyEnvironmentName = arguments.GetOptional("api-key-env")
+            ?? "MXGATEWAY_API_KEY";
+
+        apiKey = Environment.GetEnvironmentVariable(apiKeyEnvironmentName);
+        if (!string.IsNullOrWhiteSpace(apiKey))
+        {
+            return apiKey;
+        }
+
+        throw new ArgumentException(
+            $"Gateway API key is required. Pass --api-key or set {apiKeyEnvironmentName}.");
+    }
+
+    private static CancellationTokenSource CreateCancellation(CliArguments arguments, string command)
+    {
+        var cancellation = new CancellationTokenSource();
+        // Long-running streaming commands run until Ctrl+C / cancellation by default;
+        // a caller-supplied --timeout still applies if present.
+        bool isLongRunning = command is "galaxy-watch";
+        string? rawTimeout = arguments.GetOptional("timeout");
+        if (isLongRunning && string.IsNullOrWhiteSpace(rawTimeout))
+        {
+            return cancellation;
+        }
+
+        TimeSpan timeout = arguments.GetDuration("timeout", TimeSpan.FromSeconds(30));
+        cancellation.CancelAfter(timeout);
+        return cancellation;
+    }
+
    private static Task<int> OpenSessionAsync(
        CliArguments arguments,
        IMxGatewayCliClient client,
@@ -506,7 +489,7 @@ public static class MxGatewayClientCli
        ReadBulkCommand command = new()
        {
            ServerHandle = arguments.GetInt32("server-handle"),
-            TimeoutMs = (uint)arguments.GetInt32("timeout-ms", 0),
+            TimeoutMs = ParseTimeoutMs(arguments, defaultValue: 0),
        };
        command.TagAddresses.Add(ParseStringList(arguments.GetRequired("items")));

@@ -682,6 +665,78 @@ public static class MxGatewayClientCli
            cancellationToken);
    }

+    /// <summary>
+    ///     Parses the bulk-write CLI's <c>--values</c> list. All entries share
+    ///     the single <c>--type</c> argument; the comma-separated values are
+    ///     each parsed via <see cref="ParseValue(string, string)"/> on a per-entry basis.
+    ///     This keeps the CLI simple for e2e use (one type, N values) — callers
+    ///     that need heterogeneous types per entry should drive the library
+    ///     directly.
+    /// </summary>
+    private static IReadOnlyList<MxValue> ParseValuesList(CliArguments arguments)
+    {
+        string type = arguments.GetRequired("type");
+        string[] values = ParseStringList(arguments.GetRequired("values")).ToArray();
+        MxValue[] result = new MxValue[values.Length];
+        for (int i = 0; i < values.Length; i++)
+        {
+            result[i] = ParseValue(type, values[i]);
+        }
+        return result;
+    }
+
+    private static void EnsureSameLength(int handles, int values)
+    {
+        if (handles != values)
+        {
+            throw new ArgumentException(
+                $"Bulk write requires the same number of --item-handles ({handles}) and --values ({values}).");
+        }
+    }
+
+    /// <summary>
+    ///     Parses the optional <c>--timeout-ms</c> argument as a non-negative
+    ///     unsigned millisecond count. Mirrors the SDK-side <c>(uint)Math.Min</c>
+    ///     guard on <c>MxGatewaySession.ReadBulkAsync</c>: a negative value
+    ///     (e.g. <c>-1</c>, an easy copy-paste mistake for "unbounded") is
+    ///     rejected loudly rather than silently wrapped to <c>~49.7 days</c>,
+    ///     which would park one worker thread per pending tag for hours.
+    ///     Resolves Client.Dotnet-021.
+    /// </summary>
+    private static uint ParseTimeoutMs(CliArguments arguments, int defaultValue)
+    {
+        int raw = arguments.GetInt32("timeout-ms", defaultValue);
+        if (raw < 0)
+        {
+            throw new ArgumentException(
+                "--timeout-ms must be a non-negative integer (use 0 for the gateway default).");
+        }
+
+        return (uint)raw;
+    }
+
+    /// <summary>
+    ///     Extracts the <c>ServerHandle</c> from a Register reply, throwing a
+    ///     descriptive <see cref="MxGatewayException"/> when the typed
+    ///     <c>Register</c> payload is absent on an otherwise-successful reply.
+    ///     The typed sub-message is the contract for the Register command, so
+    ///     its absence must not silently fall through to
+    ///     <c>ReturnValue.Int32Value</c> (which would be <c>0</c> for an empty
+    ///     reply, driving the rest of the bench against an invalid handle).
+    ///     Resolves Client.Dotnet-019.
+    /// </summary>
+    private static int RequireRegisterServerHandle(MxCommandReply reply, string sessionId)
+    {
+        if (reply.Register is null)
+        {
+            throw new MxGatewayException(
+                $"Gateway reply for Register on session '{sessionId}' (correlation '{reply.CorrelationId}') "
+                + "succeeded but is missing the typed 'register' payload required to read ServerHandle.");
+        }
+
+        return reply.Register.ServerHandle;
+    }
+
    /// <summary>
    ///     Cross-language stress benchmark for ReadBulk. Opens its own session,
    ///     subscribes to N tags so the worker's MxAccessValueCache populates from
@@ -702,7 +757,7 @@ public static class MxGatewayClientCli
        int tagStart = arguments.GetInt32("tag-start", 1);
        string tagPrefix = arguments.GetOptional("tag-prefix") ?? "TestMachine_";
        string tagAttribute = arguments.GetOptional("tag-attribute") ?? "TestChangingInt";
-        uint timeoutMs = (uint)arguments.GetInt32("timeout-ms", 1500);
+        uint timeoutMs = ParseTimeoutMs(arguments, defaultValue: 1500);
        string clientName = arguments.GetOptional("client-name") ?? "mxgw-dotnet-bench";

        string[] tags = new string[bulkSize];
@@ -732,7 +787,7 @@ public static class MxGatewayClientCli
                    }),
                    cancellationToken)
                .ConfigureAwait(false);
-            int serverHandle = RequireRegisterServerHandle(registerReply);
+            int serverHandle = RequireRegisterServerHandle(registerReply, sessionId);

            SubscribeBulkCommand subscribe = new() { ServerHandle = serverHandle };
            subscribe.TagAddresses.Add(tags);
@@ -791,8 +846,13 @@ public static class MxGatewayClientCli
                        .ConfigureAwait(false);
                    sw.Stop();
                }
-                catch
+                catch (Exception ex) when (ex is not OperationCanceledException)
                {
+                    // Client.Dotnet-020: never swallow OperationCanceledException
+                    // here. A bare `catch` would let Ctrl+C / parent CTS /
+                    // wall-clock timeouts keep spinning until --duration-seconds
+                    // elapsed, burning CPU and skewing the p99/max latency numbers
+                    // with hundreds of immediate-OCE iterations.
                    sw.Stop();
                    failedCalls++;
                    latencyMillis.Add(sw.Elapsed.TotalMilliseconds);
@@ -886,295 +946,6 @@ public static class MxGatewayClientCli
        }
    }

-    /// <summary>
-    ///     Single-client event-rate stress benchmark. Opens its own session,
-    ///     subscribes to <c>--bulk-size</c> tags spanning the dev galaxy's
-    ///     TestMachine_NNN.* set, then drains the gateway's StreamEvents
-    ///     server-stream as fast as it can for <c>--duration-seconds</c>.
-    ///     Tracks events received per second, end-to-end latency from
-    ///     <c>event.worker_timestamp</c> to client receive time, and any
-    ///     worker faults emitted by the gateway over the same window.
-    ///     <para>
-    ///     The companion <c>--all-attributes</c> flag (default <c>true</c>)
-    ///     subscribes to all six TestMachine attributes per machine number
-    ///     so the bench can drive event volume past one-attribute-per-machine
-    ///     when the dev galaxy's TestChangingInt is the only churning tag.
-    ///     </para>
-    /// </summary>
-    private static async Task<int> BenchStreamEventsAsync(
-        CliArguments arguments,
-        IMxGatewayCliClient client,
-        TextWriter output,
-        CancellationToken cancellationToken)
-    {
-        int durationSeconds = arguments.GetInt32("duration-seconds", 30);
-        int warmupSeconds = arguments.GetInt32("warmup-seconds", 3);
-        int bulkSize = arguments.GetInt32("bulk-size", 60);
-        int tagStart = arguments.GetInt32("tag-start", 1);
-        int sessionCount = arguments.GetInt32("session-count", 1);
-        // Concurrent OpenSession calls all the way up the stack force the
-        // gateway to spawn N x86 workers simultaneously; that hits the
-        // 30-second worker startup timeout around 6-8 concurrent opens on
-        // a dev rig. The stagger spreads the opens out so per-session
-        // OpenSession+Register completes inside that budget before the
-        // next session starts spawning. The steady-state event window
-        // begins only once all sessions are open and subscribed.
-        int sessionStartStaggerMs = arguments.GetInt32("session-start-stagger-ms", sessionCount > 1 ? 750 : 0);
-        string tagPrefix = arguments.GetOptional("tag-prefix") ?? "TestMachine_";
-        bool allAttributes = !arguments.HasFlag("single-attribute");
-        string singleAttribute = arguments.GetOptional("tag-attribute") ?? "TestChangingInt";
-        string clientName = arguments.GetOptional("client-name") ?? "mxgw-dotnet-bench-events";
-
-        if (sessionCount < 1)
-        {
-            throw new ArgumentException("--session-count must be >= 1.");
-        }
-
-        // Build the tag set. With --all-attributes (default) we rotate through
-        // all six TestMachine attributes to drive more event volume from a
-        // smaller machine range; with --single-attribute we use the same
-        // attribute on contiguous machine numbers (the original bench-read-
-        // bulk shape).
-        string[] attributes = allAttributes
-            ? new[] { "TestChangingInt", "ProtectedValue", "TestBoolArray[]", "TestIntArray[]", "TestDateTimeArray[]", "TestStringArray[]" }
-            : new[] { singleAttribute };
-        List<string> tags = new(capacity: bulkSize);
-        for (int i = 0; i < bulkSize; i++)
-        {
-            int machineNumber = tagStart + (i / attributes.Length);
-            string attribute = attributes[i % attributes.Length];
-            tags.Add($"{tagPrefix}{machineNumber:D3}.{attribute}");
-        }
-
-        long warmupEvents = 0;
-        long steadyEvents = 0;
-        long steadyDataChangeEvents = 0;
-        List<double> endToEndLatencyMs = new(capacity: 262_144);
-        object latencyLock = new();
-        DateTime? firstSteadyEventUtc = null;
-        DateTime? lastSteadyEventUtc = null;
-        int totalSubscribeFailures = 0;
-        int totalSubscribedTagCount = 0;
-        int totalDrainedFaultCount = 0;
-        DateTime warmupStart = default;
-        DateTime warmupEnd = default;
-        DateTime steadyEnd = default;
-
-        // Phase 1: open + subscribe each session sequentially with a stagger,
-        // so worker spawn-up doesn't exceed the gateway's per-session startup
-        // timeout. Each session stashes its (sessionId, serverHandle, itemHandles)
-        // for phase 2.
-        var openedSessions = new List<(string SessionId, int ServerHandle, int[] ItemHandles, string ClientName)>(sessionCount);
-        for (int sessionIndex = 0; sessionIndex < sessionCount; sessionIndex++)
-        {
-            if (sessionIndex > 0 && sessionStartStaggerMs > 0)
-            {
-                await Task.Delay(sessionStartStaggerMs, cancellationToken).ConfigureAwait(false);
-            }
-
-            string thisClientName = sessionCount == 1
-                ? clientName
-                : $"{clientName}-{sessionIndex:D2}";
-            OpenSessionReply openReply = await client.OpenSessionAsync(
-                    new OpenSessionRequest { ClientSessionName = thisClientName, ClientCorrelationId = CreateCorrelationId() },
-                    cancellationToken)
-                .ConfigureAwait(false);
-            string sessionId = openReply.SessionId;
-
-            MxCommandReply registerReply = await InvokeAndEnsureAsync(
-                    client,
-                    CreateCommandRequest(sessionId, new MxCommand
-                    {
-                        Kind = MxCommandKind.Register,
-                        Register = new RegisterCommand { ClientName = thisClientName },
-                    }),
-                    cancellationToken)
-                .ConfigureAwait(false);
-            int serverHandle = RequireRegisterServerHandle(registerReply);
-
-            SubscribeBulkCommand subscribe = new() { ServerHandle = serverHandle };
-            subscribe.TagAddresses.Add(tags);
-            MxCommandReply subscribeReply = await InvokeAndEnsureAsync(
-                    client,
-                    CreateCommandRequest(sessionId, new MxCommand
-                    {
-                        Kind = MxCommandKind.SubscribeBulk,
-                        SubscribeBulk = subscribe,
-                    }),
-                    cancellationToken)
-                .ConfigureAwait(false);
-            SubscribeResult[] subscribeResults = subscribeReply.SubscribeBulk?.Results.ToArray() ?? [];
-            int[] itemHandles = subscribeResults.Where(r => r.WasSuccessful).Select(r => r.ItemHandle).ToArray();
-            totalSubscribedTagCount += itemHandles.Length;
-            totalSubscribeFailures += subscribeResults.Count(r => !r.WasSuccessful);
-            openedSessions.Add((sessionId, serverHandle, itemHandles, thisClientName));
-        }
-
-        // Phase 2: now every session is open + advised. Start the measurement
-        // window and run each session's StreamEvents reader in parallel.
-        warmupStart = DateTime.UtcNow;
-        warmupEnd = warmupStart + TimeSpan.FromSeconds(warmupSeconds);
-        steadyEnd = warmupEnd + TimeSpan.FromSeconds(durationSeconds);
-
-        async Task RunStreamAsync((string SessionId, int ServerHandle, int[] ItemHandles, string ClientName) ctx)
-        {
-            using CancellationTokenSource streamCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
-
-            Task streamTask = Task.Run(async () =>
-            {
-                StreamEventsRequest streamRequest = new() { SessionId = ctx.SessionId };
-                await foreach (MxEvent mxEvent in client.StreamEventsAsync(streamRequest, streamCts.Token)
-                    .ConfigureAwait(false))
-                {
-                    DateTime nowUtc = DateTime.UtcNow;
-                    if (nowUtc >= steadyEnd)
-                    {
-                        break;
-                    }
-
-                    if (nowUtc < warmupEnd)
-                    {
-                        Interlocked.Increment(ref warmupEvents);
-                        continue;
-                    }
-
-                    // Guarded by latencyLock so parallel sessions can't tear a 64-bit
-                    // DateTime? read or stomp an already-set firstSteadyEventUtc with
-                    // a later timestamp from a slower-to-start session. The lock is
-                    // already held by the latency append a few lines below, so the
-                    // extra cost is one uncontended lock acquisition per event.
-                    lock (latencyLock)
-                    {
-                        firstSteadyEventUtc ??= nowUtc;
-                        lastSteadyEventUtc = nowUtc;
-                    }
-                    Interlocked.Increment(ref steadyEvents);
-                    if (mxEvent.Family == MxEventFamily.OnDataChange)
-                    {
-                        Interlocked.Increment(ref steadyDataChangeEvents);
-                    }
-
-                    if (mxEvent.WorkerTimestamp is { } workerStamp)
-                    {
-                        double latency = (nowUtc - workerStamp.ToDateTime()).TotalMilliseconds;
-                        if (latency >= 0)
-                        {
-                            lock (latencyLock) { endToEndLatencyMs.Add(latency); }
-                        }
-                    }
-                }
-            }, streamCts.Token);
-
-            // The inner streamTask MUST be observed on every path — including when
-            // the outer cancellationToken cancels during the Task.Delay below — or
-            // its fault surfaces as a TaskScheduler.UnobservedTaskException after
-            // GC. Use try/finally so the cancel + await pair always runs (see
-            // Client.Dotnet-016). RpcException(Cancelled) never reaches here in
-            // production because GrpcMxGatewayClientTransport.StreamEventsAsync
-            // routes through RpcExceptionMapper.Map, which returns OCE for
-            // StatusCode.Cancelled.
-            try
-            {
-                await Task.Delay(steadyEnd - warmupStart, cancellationToken).ConfigureAwait(false);
-            }
-            finally
-            {
-                streamCts.Cancel();
-                try { await streamTask.ConfigureAwait(false); }
-                catch (OperationCanceledException) { }
-                catch (MxGatewayException) { }
-            }
-
-            try
-            {
-                MxCommandReply drainReply = await client.InvokeAsync(
-                        CreateCommandRequest(ctx.SessionId, new MxCommand
-                        {
-                            Kind = MxCommandKind.DrainEvents,
-                            DrainEvents = new DrainEventsCommand { MaxEvents = 16 },
-                        }),
-                        cancellationToken)
-                    .ConfigureAwait(false);
-                Interlocked.Add(ref totalDrainedFaultCount, drainReply.DrainEvents?.Events.Count ?? 0);
-            }
-            catch { /* fault probe is best-effort */ }
-
-            if (ctx.ItemHandles.Length > 0)
-            {
-                try
-                {
-                    UnsubscribeBulkCommand unsubscribe = new() { ServerHandle = ctx.ServerHandle };
-                    unsubscribe.ItemHandles.Add(ctx.ItemHandles);
-                    _ = await client.InvokeAsync(
-                            CreateCommandRequest(ctx.SessionId, new MxCommand
-                            {
-                                Kind = MxCommandKind.UnsubscribeBulk,
-                                UnsubscribeBulk = unsubscribe,
-                            }),
-                            cancellationToken)
-                        .ConfigureAwait(false);
-                }
-                catch { /* best-effort */ }
-            }
-
-            try
-            {
-                await client.CloseSessionAsync(
-                        new CloseSessionRequest { SessionId = ctx.SessionId, ClientCorrelationId = CreateCorrelationId() },
-                        cancellationToken)
-                    .ConfigureAwait(false);
-            }
-            catch { /* best-effort */ }
-        }
-
-        Task[] streamTasks = openedSessions.Select(RunStreamAsync).ToArray();
-        await Task.WhenAll(streamTasks).ConfigureAwait(false);
-
-        double steadyElapsedSeconds = (firstSteadyEventUtc.HasValue && lastSteadyEventUtc.HasValue)
-            ? (lastSteadyEventUtc.Value - firstSteadyEventUtc.Value).TotalSeconds
-            : 0;
-        double eventsPerSecond = steadyElapsedSeconds > 0 ? steadyEvents / steadyElapsedSeconds : 0;
-        double dataChangeEventsPerSecond = steadyElapsedSeconds > 0
-            ? steadyDataChangeEvents / steadyElapsedSeconds
-            : 0;
-
-        double[] latencySnapshot;
-        lock (latencyLock) { latencySnapshot = endToEndLatencyMs.ToArray(); }
-
-        object stats = new
-        {
-            language = "dotnet",
-            command = "bench-stream-events",
-            endpoint = arguments.GetOptional("endpoint") ?? "(default)",
-            clientName,
-            sessionCount,
-            bulkSize,
-            durationSeconds,
-            warmupSeconds,
-            allAttributes,
-            steadyElapsedSeconds = Math.Round(steadyElapsedSeconds, 3),
-            subscribedTagCount = totalSubscribedTagCount,
-            subscribeFailures = totalSubscribeFailures,
-            warmupEvents,
-            steadyEvents,
-            steadyDataChangeEvents,
-            eventsPerSecond = Math.Round(eventsPerSecond, 2),
-            dataChangeEventsPerSecond = Math.Round(dataChangeEventsPerSecond, 2),
-            drainedFaultCount = totalDrainedFaultCount,
-            endToEndLatencyMs = new
-            {
-                p50 = Percentile(latencySnapshot, 0.50),
-                p95 = Percentile(latencySnapshot, 0.95),
-                p99 = Percentile(latencySnapshot, 0.99),
-                max = latencySnapshot.Length > 0 ? Math.Round(latencySnapshot.Max(), 3) : 0,
-                mean = latencySnapshot.Length > 0 ? Math.Round(latencySnapshot.Average(), 3) : 0,
-                sampleCount = latencySnapshot.Length,
-            },
-        };
-        output.WriteLine(JsonSerializer.Serialize(stats, JsonOptions));
-        return 0;
-    }
-
    /// <summary>
    /// Computes the requested percentile from an unsorted latency sample using
    /// nearest-rank with linear interpolation. Rounds to 3 decimal places to
@@ -1202,35 +973,6 @@ public static class MxGatewayClientCli
        return Math.Round(value, 3);
    }

-    /// <summary>
-    ///     Parses the bulk-write CLI's <c>--values</c> list. All entries share
-    ///     the single <c>--type</c> argument; the comma-separated values are
-    ///     each parsed via <see cref="ParseValue"/> on a per-entry basis. This
-    ///     keeps the CLI simple for e2e use (one type, N values) — callers
-    ///     that need heterogeneous types per entry should drive the library
-    ///     directly.
-    /// </summary>
-    private static IReadOnlyList<MxValue> ParseValuesList(CliArguments arguments)
-    {
-        string type = arguments.GetRequired("type");
-        string[] values = ParseStringList(arguments.GetRequired("values")).ToArray();
-        MxValue[] result = new MxValue[values.Length];
-        for (int i = 0; i < values.Length; i++)
-        {
-            result[i] = ParseValue(type, values[i]);
-        }
-        return result;
-    }
-
-    private static void EnsureSameLength(int handles, int values)
-    {
-        if (handles != values)
-        {
-            throw new ArgumentException(
-                $"Bulk write requires the same number of --item-handles ({handles}) and --values ({values}).");
-        }
-    }
-
    private static Task<int> WriteAsync(
        CliArguments arguments,
        IMxGatewayCliClient client,
@@ -1337,14 +1079,8 @@ public static class MxGatewayClientCli
        }
        catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested)
        {
-            // Client.Dotnet-017: the supplied cancellation token covers both the
-            // user's --timeout wall-clock budget (via CreateCancellation's
-            // CancelAfter) and external Ctrl+C / parent CTS cancellation. All
-            // three are graceful completion modes for a finite-window event
-            // collector: emit the events that arrived before the window closed
-            // and exit 0. The events list is well-formed at this point; the
-            // aggregate JSON below still runs. This matches how the Go, Rust,
-            // Python, and Java CLIs treat their equivalent timeouts.
+            // Client.Dotnet-017: graceful end-of-window completion mode for a
+            // finite-window event collector. Emit aggregate JSON below and exit 0.
        }

        if (json && !jsonLines)
@@ -1506,7 +1242,7 @@ public static class MxGatewayClientCli
                        Kind = MxCommandKind.Register,
                        Register = new RegisterCommand { ClientName = arguments.GetOptional("client-name") ?? "mxgw-dotnet-smoke" },
                    },
-                    RequireRegisterServerHandle,
+                    reply => reply.Register?.ServerHandle ?? reply.ReturnValue.Int32Value,
                    commandReplies,
                    cancellationToken)
                .ConfigureAwait(false);
@@ -1524,7 +1260,7 @@ public static class MxGatewayClientCli
                            ItemDefinition = arguments.GetRequired("item"),
                        },
                    },
-                    RequireAddItemItemHandle,
+                    reply => reply.AddItem?.ItemHandle ?? reply.ReturnValue.Int32Value,
                    commandReplies,
                    cancellationToken)
                .ConfigureAwait(false);
@@ -1656,41 +1392,6 @@ public static class MxGatewayClientCli
        return reply;
    }

-    /// <summary>
-    /// Returns the server handle from a successful <c>register</c> reply, or throws
-    /// <see cref="MxGatewayException"/> when the typed <see cref="MxCommandReply.Register"/>
-    /// payload is absent. Mirrors the SDK-level <see cref="MxGatewaySession.RegisterAsync"/>
-    /// contract: a successful reply without the typed payload is a gateway protocol
-    /// error, not a license to fall through to <c>ReturnValue.Int32Value</c> (which is 0
-    /// when the reply carries no return value).
-    /// </summary>
-    private static int RequireRegisterServerHandle(MxCommandReply reply)
-    {
-        return reply.Register?.ServerHandle
-            ?? throw CreateMissingPayloadException(reply, "register");
-    }
-
-    /// <summary>
-    /// Returns the item handle from a successful <c>add_item</c> reply, or throws
-    /// <see cref="MxGatewayException"/> when the typed <see cref="MxCommandReply.AddItem"/>
-    /// payload is absent. See <see cref="RequireRegisterServerHandle"/> for the rationale.
-    /// </summary>
-    private static int RequireAddItemItemHandle(MxCommandReply reply)
-    {
-        return reply.AddItem?.ItemHandle
-            ?? throw CreateMissingPayloadException(reply, "add_item");
-    }
-
-    private static MxGatewayException CreateMissingPayloadException(
-        MxCommandReply reply,
-        string expectedPayload)
-    {
-        return new MxGatewayException(
-            $"Gateway reply for command kind={reply.Kind} reported success but is missing "
-            + $"the required '{expectedPayload}' payload; cannot resolve a handle. "
-            + $"session={reply.SessionId}; correlation={reply.CorrelationId}");
-    }
-
    private static MxCommandRequest CreateCommandRequest(
        string sessionId,
        MxCommand command)
@@ -1787,12 +1488,12 @@ public static class MxGatewayClientCli
        return ParseValue(arguments.GetRequired("type"), arguments.GetRequired("value"));
    }

-    private static MxValue ParseValue(string typeName, string value)
+    private static MxValue ParseValue(string type, string value)
    {
-        string type = typeName.ToLowerInvariant();
+        string normalisedType = type.ToLowerInvariant();
        string[] values = value.Split(',', StringSplitOptions.TrimEntries);

-        return type switch
+        return normalisedType switch
        {
            "bool" or "boolean" => bool.Parse(value).ToMxValue(),
            "bool-array" or "boolean-array" => values.Select(bool.Parse).ToArray().ToMxValue(),
@@ -1811,7 +1512,7 @@ public static class MxGatewayClientCli
                .Select(item => DateTimeOffset.Parse(item, CultureInfo.InvariantCulture, DateTimeStyles.AssumeUniversal))
                .ToArray()
                .ToMxValue(),
-            _ => throw new ArgumentException($"Unsupported MX value type '{type}'."),
+            _ => throw new ArgumentException($"Unsupported MX value type '{normalisedType}'."),
        };
    }

@@ -2028,7 +1729,6 @@ public static class MxGatewayClientCli
            or "write-secured-bulk"
            or "write-secured2-bulk"
            or "bench-read-bulk"
-            or "bench-stream-events"
            or "stream-events"
            or "stream-alarms"
            or "acknowledge-alarm"
@@ -2082,13 +1782,14 @@ public static class MxGatewayClientCli
        writer.WriteLine("mxgw-dotnet register --session-id <id> --client-name <name> [--json]");
        writer.WriteLine("mxgw-dotnet add-item --session-id <id> --server-handle <n> --item <ref> [--json]");
        writer.WriteLine("mxgw-dotnet advise --session-id <id> --server-handle <n> --item-handle <n> [--json]");
+        writer.WriteLine("mxgw-dotnet subscribe-bulk --session-id <id> --server-handle <n> --items <ref,ref> [--json]");
+        writer.WriteLine("mxgw-dotnet unsubscribe-bulk --session-id <id> --server-handle <n> --item-handles <n,n> [--json]");
        writer.WriteLine("mxgw-dotnet read-bulk --session-id <id> --server-handle <n> --items <ref,ref> [--timeout-ms <n>] [--json]");
        writer.WriteLine("mxgw-dotnet write-bulk --session-id <id> --server-handle <n> --item-handles <n,n> --type <type> --values <v,v> [--user-id <n>] [--json]");
        writer.WriteLine("mxgw-dotnet write2-bulk --session-id <id> --server-handle <n> --item-handles <n,n> --type <type> --values <v,v> [--timestamp <iso>] [--user-id <n>] [--json]");
        writer.WriteLine("mxgw-dotnet write-secured-bulk --session-id <id> --server-handle <n> --item-handles <n,n> --type <type> --values <v,v> --current-user-id <n> [--verifier-user-id <n>] [--json]");
-        writer.WriteLine("mxgw-dotnet write-secured2-bulk --session-id <id> --server-handle <n> --item-handles <n,n> --type <type> --values <v,v> [--timestamp <iso>] --current-user-id <n> [--verifier-user-id <n>] [--json]");
-        writer.WriteLine("mxgw-dotnet subscribe-bulk --session-id <id> --server-handle <n> --items <ref,ref> [--json]");
-        writer.WriteLine("mxgw-dotnet unsubscribe-bulk --session-id <id> --server-handle <n> --item-handles <n,n> [--json]");
+        writer.WriteLine("mxgw-dotnet write-secured2-bulk --session-id <id> --server-handle <n> --item-handles <n,n> --type <type> --values <v,v> --current-user-id <n> [--verifier-user-id <n>] [--timestamp <iso>] [--json]");
+        writer.WriteLine("mxgw-dotnet bench-read-bulk [--duration-seconds <n>] [--warmup-seconds <n>] [--bulk-size <n>] [--tag-start <n>] [--tag-prefix <s>] [--tag-attribute <s>] [--timeout-ms <n>] [--client-name <name>]");
        writer.WriteLine("mxgw-dotnet stream-events --session-id <id> [--max-events <n>] [--json]");
        writer.WriteLine("mxgw-dotnet stream-alarms [--filter-prefix <ref>] [--max-events <n>] [--json] [--jsonl]");
        writer.WriteLine("mxgw-dotnet acknowledge-alarm --reference <ref> [--comment <text>] [--operator <user>] [--json]");
@@ -1,3 +1,3 @@
-using MxGateway.Client.Cli;
+using ZB.MOM.WW.MxGateway.Client.Cli;

 return await MxGatewayClientCli.RunAsync(args, Console.Out, Console.Error);
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">

  <ItemGroup>
-    <ProjectReference Include="..\MxGateway.Client\MxGateway.Client.csproj" />
+    <ProjectReference Include="..\ZB.MOM.WW.MxGateway.Client\ZB.MOM.WW.MxGateway.Client.csproj" />
  </ItemGroup>

  <PropertyGroup>
@@ -0,0 +1,35 @@
+using Grpc.Core;
+using Grpc.Net.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;
+
+namespace ZB.MOM.WW.MxGateway.Client.Tests;
+
+/// <summary>
+/// Live smoke tests for the BrowseChildren RPC. Skipped by default; set
+/// MXGATEWAY_API_KEY and MXGATEWAY_ENDPOINT to run against a real gateway.
+/// </summary>
+public sealed class BrowseChildrenSmokeTests
+{
+    /// <summary>
+    /// Verifies that BrowseChildren returns a non-zero cache sequence and
+    /// a consistent children/child-has-children count from a live gateway.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact(Skip = "Set MXGATEWAY_API_KEY and MXGATEWAY_ENDPOINT to enable.")]
+    public async Task BrowseChildren_LiveGateway_ReturnsRootsWithCacheSequence()
+    {
+        string? apiKey = Environment.GetEnvironmentVariable("MXGATEWAY_API_KEY");
+        string endpoint = Environment.GetEnvironmentVariable("MXGATEWAY_ENDPOINT") ?? "http://localhost:5120";
+
+        Assert.False(string.IsNullOrEmpty(apiKey), "MXGATEWAY_API_KEY must be set.");
+
+        using GrpcChannel channel = GrpcChannel.ForAddress(endpoint);
+        GalaxyRepository.GalaxyRepositoryClient client = new(channel);
+
+        Metadata headers = new() { { "authorization", $"Bearer {apiKey}" } };
+        BrowseChildrenReply reply = await client.BrowseChildrenAsync(new BrowseChildrenRequest(), headers);
+
+        Assert.True(reply.CacheSequence > 0UL);
+        Assert.Equal(reply.Children.Count, reply.ChildHasChildren.Count);
+    }
+}
@@ -1,21 +1,17 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 /// <summary>
 /// Fake Galaxy Repository client transport for testing.
 /// </summary>
 internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions options) : IGalaxyRepositoryClientTransport
 {
-    /// <summary>
-    /// Gets the gateway client options.
-    /// </summary>
+    /// <inheritdoc />
    public MxGatewayClientOptions Options { get; } = options;

-    /// <summary>
-    /// Gets the raw gRPC client; always null for the fake.
-    /// </summary>
+    /// <inheritdoc />
    public GalaxyRepository.GalaxyRepositoryClient? RawClient => null;

    /// <summary>
@@ -48,6 +44,7 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
    /// </summary>
    public DiscoverHierarchyReply DiscoverHierarchyReply { get; set; } = new();

+    /// <summary>Gets the queue of discover hierarchy replies; dequeued in FIFO order.</summary>
    public Queue<DiscoverHierarchyReply> DiscoverHierarchyReplies { get; } = new();

    /// <summary>
@@ -65,11 +62,7 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
    /// </summary>
    public Queue<Exception> DiscoverHierarchyExceptions { get; } = new();

-    /// <summary>
-    /// Records the request and either throws a queued exception or returns the configured reply.
-    /// </summary>
-    /// <param name="request">The TestConnectionRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public Task<TestConnectionReply> TestConnectionAsync(
        TestConnectionRequest request,
        CallOptions callOptions)
@@ -83,11 +76,7 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
        return Task.FromResult(TestConnectionReply);
    }

-    /// <summary>
-    /// Records the request and either throws a queued exception or returns the configured reply.
-    /// </summary>
-    /// <param name="request">The GetLastDeployTimeRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public Task<GetLastDeployTimeReply> GetLastDeployTimeAsync(
        GetLastDeployTimeRequest request,
        CallOptions callOptions)
@@ -101,11 +90,7 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
        return Task.FromResult(GetLastDeployTimeReply);
    }

-    /// <summary>
-    /// Records the request and either throws a queued exception or returns the configured reply.
-    /// </summary>
-    /// <param name="request">The DiscoverHierarchyRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public Task<DiscoverHierarchyReply> DiscoverHierarchyAsync(
        DiscoverHierarchyRequest request,
        CallOptions callOptions)
@@ -122,6 +107,35 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
                : DiscoverHierarchyReply);
    }

+    /// <summary>Records BrowseChildren RPC calls made by the client.</summary>
+    public List<(BrowseChildrenRequest Request, CallOptions CallOptions)> BrowseChildrenCalls { get; } = [];
+
+    /// <summary>Default reply returned from BrowseChildren when the queue is empty.</summary>
+    public BrowseChildrenReply BrowseChildrenReply { get; set; } = new();
+
+    /// <summary>Queue of replies returned from BrowseChildren; dequeued in FIFO order.</summary>
+    public Queue<BrowseChildrenReply> BrowseChildrenReplies { get; } = new();
+
+    /// <summary>Queue of exceptions to throw from BrowseChildren; dequeued in FIFO order.</summary>
+    public Queue<Exception> BrowseChildrenExceptions { get; } = new();
+
+    /// <inheritdoc />
+    public Task<BrowseChildrenReply> BrowseChildrenAsync(
+        BrowseChildrenRequest request,
+        CallOptions callOptions)
+    {
+        BrowseChildrenCalls.Add((request, callOptions));
+        if (BrowseChildrenExceptions.TryDequeue(out Exception? exception))
+        {
+            return Task.FromException<BrowseChildrenReply>(exception);
+        }
+
+        return Task.FromResult(
+            BrowseChildrenReplies.TryDequeue(out BrowseChildrenReply? reply)
+                ? reply
+                : BrowseChildrenReply);
+    }
+
    /// <summary>
    /// Gets the list of WatchDeployEvents RPC calls made by the client.
    /// </summary>
@@ -143,11 +157,7 @@ internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions optio
    /// </summary>
    public Func<CancellationToken, Task>? WatchDeployEventsBeforeYield { get; set; }

-    /// <summary>
-    /// Records the request and streams events, checking for queued exceptions and calling WatchDeployEventsBeforeYield before each event.
-    /// </summary>
-    /// <param name="request">The WatchDeployEventsRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public async IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
        WatchDeployEventsRequest request,
        CallOptions callOptions)
@@ -1,7 +1,7 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 /// <summary>
 /// Fake implementation of IMxGatewayClientTransport for testing.
@@ -11,14 +11,10 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
    private readonly Queue<MxCommandReply> _invokeReplies = new();
    private readonly List<MxEvent> _events = [];

-    /// <summary>
-    /// Gets the gateway client options.
-    /// </summary>
+    /// <inheritdoc />
    public MxGatewayClientOptions Options { get; } = options;

-    /// <summary>
-    /// Gets null, since this is a test fake without a real gRPC client.
-    /// </summary>
+    /// <inheritdoc />
    public MxAccessGateway.MxAccessGatewayClient? RawClient => null;

    /// <summary>
@@ -46,6 +42,11 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
    /// </summary>
    public List<(AcknowledgeAlarmRequest Request, CallOptions CallOptions)> AcknowledgeAlarmCalls { get; } = [];

+    /// <summary>
+    /// Gets the list of captured QueryActiveAlarmsAsync calls.
+    /// </summary>
+    public List<(QueryActiveAlarmsRequest Request, CallOptions CallOptions)> QueryActiveAlarmsCalls { get; } = [];
+
    /// <summary>
    /// Gets the list of captured StreamAlarmsAsync calls.
    /// </summary>
@@ -58,6 +59,7 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx

    private readonly Queue<AcknowledgeAlarmReply> _acknowledgeReplies = new();
    private readonly List<ActiveAlarmSnapshot> _activeAlarmSnapshots = [];
+    private readonly List<AlarmFeedMessage> _alarmFeedMessages = [];

    /// <summary>
    /// Gets or sets the reply to return from OpenSessionAsync.
@@ -91,29 +93,12 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
    /// </summary>
    public Queue<Exception> CloseSessionExceptions { get; } = new();

-    /// <summary>
-    /// Gets or sets a value indicating whether thrown <see cref="RpcException"/>s are mapped
-    /// to <see cref="MxGatewayException"/> the way the production gRPC transport does. Lets
-    /// retry tests exercise the wrapped-exception predicate branch that runs in production.
-    /// </summary>
-    public bool MapTransportExceptions { get; set; }
-
-    /// <summary>
-    /// Gets or sets an optional hook awaited inside CloseSessionAsync after the call is
-    /// recorded; lets tests pause a close mid-flight to observe concurrent dispose.
-    /// </summary>
-    public Func<Task>? CloseSessionHook { get; set; }
-
    /// <summary>
    /// Gets the queue of exceptions to throw from InvokeAsync.
    /// </summary>
    public Queue<Exception> InvokeExceptions { get; } = new();

-    /// <summary>
-    /// Verifies that the OpenSessionAsync call is recorded and returns the configured reply.
-    /// </summary>
-    /// <param name="request">The OpenSessionRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public Task<OpenSessionReply> OpenSessionAsync(
        OpenSessionRequest request,
        CallOptions callOptions)
@@ -121,41 +106,27 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
        OpenSessionCalls.Add((request, callOptions));
        if (OpenSessionExceptions.TryDequeue(out Exception? exception))
        {
-            throw Translate(exception, callOptions);
+            throw exception;
        }

        return Task.FromResult(OpenSessionReply);
    }

-    /// <summary>
-    /// Verifies that the CloseSessionAsync call is recorded and returns the configured reply.
-    /// </summary>
-    /// <param name="request">The CloseSessionRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
-    public async Task<CloseSessionReply> CloseSessionAsync(
+    /// <inheritdoc />
+    public Task<CloseSessionReply> CloseSessionAsync(
        CloseSessionRequest request,
        CallOptions callOptions)
    {
        CloseSessionCalls.Add((request, callOptions));
-
-        if (CloseSessionHook is not null)
-        {
-            await CloseSessionHook().ConfigureAwait(false);
-        }
-
        if (CloseSessionExceptions.TryDequeue(out Exception? exception))
        {
-            throw Translate(exception, callOptions);
+            throw exception;
        }

-        return CloseSessionReply;
+        return Task.FromResult(CloseSessionReply);
    }

-    /// <summary>
-    /// Verifies that the InvokeAsync call is recorded and returns the next enqueued reply.
-    /// </summary>
-    /// <param name="request">The MxCommandRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public Task<MxCommandReply> InvokeAsync(
        MxCommandRequest request,
        CallOptions callOptions)
@@ -163,17 +134,13 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
        InvokeCalls.Add((request, callOptions));
        if (InvokeExceptions.TryDequeue(out Exception? exception))
        {
-            throw Translate(exception, callOptions);
+            throw exception;
        }

        return Task.FromResult(_invokeReplies.Dequeue());
    }

-    /// <summary>
-    /// Verifies that the StreamEventsAsync call is recorded and yields all enqueued events.
-    /// </summary>
-    /// <param name="request">The StreamEventsRequest to process.</param>
-    /// <param name="callOptions">Call options specifying RPC behavior.</param>
+    /// <inheritdoc />
    public async IAsyncEnumerable<MxEvent> StreamEventsAsync(
        StreamEventsRequest request,
        CallOptions callOptions)
@@ -206,9 +173,7 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
        _events.Add(gatewayEvent);
    }

-    /// <summary>
-    /// Records the acknowledge call and returns the next enqueued reply (or default).
-    /// </summary>
+    /// <inheritdoc />
    public Task<AcknowledgeAlarmReply> AcknowledgeAlarmAsync(
        AcknowledgeAlarmRequest request,
        CallOptions callOptions)
@@ -216,7 +181,7 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
        AcknowledgeAlarmCalls.Add((request, callOptions));
        if (AcknowledgeAlarmExceptions.TryDequeue(out Exception? exception))
        {
-            throw Translate(exception, callOptions);
+            throw exception;
        }

        return Task.FromResult(_acknowledgeReplies.Count > 0
@@ -229,49 +194,54 @@ internal sealed class FakeGatewayTransport(MxGatewayClientOptions options) : IMx
            });
    }

-    /// <summary>
-    /// Records the call and yields each enqueued snapshot as an active-alarm
-    /// feed message, then a snapshot-complete sentinel.
-    /// </summary>
+    /// <inheritdoc />
+    public async IAsyncEnumerable<ActiveAlarmSnapshot> QueryActiveAlarmsAsync(
+        QueryActiveAlarmsRequest request,
+        CallOptions callOptions)
+    {
+        QueryActiveAlarmsCalls.Add((request, callOptions));
+
+        foreach (ActiveAlarmSnapshot snapshot in _activeAlarmSnapshots)
+        {
+            callOptions.CancellationToken.ThrowIfCancellationRequested();
+            await Task.Yield();
+            yield return snapshot;
+        }
+    }
+
+    /// <summary>Enqueues an acknowledge reply.</summary>
+    /// <param name="reply">The acknowledge reply to enqueue.</param>
+    public void AddAcknowledgeReply(AcknowledgeAlarmReply reply)
+    {
+        _acknowledgeReplies.Enqueue(reply);
+    }
+
+    /// <summary>Enqueues a snapshot to be yielded from QueryActiveAlarmsAsync.</summary>
+    /// <param name="snapshot">The snapshot to enqueue.</param>
+    public void AddActiveAlarmSnapshot(ActiveAlarmSnapshot snapshot)
+    {
+        _activeAlarmSnapshots.Add(snapshot);
+    }
+
+    /// <inheritdoc />
    public async IAsyncEnumerable<AlarmFeedMessage> StreamAlarmsAsync(
        StreamAlarmsRequest request,
        CallOptions callOptions)
    {
        StreamAlarmsCalls.Add((request, callOptions));

-        foreach (ActiveAlarmSnapshot snapshot in _activeAlarmSnapshots)
+        foreach (AlarmFeedMessage message in _alarmFeedMessages)
        {
            callOptions.CancellationToken.ThrowIfCancellationRequested();
            await Task.Yield();
-            yield return new AlarmFeedMessage { ActiveAlarm = snapshot };
+            yield return message;
+        }
    }

-        yield return new AlarmFeedMessage { SnapshotComplete = true };
-    }
-
-    /// <summary>Enqueues an acknowledge reply.</summary>
-    public void AddAcknowledgeReply(AcknowledgeAlarmReply reply)
+    /// <summary>Enqueues an alarm feed message to be yielded from StreamAlarmsAsync.</summary>
+    /// <param name="message">The alarm feed message to enqueue.</param>
+    public void AddAlarmFeedMessage(AlarmFeedMessage message)
    {
-        _acknowledgeReplies.Enqueue(reply);
-    }
-
-    /// <summary>Enqueues a snapshot yielded from StreamAlarmsAsync as an active-alarm message.</summary>
-    public void AddActiveAlarmSnapshot(ActiveAlarmSnapshot snapshot)
-    {
-        _activeAlarmSnapshots.Add(snapshot);
-    }
-
-    /// <summary>
-    /// Maps a queued exception the way the production gRPC transport does when
-    /// <see cref="MapTransportExceptions"/> is set; otherwise returns it unchanged.
-    /// </summary>
-    private Exception Translate(Exception exception, CallOptions callOptions)
-    {
-        if (MapTransportExceptions && exception is RpcException rpcException)
-        {
-            return RpcExceptionMapper.Map(rpcException, callOptions.CancellationToken);
-        }
-
-        return exception;
+        _alarmFeedMessages.Add(message);
    }
 }
@@ -1,14 +1,15 @@
 using Google.Protobuf.WellKnownTypes;
 using Grpc.Core;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class GalaxyRepositoryClientTests
 {
    /// <summary>
    /// Verifies that TestConnectionAsync attaches the API key in request metadata and returns the Ok flag.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task TestConnectionAsync_AttachesApiKeyMetadataAndReturnsOkFlag()
    {
@@ -27,6 +28,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that TestConnectionAsync returns false when the server reports NotOk.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task TestConnectionAsync_ReturnsFalseWhenServerReportsNotOk()
    {
@@ -42,6 +44,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that GetLastDeployTimeAsync returns null when the server reports not present.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task GetLastDeployTimeAsync_ReturnsNullWhenNotPresent()
    {
@@ -58,6 +61,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that GetLastDeployTimeAsync returns the timestamp when the server reports it present.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task GetLastDeployTimeAsync_ReturnsTimestampWhenPresent()
    {
@@ -79,6 +83,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that DiscoverHierarchyAsync returns the objects from the server reply.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task DiscoverHierarchyAsync_ReturnsObjectsFromReply()
    {
@@ -141,6 +146,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that DiscoverHierarchyAsync propagates cancellation tokens to the transport.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task DiscoverHierarchyAsync_PropagatesCancellationToTransport()
    {
@@ -161,6 +167,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that TestConnectionAsync retries on transient gRPC failures.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task DiscoverHierarchyAsync_WithRepeatedPageToken_ThrowsProtocolError()
    {
@@ -181,6 +188,10 @@ public sealed class GalaxyRepositoryClientTests
        Assert.Contains("repeated page token", exception.Message, StringComparison.Ordinal);
    }

+    /// <summary>
+    /// Verifies that DiscoverHierarchyAsync maps typed filter options correctly to the request.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task DiscoverHierarchyAsync_WithOptions_MapsTypedFilters()
    {
@@ -212,6 +223,10 @@ public sealed class GalaxyRepositoryClientTests
        Assert.True(request.HistorizedOnly);
    }

+    /// <summary>
+    /// Verifies that TestConnectionAsync retries on transient gRPC failures.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task TestConnectionAsync_RetriesOnTransientGrpcFailure()
    {
@@ -229,6 +244,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that DiscoverHierarchyAsync retries on transient gRPC failures.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task DiscoverHierarchyAsync_RetriesOnTransientGrpcFailure()
    {
@@ -245,6 +261,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that WatchDeployEventsAsync delivers the bootstrap event.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task WatchDeployEventsAsync_DeliversBootstrapEvent()
    {
@@ -281,6 +298,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that WatchDeployEventsAsync delivers multiple events in order.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task WatchDeployEventsAsync_DeliversMultipleEventsInOrder()
    {
@@ -319,6 +337,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that WatchDeployEventsAsync stops iteration cleanly when cancelled.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task WatchDeployEventsAsync_CancellationStopsIterationCleanly()
    {
@@ -363,6 +382,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that WatchDeployEventsAsync throws ObjectDisposedException after the client is disposed.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task WatchDeployEventsAsync_ThrowsAfterDisposal()
    {
@@ -378,6 +398,7 @@ public sealed class GalaxyRepositoryClientTests
    /// <summary>
    /// Verifies that TestConnectionAsync throws ObjectDisposedException after the client is disposed.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task TestConnectionAsync_ThrowsAfterDisposal()
    {
@@ -0,0 +1,228 @@
+using Grpc.Core;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;
+
+namespace ZB.MOM.WW.MxGateway.Client.Tests;
+
+/// <summary>
+/// Tests for the <see cref="LazyBrowseNode"/> walker over the BrowseChildren RPC.
+/// </summary>
+public sealed class LazyBrowseNodeTests
+{
+    /// <summary>
+    /// Verifies that calling BrowseAsync with no parent returns the root nodes
+    /// from the first BrowseChildren reply and surfaces the per-child has-children hint.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Browse_NoParent_ReturnsRoots()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(1, "Plant", isArea: true), BuildObject(2, "Other")],
+            childHasChildren: [true, false],
+            cacheSequence: 1));
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+
+        Assert.Equal(2, roots.Count);
+        Assert.Equal("Plant", roots[0].Object.TagName);
+        Assert.True(roots[0].HasChildrenHint);
+        Assert.False(roots[0].IsExpanded);
+        Assert.Equal("Other", roots[1].Object.TagName);
+        Assert.False(roots[1].HasChildrenHint);
+        Assert.False(roots[1].IsExpanded);
+    }
+
+    /// <summary>
+    /// Verifies that ExpandAsync populates Children and marks the node expanded after one RPC.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Expand_PopulatesChildrenAndMarksExpanded()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(1, "Plant", isArea: true)],
+            childHasChildren: [true],
+            cacheSequence: 1));
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(10, "Line1")],
+            childHasChildren: [false],
+            cacheSequence: 1));
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+        await roots[0].ExpandAsync();
+
+        Assert.True(roots[0].IsExpanded);
+        Assert.Single(roots[0].Children);
+        Assert.Equal("Line1", roots[0].Children[0].Object.TagName);
+        Assert.Equal(2, transport.BrowseChildrenCalls.Count);
+    }
+
+    /// <summary>
+    /// Verifies that a second ExpandAsync call is a no-op and issues no additional RPC.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Expand_CalledTwice_NoSecondRpc()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(1, "Plant", isArea: true)],
+            childHasChildren: [true],
+            cacheSequence: 1));
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(10, "Line1")],
+            childHasChildren: [false],
+            cacheSequence: 1));
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+        await roots[0].ExpandAsync();
+        await roots[0].ExpandAsync();
+
+        Assert.Equal(2, transport.BrowseChildrenCalls.Count);
+    }
+
+    /// <summary>
+    /// Verifies that an RPC failure (NotFound) during expand is wrapped in MxGatewayException.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Expand_UnknownParent_ThrowsMxGatewayException()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(1, "Plant", isArea: true)],
+            childHasChildren: [true],
+            cacheSequence: 1));
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+
+        // Queue the failure for the upcoming ExpandAsync call so it consumes
+        // the exception on its first RPC rather than the BrowseAsync above.
+        transport.BrowseChildrenExceptions.Enqueue(
+            new MxGatewayException(
+                "Parent not found",
+                new RpcException(new Status(StatusCode.NotFound, "Parent not found"))));
+
+        await Assert.ThrowsAsync<MxGatewayException>(async () => await roots[0].ExpandAsync());
+        Assert.False(roots[0].IsExpanded);
+        Assert.Empty(roots[0].Children);
+    }
+
+    /// <summary>
+    /// Verifies that ExpandAsync drains multi-page sibling replies and forwards the page token.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Expand_MultiPageSiblings_GathersAllPages()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        // Roots
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(7, "Plant", isArea: true)],
+            childHasChildren: [true],
+            cacheSequence: 1));
+        // First child page (2 children) with a next token
+        BrowseChildrenReply childPage1 = BuildReply(
+            children: [BuildObject(70, "ChildA"), BuildObject(71, "ChildB")],
+            childHasChildren: [false, false],
+            cacheSequence: 1);
+        childPage1.NextPageToken = "7:abc:2";
+        transport.BrowseChildrenReplies.Enqueue(childPage1);
+        // Second child page (1 child) with no next token
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(72, "ChildC")],
+            childHasChildren: [false],
+            cacheSequence: 1));
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+        await roots[0].ExpandAsync();
+
+        Assert.Equal(3, roots[0].Children.Count);
+        Assert.Equal(3, transport.BrowseChildrenCalls.Count);
+        Assert.Equal("7:abc:2", transport.BrowseChildrenCalls[2].Request.PageToken);
+    }
+
+    /// <summary>
+    /// Verifies that ten concurrent ExpandAsync calls issue exactly one RPC, not ten.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Expand_CalledConcurrently_OnlyFiresOneRpc()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(1, "Plant", isArea: true)],
+            childHasChildren: [true],
+            cacheSequence: 7));
+        transport.BrowseChildrenReplies.Enqueue(BuildReply(
+            children: [BuildObject(2, "Mixer_001")],
+            childHasChildren: [false],
+            cacheSequence: 7));
+
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+        IReadOnlyList<LazyBrowseNode> roots = await client.BrowseAsync();
+
+        // Fire ten concurrent expands of the same node.
+        Task[] tasks = Enumerable.Range(0, 10)
+            .Select(_ => roots[0].ExpandAsync())
+            .ToArray();
+        await Task.WhenAll(tasks);
+
+        Assert.True(roots[0].IsExpanded);
+        Assert.Single(roots[0].Children);
+        // 1 roots fetch + exactly 1 expand fetch = 2 total
+        Assert.Equal(2, transport.BrowseChildrenCalls.Count);
+    }
+
+    /// <summary>
+    /// Verifies that BrowseChildrenOptions filter fields are forwarded to the BrowseChildren request.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Browse_WithFilter_ForwardsToRequest()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        await client.BrowseAsync(new BrowseChildrenOptions
+        {
+            TagNameGlob = "Mixer*",
+            AlarmBearingOnly = true,
+        });
+
+        BrowseChildrenRequest request = Assert.Single(transport.BrowseChildrenCalls).Request;
+        Assert.Equal("Mixer*", request.TagNameGlob);
+        Assert.True(request.AlarmBearingOnly);
+    }
+
+    private static GalaxyObject BuildObject(int id, string tag, bool isArea = false)
+        => new() { GobjectId = id, TagName = tag, BrowseName = tag, IsArea = isArea };
+
+    private static BrowseChildrenReply BuildReply(
+        IReadOnlyList<GalaxyObject> children,
+        IReadOnlyList<bool> childHasChildren,
+        ulong cacheSequence)
+    {
+        BrowseChildrenReply reply = new() { TotalChildCount = children.Count, CacheSequence = cacheSequence };
+        reply.Children.AddRange(children);
+        reply.ChildHasChildren.AddRange(childHasChildren);
+        return reply;
+    }
+
+    private static GalaxyRepositoryClient CreateClient(FakeGalaxyRepositoryTransport transport)
+        => new(transport.Options, transport);
+
+    private static FakeGalaxyRepositoryTransport CreateTransport()
+        => new(new MxGatewayClientOptions
+        {
+            Endpoint = new Uri("http://localhost:5000"),
+            ApiKey = "test-api-key",
+        });
+}
@@ -1,8 +1,8 @@
 using Google.Protobuf;
-using MxGateway.Client;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxCommandReplyExtensionsTests
 {
@@ -1,16 +1,18 @@
 using Google.Protobuf.WellKnownTypes;
 using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 /// <summary>
-///     Pins the .NET SDK surface for the alarm RPCs:
+///     PR E.2 — pins the .NET SDK surface for the new alarm RPCs:
 ///     <see cref="MxGatewayClient.AcknowledgeAlarmAsync"/> and
-///     <see cref="MxGatewayClient.StreamAlarmsAsync"/>.
+///     <see cref="MxGatewayClient.QueryActiveAlarmsAsync"/>.
 /// </summary>
 public sealed class MxGatewayClientAlarmsTests
 {
+    /// <summary>AcknowledgeAlarmAsync records request and returns reply.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task AcknowledgeAlarmAsync_RecordsRequestShapeAndReturnsReply()
    {
@@ -46,6 +48,8 @@ public sealed class MxGatewayClientAlarmsTests
        Assert.Equal("Bearer test-api-key", call.CallOptions.Headers?.GetValue("authorization"));
    }

+    /// <summary>AcknowledgeAlarmAsync honors cancellation.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task AcknowledgeAlarmAsync_HonorsCancellation()
    {
@@ -69,18 +73,22 @@ public sealed class MxGatewayClientAlarmsTests
                cancellation.Token));
    }

+    /// <summary>AcknowledgeAlarmAsync maps unauthenticated RPC exception to typed exception.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task AcknowledgeAlarmAsync_SurfacesRpcExceptionFromFakeTransportVerbatim_WhenMappingDisabled()
+    public async Task AcknowledgeAlarmAsync_MapsUnauthenticated_RpcException_ToTypedException()
    {
-        // Default FakeGatewayTransport.MapTransportExceptions is false, matching the
-        // historical pass-through shape: a thrown RpcException reaches the caller as
-        // RpcException rather than being mapped to a typed MxGatewayException. This
-        // test pins that shape so a future change can't silently flip it.
        FakeGatewayTransport transport = CreateTransport();
        transport.AcknowledgeAlarmExceptions.Enqueue(
            new RpcException(new Status(StatusCode.Unauthenticated, "expired key")));
        await using MxGatewayClient client = CreateClient(transport);

+        // Note: the FakeGatewayTransport surfaces RpcException directly (it does not run
+        // through GrpcMxGatewayClientTransport's mapping); the fake's contract here is to
+        // pass the exception verbatim. RpcException → typed exception mapping is covered
+        // in the GrpcMxGatewayClientTransport-level tests; the SDK-level test pins the
+        // pass-through shape so a future migration to direct mapping won't silently
+        // change observable behaviour.
        var ex = await Assert.ThrowsAsync<RpcException>(
            () => client.AcknowledgeAlarmAsync(new AcknowledgeAlarmRequest
            {
@@ -91,73 +99,57 @@ public sealed class MxGatewayClientAlarmsTests
        Assert.Equal(StatusCode.Unauthenticated, ex.StatusCode);
    }

+    /// <summary>QueryActiveAlarmsAsync streams enqueued snapshots.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task AcknowledgeAlarmAsync_MapsUnauthenticated_RpcException_ToTypedException()
-    {
-        // Production parity: GrpcMxGatewayClientTransport.AcknowledgeAlarmAsync runs
-        // every thrown RpcException through RpcExceptionMapper.Map, so callers see
-        // MxGatewayAuthenticationException (for Unauthenticated) rather than the raw
-        // RpcException. The fake transport reproduces that mapping when
-        // MapTransportExceptions is set, letting this SDK-level test cover the same
-        // observable behaviour without standing up a real gRPC channel.
-        FakeGatewayTransport transport = CreateTransport();
-        transport.MapTransportExceptions = true;
-        transport.AcknowledgeAlarmExceptions.Enqueue(
-            new RpcException(new Status(StatusCode.Unauthenticated, "expired key")));
-        await using MxGatewayClient client = CreateClient(transport);
-
-        var ex = await Assert.ThrowsAsync<MxGatewayAuthenticationException>(
-            () => client.AcknowledgeAlarmAsync(new AcknowledgeAlarmRequest
-            {
-                AlarmFullReference = "Tank01.Level.HiHi",
-                Comment = string.Empty,
-                OperatorUser = "alice",
-            }));
-        Assert.Equal(StatusCode.Unauthenticated, ex.StatusCode);
-    }
-
-    [Fact]
-    public async Task StreamAlarmsAsync_StreamsSnapshotThenSnapshotComplete()
+    public async Task QueryActiveAlarmsAsync_StreamsEnqueuedSnapshots()
    {
        FakeGatewayTransport transport = CreateTransport();
        transport.AddActiveAlarmSnapshot(MakeSnapshot("Tank01.Level.HiHi", AlarmConditionState.Active));
        transport.AddActiveAlarmSnapshot(MakeSnapshot("Tank02.Level.HiHi", AlarmConditionState.ActiveAcked));
        await using MxGatewayClient client = CreateClient(transport);

-        List<AlarmFeedMessage> messages = [];
-        await foreach (AlarmFeedMessage message in client.StreamAlarmsAsync(new StreamAlarmsRequest()))
+        List<ActiveAlarmSnapshot> snapshots = [];
+        await foreach (ActiveAlarmSnapshot snapshot in client.QueryActiveAlarmsAsync(new QueryActiveAlarmsRequest
        {
-            messages.Add(message);
+            SessionId = "session-fixture",
+        }))
+        {
+            snapshots.Add(snapshot);
        }

-        Assert.Equal(3, messages.Count);
-        Assert.Equal("Tank01.Level.HiHi", messages[0].ActiveAlarm.AlarmFullReference);
-        Assert.Equal(AlarmConditionState.Active, messages[0].ActiveAlarm.CurrentState);
-        Assert.Equal(AlarmConditionState.ActiveAcked, messages[1].ActiveAlarm.CurrentState);
-        Assert.True(messages[2].SnapshotComplete);
-        Assert.Single(transport.StreamAlarmsCalls);
+        Assert.Equal(2, snapshots.Count);
+        Assert.Equal("Tank01.Level.HiHi", snapshots[0].AlarmFullReference);
+        Assert.Equal(AlarmConditionState.Active, snapshots[0].CurrentState);
+        Assert.Equal(AlarmConditionState.ActiveAcked, snapshots[1].CurrentState);
+        Assert.Single(transport.QueryActiveAlarmsCalls);
    }

+    /// <summary>QueryActiveAlarmsAsync passes filter prefix.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task StreamAlarmsAsync_PassesFilterPrefix()
+    public async Task QueryActiveAlarmsAsync_PassesFilterPrefix()
    {
        FakeGatewayTransport transport = CreateTransport();
        await using MxGatewayClient client = CreateClient(transport);

-        await foreach (AlarmFeedMessage _ in client.StreamAlarmsAsync(new StreamAlarmsRequest
+        await foreach (ActiveAlarmSnapshot _ in client.QueryActiveAlarmsAsync(new QueryActiveAlarmsRequest
        {
+            SessionId = "session-fixture",
            AlarmFilterPrefix = "Tank01.",
        }))
        {
-            // only the snapshot-complete sentinel; verifying the request passes through
+            // no snapshots enqueued; just verifying the request passes through
        }

-        var call = Assert.Single(transport.StreamAlarmsCalls);
+        var call = Assert.Single(transport.QueryActiveAlarmsCalls);
        Assert.Equal("Tank01.", call.Request.AlarmFilterPrefix);
    }

+    /// <summary>QueryActiveAlarmsAsync honors cancellation during enumeration.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task StreamAlarmsAsync_HonorsCancellationDuringEnumeration()
+    public async Task QueryActiveAlarmsAsync_HonorsCancellationDuringEnumeration()
    {
        FakeGatewayTransport transport = CreateTransport();
        transport.AddActiveAlarmSnapshot(MakeSnapshot("Tank01.Level.HiHi", AlarmConditionState.Active));
@@ -167,8 +159,8 @@ public sealed class MxGatewayClientAlarmsTests
        using CancellationTokenSource cancellation = new();
        await Assert.ThrowsAsync<OperationCanceledException>(async () =>
        {
-            await foreach (AlarmFeedMessage _ in client.StreamAlarmsAsync(
-                new StreamAlarmsRequest(),
+            await foreach (ActiveAlarmSnapshot _ in client.QueryActiveAlarmsAsync(
+                new QueryActiveAlarmsRequest { SessionId = "session-fixture" },
                cancellation.Token))
            {
                cancellation.Cancel();
@@ -1,9 +1,9 @@
 using Google.Protobuf.WellKnownTypes;
-using MxGateway.Client.Cli;
-using MxGateway.Contracts.Proto;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Client.Cli;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 /// <summary>Tests for the CLI command interface.</summary>
 public sealed class MxGatewayClientCliTests
@@ -24,6 +24,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that the version command with --json flag prints JSON protocol versions.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_VersionJson_PrintsJsonProtocolVersions()
    {
@@ -38,6 +39,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that the write command builds a write request and prints JSON reply.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_Write_BuildsWriteCommandAndPrintsJsonReply()
    {
@@ -83,6 +85,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that error output redacts sensitive API key values.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_ErrorOutput_RedactsApiKey()
    {
@@ -106,44 +109,8 @@ public sealed class MxGatewayClientCliTests
        Assert.Contains("[redacted]", error.ToString());
    }

-    /// <summary>
-    /// Verifies that error output redacts the API key even when it was sourced from
-    /// the <c>--api-key-env</c> environment variable rather than passed via
-    /// <c>--api-key</c> — the documented default credential path.
-    /// </summary>
-    [Fact]
-    public async Task RunAsync_ErrorOutput_RedactsApiKey_WhenSourcedFromEnvironmentVariable()
-    {
-        const string environmentVariableName = "MXGATEWAY_TEST_API_KEY_REDACT";
-        using var output = new StringWriter();
-        using var error = new StringWriter();
-
-        Environment.SetEnvironmentVariable(environmentVariableName, "env-secret-api-key");
-        try
-        {
-            int exitCode = await MxGatewayClientCli.RunAsync(
-                [
-                    "open-session",
-                    "--endpoint",
-                    "http://localhost:5000",
-                    "--api-key-env",
-                    environmentVariableName,
-                ],
-                output,
-                error,
-                _ => throw new InvalidOperationException("boom env-secret-api-key"));
-
-            Assert.Equal(1, exitCode);
-            Assert.DoesNotContain("env-secret-api-key", error.ToString());
-            Assert.Contains("[redacted]", error.ToString());
-        }
-        finally
-        {
-            Environment.SetEnvironmentVariable(environmentVariableName, null);
-        }
-    }
-
    /// <summary>Verifies that stream-events with max-events limit stops output in non-JSON format.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_StreamEvents_WithMaxEventsStopsNonJsonOutput()
    {
@@ -184,71 +151,9 @@ public sealed class MxGatewayClientCliTests
        Assert.DoesNotContain("ON_WRITE_COMPLETE", output.ToString());
    }

-    /// <summary>
-    ///     Client.Dotnet-017 regression: a finite-window event collector
-    ///     (<c>stream-events --timeout</c>) must exit 0 and emit the events
-    ///     that arrived before the timeout fired, instead of propagating the
-    ///     timeout-driven <see cref="OperationCanceledException"/> as an
-    ///     unhandled exception (exit code -532462766). The fix wraps the
-    ///     <c>await foreach</c> in a token-aware catch so the cancellation
-    ///     ends the foreach gracefully; the aggregated JSON output still runs.
-    /// </summary>
-    [Fact]
-    public async Task RunAsync_StreamEvents_WhenTimeoutFiresAfterEvents_EmitsCollectedEventsAndExitsZero()
-    {
-        using var output = new StringWriter();
-        using var error = new StringWriter();
-        FakeCliClient fakeClient = new();
-        fakeClient.Events.Add(new MxEvent
-        {
-            SessionId = "session-fixture",
-            Family = MxEventFamily.OnDataChange,
-            WorkerSequence = 1,
-        });
-        fakeClient.Events.Add(new MxEvent
-        {
-            SessionId = "session-fixture",
-            Family = MxEventFamily.OnDataChange,
-            WorkerSequence = 2,
-        });
-        // Park forever after yielding the configured events so the CLI's
-        // --timeout drives the cancellation path.
-        fakeClient.StreamHangAfterEvents = async token =>
-        {
-            await Task.Delay(Timeout.InfiniteTimeSpan, token).ConfigureAwait(false);
-        };
-
-        int exitCode = await MxGatewayClientCli.RunAsync(
-            [
-                "stream-events",
-                "--endpoint",
-                "http://localhost:5000",
-                "--api-key",
-                "test-api-key",
-                "--session-id",
-                "session-fixture",
-                "--json",
-                "--max-events",
-                "200",
-                "--timeout",
-                "1s",
-            ],
-            output,
-            error,
-            _ => fakeClient);
-
-        Assert.Equal(0, exitCode);
-        string json = output.ToString();
-        // Aggregate JSON output must run even though the foreach exited via
-        // cancellation, and it must contain both events that arrived first.
-        Assert.Contains("\"events\"", json);
-        Assert.Contains("\"workerSequence\":\"1\"", json);
-        Assert.Contains("\"workerSequence\":\"2\"", json);
-        Assert.Equal(string.Empty, error.ToString());
-    }
-

    /// <summary>Verifies that stream-alarms with --max-events stops output and distinguishes payload cases.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_StreamAlarms_WithMaxEventsStopsAndDistinguishesPayloadCases()
    {
@@ -288,6 +193,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that acknowledge-alarm builds a request and prints the JSON reply.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_AcknowledgeAlarm_BuildsRequestAndPrintsJsonReply()
    {
@@ -330,6 +236,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that smoke command closes opened session when a command fails.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_Smoke_WhenCommandFails_ClosesOpenedSession()
    {
@@ -361,6 +268,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that galaxy-test-connection command prints JSON reply.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_GalaxyTestConnection_PrintsJsonReply()
    {
@@ -391,6 +299,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that galaxy-discover command prints hierarchy summary.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_GalaxyDiscover_PrintsHierarchySummary()
    {
@@ -461,6 +370,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that galaxy-watch command prints text output for deploy events.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_GalaxyWatch_PrintsTextOutputForEvents()
    {
@@ -515,6 +425,7 @@ public sealed class MxGatewayClientCliTests
    }

    /// <summary>Verifies that galaxy-watch with --json emits one JSON object per event.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RunAsync_GalaxyWatch_JsonEmitsOneObjectPerEvent()
    {
@@ -549,139 +460,420 @@ public sealed class MxGatewayClientCliTests
        Assert.Contains("\"objectCount\": 99", text);
    }

-    /// <summary>Verifies that batch mode executes a single no-gateway command and writes the EOR sentinel.</summary>
+    /// <summary>Verifies that batch mode dispatches a single version command and emits the EOR sentinel.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task RunAsync_Batch_SingleVersionCommand_WritesOutputAndEorSentinel()
+    public async Task RunAsync_Batch_DispatchesVersionAndWritesEndOfRecord()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
-        using var stdin = new StringReader("version --json\n");
+        using var input = new StringReader("version --json\n");

        int exitCode = await MxGatewayClientCli.RunAsync(
            ["batch"],
            output,
            error,
            clientFactory: null,
-            standardInput: stdin);
+            standardInput: input);

        Assert.Equal(0, exitCode);
        string text = output.ToString();
-        Assert.Contains("\"gatewayProtocolVersion\"", text);
+        Assert.Contains("\"gatewayProtocolVersion\":3", text);
        Assert.Contains("__MXGW_BATCH_EOR__", text);
-        // Sentinel must appear after the output, not before.
-        int outputIdx = text.IndexOf("gatewayProtocolVersion", StringComparison.Ordinal);
-        int eorIdx = text.IndexOf("__MXGW_BATCH_EOR__", StringComparison.Ordinal);
-        Assert.True(outputIdx < eorIdx, "EOR sentinel must follow command output.");
+        // The EOR marker must come after the JSON output.
+        int jsonIndex = text.IndexOf("\"gatewayProtocolVersion\"", StringComparison.Ordinal);
+        int eorIndex = text.IndexOf("__MXGW_BATCH_EOR__", StringComparison.Ordinal);
+        Assert.True(jsonIndex >= 0 && eorIndex > jsonIndex);
        Assert.Equal(string.Empty, error.ToString());
    }

-    /// <summary>Verifies that batch mode processes two commands sequentially and writes two EOR sentinels.</summary>
+    /// <summary>Verifies that batch mode routes per-command errors to stdout as JSON between EOR markers.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task RunAsync_Batch_TwoVersionCommands_WritesTwoEorSentinels()
+    public async Task RunAsync_Batch_WritesErrorsToStdoutAsJson()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
-        // Two commands followed by EOF (end of string).
-        using var stdin = new StringReader("version\nversion --json\n");
+        // Unknown command should produce an error on the captured error stream,
+        // which batch mode re-emits to stdout inside the same delimited block.
+        using var input = new StringReader("nope-not-a-command\nversion\n");

        int exitCode = await MxGatewayClientCli.RunAsync(
            ["batch"],
            output,
            error,
            clientFactory: null,
-            standardInput: stdin);
+            standardInput: input);

        Assert.Equal(0, exitCode);
        string text = output.ToString();
+        // Two records → two EOR markers.
        int firstEor = text.IndexOf("__MXGW_BATCH_EOR__", StringComparison.Ordinal);
-        int secondEor = text.IndexOf("__MXGW_BATCH_EOR__", firstEor + 1, StringComparison.Ordinal);
-        Assert.True(firstEor >= 0, "First EOR sentinel must be present.");
-        Assert.True(secondEor > firstEor, "Second EOR sentinel must follow first.");
-        Assert.Equal(string.Empty, error.ToString());
-    }
-
-    /// <summary>Verifies that batch mode on EOF (empty stdin) exits 0 immediately without writing any sentinel.</summary>
-    [Fact]
-    public async Task RunAsync_Batch_EmptyStdin_ExitsZeroWithNoOutput()
-    {
-        using var output = new StringWriter();
-        using var error = new StringWriter();
-        using var stdin = new StringReader(string.Empty);
-
-        int exitCode = await MxGatewayClientCli.RunAsync(
-            ["batch"],
-            output,
-            error,
-            clientFactory: null,
-            standardInput: stdin);
-
-        Assert.Equal(0, exitCode);
-        Assert.Equal(string.Empty, output.ToString());
-        Assert.Equal(string.Empty, error.ToString());
+        int secondEor = text.IndexOf(
+            "__MXGW_BATCH_EOR__",
+            firstEor + 1,
+            StringComparison.Ordinal);
+        Assert.True(firstEor > 0);
+        Assert.True(secondEor > firstEor);
+        // The unknown-command error message must be on stdout (not on stderr).
+        Assert.Contains("nope-not-a-command", text);
+        Assert.DoesNotContain("nope-not-a-command", error.ToString());
+        // The follow-up `version` line should still succeed.
+        Assert.Contains("gateway-protocol=", text);
    }

    /// <summary>
-    ///     Verifies that batch mode continues after a command failure and writes the error JSON
-    ///     to stdout (not stderr), followed by the EOR sentinel.
+    /// Client.Dotnet-018: the README CLI examples for the alarm subcommands at
+    /// `clients/dotnet/README.md` must drive cleanly through the production
+    /// CLI argument parser. The previous text used non-existent flags
+    /// (`--session-id`, `--max-messages`, `--alarm-reference`) that would
+    /// fail with "Unknown command" / "Missing required option --reference".
+    /// Each documented example is extracted from the README, parsed via the
+    /// production <see cref="MxGatewayClientCli.RunAsync"/>, and asserted
+    /// against exit code 0.
    /// </summary>
-    [Fact]
-    public async Task RunAsync_Batch_CommandFailure_WritesErrorJsonToStdoutAndContinues()
+    /// <param name="command">The alarm subcommand to validate (e.g. "stream-alarms", "acknowledge-alarm").</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Theory]
+    [InlineData("stream-alarms")]
+    [InlineData("acknowledge-alarm")]
+    public async Task RunAsync_ReadmeExamples_ForAlarmCommands_ParseSuccessfully(string command)
+    {
+        string readme = LocateClientReadme();
+        string[] commandLine = ExtractReadmeCommandLine(readme, command);
+        // The documented examples do not include --api-key (the README assumes
+        // the env var path documented elsewhere). Inject an API key via the
+        // standard env var so CreateOptions succeeds and the parser fully
+        // exercises the documented flag shape.
+        string? previousKey = Environment.GetEnvironmentVariable("MXGATEWAY_API_KEY");
+        Environment.SetEnvironmentVariable("MXGATEWAY_API_KEY", "test-api-key");
+
+        try
        {
            using var output = new StringWriter();
            using var error = new StringWriter();
-        // First line: a gateway command with no API key (will fail).
-        // Second line: version (will succeed).
-        using var stdin = new StringReader("open-session --endpoint http://localhost:5000\nversion --json\n");
+            FakeCliClient fakeClient = new();
+            fakeClient.AlarmFeedMessages.Add(new AlarmFeedMessage
+            {
+                ActiveAlarm = new ActiveAlarmSnapshot { AlarmFullReference = "fixture" },
+            });
+            fakeClient.AcknowledgeAlarmReplies.Enqueue(new AcknowledgeAlarmReply
+            {
+                CorrelationId = "ack-fixture",
+                ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
+            });

            int exitCode = await MxGatewayClientCli.RunAsync(
-            ["batch"],
+                commandLine,
                output,
                error,
-            clientFactory: _ => throw new InvalidOperationException("injected failure"),
-            standardInput: stdin);
+                _ => fakeClient);

-        Assert.Equal(0, exitCode);
-        string text = output.ToString();
-
-        // Error record: the error JSON must be on stdout, not stderr.
-        Assert.Contains("\"error\"", text);
-        Assert.Equal(string.Empty, error.ToString());
-
-        // Both records must be present.
-        int firstEor = text.IndexOf("__MXGW_BATCH_EOR__", StringComparison.Ordinal);
-        int secondEor = text.IndexOf("__MXGW_BATCH_EOR__", firstEor + 1, StringComparison.Ordinal);
-        Assert.True(firstEor >= 0, "EOR after failed command must be present.");
-        Assert.True(secondEor > firstEor, "EOR after successful command must follow first EOR.");
-
-        // Second record must contain the version output.
-        string afterFirstEor = text[(firstEor + "__MXGW_BATCH_EOR__".Length)..];
-        Assert.Contains("\"gatewayProtocolVersion\"", afterFirstEor);
+            Assert.True(
+                exitCode == 0,
+                $"README example for '{command}' exited {exitCode}; stderr=<<{error}>>");
+            Assert.DoesNotContain("Unknown command", error.ToString());
+            Assert.DoesNotContain("Missing required option", error.ToString());
+        }
+        finally
+        {
+            Environment.SetEnvironmentVariable("MXGATEWAY_API_KEY", previousKey);
+        }
    }

-    /// <summary>Verifies that batch mode treats an empty (blank) line as EOF and exits 0.</summary>
+    /// <summary>
+    /// Client.Dotnet-019: `BenchReadBulkAsync` previously fell back to
+    /// <c>reply.ReturnValue.Int32Value</c> when the register reply had no
+    /// typed <c>Register</c> payload, silently driving the rest of the bench
+    /// against a zero server handle. The fix must fail loudly with a
+    /// descriptive <see cref="MxGatewayException"/>.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
-    public async Task RunAsync_Batch_EmptyLine_ExitsZeroAfterPreviousCommands()
+    public async Task RunAsync_BenchReadBulk_WhenRegisterReplyMissingTypedPayload_FailsLoudly()
    {
        using var output = new StringWriter();
        using var error = new StringWriter();
-        // One command, then an empty line (stop signal), then another command that must NOT run.
-        using var stdin = new StringReader("version --json\n\nversion --json\n");
+        FakeCliClient fakeClient = new();
+        // Successful protocol + MX status but no typed `Register` payload.
+        // Before the Client.Dotnet-019 fix this silently became serverHandle=0
+        // and the bench proceeded through SubscribeBulk / warmup / steady-state
+        // against an invalid handle, producing a misleading zero-result summary.
+        fakeClient.InvokeReplies.Enqueue(new MxCommandReply
+        {
+            SessionId = "session-fixture",
+            Kind = MxCommandKind.Register,
+            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
+        });

        int exitCode = await MxGatewayClientCli.RunAsync(
-            ["batch"],
+            [
+                "bench-read-bulk",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--duration-seconds",
+                "1",
+                "--warmup-seconds",
+                "0",
+                "--bulk-size",
+                "1",
+            ],
            output,
            error,
-            clientFactory: null,
-            standardInput: stdin);
+            _ => fakeClient);

-        Assert.Equal(0, exitCode);
-        string text = output.ToString();
-        // Only one EOR sentinel — the second command after the empty line must not execute.
-        int firstEor = text.IndexOf("__MXGW_BATCH_EOR__", StringComparison.Ordinal);
-        int secondEor = text.IndexOf("__MXGW_BATCH_EOR__", firstEor + 1, StringComparison.Ordinal);
-        Assert.True(firstEor >= 0, "One EOR sentinel must be present.");
-        Assert.Equal(-1, secondEor);
-        Assert.Equal(string.Empty, error.ToString());
+        Assert.Equal(1, exitCode);
+        // Descriptive message that names the missing typed payload.
+        string err = error.ToString();
+        Assert.Contains("Register", err);
+        // The bench must not produce any aggregate stats JSON.
+        Assert.DoesNotContain("bench-read-bulk", output.ToString());
+    }
+
+    /// <summary>
+    /// Client.Dotnet-020: the steady-state loop in `BenchReadBulkAsync` had a
+    /// bare `catch { failedCalls++; continue; }` that swallowed
+    /// <see cref="OperationCanceledException"/>, so token-driven cancellation
+    /// kept spinning until <c>--duration-seconds</c> elapsed. After the fix
+    /// the bench must exit promptly when the supplied token cancels.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task RunAsync_BenchReadBulk_WhenSteadyStateLoopReceivesCancellation_ExitsPromptly()
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+
+        int invokeCount = 0;
+        FakeCliClient fakeClient = new()
+        {
+            InvokeHandler = (request, ct) =>
+            {
+                int n = Interlocked.Increment(ref invokeCount);
+
+                // Reply 1 = Register (success with typed payload).
+                if (request.Command.Kind == MxCommandKind.Register)
+                {
+                    return Task.FromResult(new MxCommandReply
+                    {
+                        SessionId = "session-fixture",
+                        Kind = MxCommandKind.Register,
+                        ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
+                        Register = new RegisterReply { ServerHandle = 1 },
+                    });
+                }
+
+                // Reply 2 = SubscribeBulk (success).
+                if (request.Command.Kind == MxCommandKind.SubscribeBulk)
+                {
+                    var subscribeReply = new MxCommandReply
+                    {
+                        SessionId = "session-fixture",
+                        Kind = MxCommandKind.SubscribeBulk,
+                        ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
+                        SubscribeBulk = new BulkSubscribeReply(),
+                    };
+                    return Task.FromResult(subscribeReply);
+                }
+
+                // ReadBulk reply 1 = success (so the steady-state loop enters
+                // and starts iterating). Reply 2+ = simulated cancellation.
+                if (request.Command.Kind == MxCommandKind.ReadBulk && n <= 3)
+                {
+                    return Task.FromResult(new MxCommandReply
+                    {
+                        SessionId = "session-fixture",
+                        Kind = MxCommandKind.ReadBulk,
+                        ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
+                        ReadBulk = new BulkReadReply(),
+                    });
+                }
+
+                // From here on every ReadBulk throws OCE — the steady-state
+                // loop must exit promptly rather than spinning until
+                // --duration-seconds elapses.
+                throw new OperationCanceledException();
+            },
+        };
+
+        var sw = System.Diagnostics.Stopwatch.StartNew();
+        await Assert.ThrowsAsync<OperationCanceledException>(async () =>
+            await MxGatewayClientCli.RunAsync(
+                [
+                    "bench-read-bulk",
+                    "--endpoint",
+                    "http://localhost:5000",
+                    "--api-key",
+                    "test-api-key",
+                    "--duration-seconds",
+                    "30",
+                    "--warmup-seconds",
+                    "0",
+                    "--bulk-size",
+                    "1",
+                ],
+                output,
+                error,
+                _ => fakeClient));
+        sw.Stop();
+
+        // Without the fix the loop swallows OCE and continues until the 30 s
+        // steady-state deadline expires. With the fix it exits as soon as OCE
+        // surfaces. Generous 10 s ceiling to keep the test stable under load.
+        Assert.True(
+            sw.Elapsed < TimeSpan.FromSeconds(10),
+            $"Bench did not exit promptly on cancellation; took {sw.Elapsed}.");
+    }
+
+    /// <summary>
+    /// Client.Dotnet-021: both `ReadBulkAsync` and `BenchReadBulkAsync` cast
+    /// the user-supplied <c>--timeout-ms</c> to <see cref="uint"/> without
+    /// bounds checking, so a negative value (e.g. <c>-1</c>) silently wraps
+    /// to ~49.7 days. The fix must reject negatives with a clear error.
+    /// </summary>
+    /// <param name="command">The bulk-read subcommand to validate (e.g. "read-bulk", "bench-read-bulk").</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Theory]
+    [InlineData("read-bulk")]
+    [InlineData("bench-read-bulk")]
+    public async Task RunAsync_TimeoutMs_NegativeValue_RejectsWithClearError(string command)
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+        FakeCliClient fakeClient = new();
+
+        string[] args = command is "read-bulk"
+            ? [
+                "read-bulk",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--session-id",
+                "session-fixture",
+                "--server-handle",
+                "1",
+                "--items",
+                "Area001.Pump001.Speed",
+                "--timeout-ms",
+                "-1",
+            ]
+            : [
+                "bench-read-bulk",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--duration-seconds",
+                "1",
+                "--warmup-seconds",
+                "0",
+                "--bulk-size",
+                "1",
+                "--timeout-ms",
+                "-1",
+            ];
+
+        int exitCode = await MxGatewayClientCli.RunAsync(
+            args,
+            output,
+            error,
+            _ => fakeClient);
+
+        Assert.NotEqual(0, exitCode);
+        string err = error.ToString();
+        Assert.Contains("timeout-ms", err);
+        Assert.Contains("non-negative", err);
+    }
+
+    /// <summary>
+    /// Locates the .NET client README by walking up from the test assembly's
+    /// base directory until <c>clients/dotnet/README.md</c> is found. Keeps
+    /// the regression test independent of the current working directory.
+    /// </summary>
+    private static string LocateClientReadme()
+    {
+        string? directory = AppContext.BaseDirectory;
+        while (!string.IsNullOrEmpty(directory))
+        {
+            string candidate = Path.Combine(directory, "clients", "dotnet", "README.md");
+            if (File.Exists(candidate))
+            {
+                return candidate;
+            }
+
+            directory = Path.GetDirectoryName(directory);
+        }
+
+        throw new FileNotFoundException("clients/dotnet/README.md not found above test assembly base directory.");
+    }
+
+    /// <summary>
+    /// Extracts the documented CLI invocation for the requested subcommand
+    /// from the README, returning only the arguments after the
+    /// <c>mxgw-dotnet</c>-equivalent prefix so they can be passed straight
+    /// to <see cref="MxGatewayClientCli.RunAsync"/>.
+    /// </summary>
+    private static string[] ExtractReadmeCommandLine(string readmePath, string command)
+    {
+        string[] lines = File.ReadAllLines(readmePath);
+        // Look for the documented `dotnet run ... -- <command> ...` line.
+        foreach (string line in lines)
+        {
+            int dashes = line.IndexOf("-- " + command, StringComparison.Ordinal);
+            if (dashes < 0)
+            {
+                continue;
+            }
+
+            string after = line[(dashes + 3)..].Trim();
+            // Tokenize by whitespace, respecting "..." quoted segments.
+            return TokenizeCommandLine(after);
+        }
+
+        throw new InvalidOperationException(
+            $"README at '{readmePath}' has no documented example for subcommand '{command}'.");
+    }
+
+    /// <summary>
+    /// Splits a single command-line string into argv tokens, honouring
+    /// double-quoted segments so paths with embedded spaces survive intact.
+    /// </summary>
+    private static string[] TokenizeCommandLine(string input)
+    {
+        var tokens = new List<string>();
+        var current = new System.Text.StringBuilder();
+        bool inQuotes = false;
+
+        foreach (char ch in input)
+        {
+            if (ch == '"')
+            {
+                inQuotes = !inQuotes;
+                continue;
+            }
+
+            if (!inQuotes && char.IsWhiteSpace(ch))
+            {
+                if (current.Length > 0)
+                {
+                    tokens.Add(current.ToString());
+                    current.Clear();
+                }
+                continue;
+            }
+
+            current.Append(ch);
+        }
+
+        if (current.Length > 0)
+        {
+            tokens.Add(current.ToString());
+        }
+
+        return tokens.ToArray();
    }

    /// <summary>Fake CLI client for testing.</summary>
@@ -702,15 +894,11 @@ public sealed class MxGatewayClientCliTests
        /// <summary>Exception to throw on invoke, if any.</summary>
        public Exception? InvokeFailure { get; init; }

-        /// <summary>
-        ///     When set, after yielding all <see cref="Events"/> the stream
-        ///     awaits the provided handle and then throws
-        ///     <see cref="OperationCanceledException"/> — used to simulate the
-        ///     CLI timeout / Ctrl+C cancellation path (Client.Dotnet-017).
-        /// </summary>
-        public Func<CancellationToken, Task>? StreamHangAfterEvents { get; set; }
+        /// <summary>Optional per-call handler that overrides queue-based behaviour.</summary>
+        public Func<MxCommandRequest, CancellationToken, Task<MxCommandReply>>? InvokeHandler { get; init; }

-        /// <inheritdoc />
+        /// <summary>Releases resources held by the fake CLI client.</summary>
+        /// <returns>A completed value task.</returns>
        public ValueTask DisposeAsync()
        {
            return ValueTask.CompletedTask;
@@ -755,6 +943,11 @@ public sealed class MxGatewayClientCliTests
                throw InvokeFailure;
            }

+            if (InvokeHandler is not null)
+            {
+                return InvokeHandler(request, cancellationToken);
+            }
+
            return Task.FromResult(InvokeReplies.Dequeue());
        }

@@ -769,11 +962,6 @@ public sealed class MxGatewayClientCliTests
                await Task.Yield();
                yield return gatewayEvent;
            }
-
-            if (StreamHangAfterEvents is not null)
-            {
-                await StreamHangAfterEvents(cancellationToken).ConfigureAwait(false);
-            }
        }

        /// <summary>Queue of acknowledge-alarm replies to return.</summary>
@@ -820,6 +1008,7 @@ public sealed class MxGatewayClientCliTests
        /// <summary>Galaxy discover hierarchy reply to return.</summary>
        public DiscoverHierarchyReply GalaxyDiscoverHierarchyReply { get; set; } = new();

+        /// <summary>Queue of galaxy discover hierarchy replies to return.</summary>
        public Queue<DiscoverHierarchyReply> GalaxyDiscoverHierarchyReplies { get; } = new();

        /// <summary>List of received galaxy test connection requests.</summary>
@@ -1,6 +1,6 @@
-using MxGateway.Contracts;
+using ZB.MOM.WW.MxGateway.Contracts;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxGatewayClientContractInfoTests
 {
@@ -1,4 +1,4 @@
-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxGatewayClientOptionsTests
 {
@@ -1,12 +1,13 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
 using Grpc.Core;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 /// <summary>Tests for MxGatewaySession and client command behavior.</summary>
 public sealed class MxGatewayClientSessionTests
 {
    /// <summary>Verifies that open session attaches API key metadata and cancellation token.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task OpenSessionRawAsync_AttachesApiKeyMetadataAndCancellation()
    {
@@ -22,6 +23,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that open session returns a session with the raw open reply.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task OpenSessionAsync_ReturnsSessionWithRawOpenReply()
    {
@@ -37,6 +39,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that register builds a register command and returns server handle.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task RegisterAsync_BuildsRegisterCommandAndReturnsServerHandle()
    {
@@ -62,6 +65,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that add item 2 builds a command with the specified context.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task AddItem2Async_BuildsAddItem2CommandWithContext()
    {
@@ -87,6 +91,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that write raw builds a write command with the raw value.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task WriteRawAsync_BuildsWriteCommandWithRawValue()
    {
@@ -118,6 +123,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that write 2 raw builds a write 2 command with value and timestamp.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task Write2RawAsync_BuildsWrite2CommandWithValueAndTimestamp()
    {
@@ -146,6 +152,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that subscribe bulk builds one command and returns per-item results.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task SubscribeBulkAsync_BuildsOneBulkCommandAndReturnsPerItemResults()
    {
@@ -184,97 +191,8 @@ public sealed class MxGatewayClientSessionTests
        Assert.Equal(["Area001.Pump001.Speed"], request.Command.SubscribeBulk.TagAddresses);
    }

-    /// <summary>
-    /// Verifies that WriteBulk builds one command carrying the entry list verbatim
-    /// and returns the per-entry BulkWriteResult list without throwing on per-entry
-    /// failures.
-    /// </summary>
-    [Fact]
-    public async Task WriteBulkAsync_BuildsOneBulkCommandAndReturnsPerEntryResults()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.WriteBulk,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-            WriteBulk = new BulkWriteReply
-            {
-                Results =
-                {
-                    new BulkWriteResult { ServerHandle = 12, ItemHandle = 901, WasSuccessful = true },
-                    new BulkWriteResult { ServerHandle = 12, ItemHandle = 902, WasSuccessful = false, ErrorMessage = "Invalid handle" },
-                },
-            },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        IReadOnlyList<BulkWriteResult> results = await session.WriteBulkAsync(
-            12,
-            new[]
-            {
-                new WriteBulkEntry { ItemHandle = 901, UserId = 5, Value = new MxValue { DataType = MxDataType.Integer, Int32Value = 11 } },
-                new WriteBulkEntry { ItemHandle = 902, UserId = 5, Value = new MxValue { DataType = MxDataType.Integer, Int32Value = 22 } },
-            });
-
-        Assert.Equal(2, results.Count);
-        Assert.True(results[0].WasSuccessful);
-        Assert.False(results[1].WasSuccessful);
-        MxCommandRequest request = Assert.Single(transport.InvokeCalls).Request;
-        Assert.Equal(MxCommandKind.WriteBulk, request.Command.Kind);
-        Assert.Equal(12, request.Command.WriteBulk.ServerHandle);
-        Assert.Equal(2, request.Command.WriteBulk.Entries.Count);
-        Assert.Equal(901, request.Command.WriteBulk.Entries[0].ItemHandle);
-    }
-
-    /// <summary>
-    /// Verifies that ReadBulk forwards the timeout to the gateway as milliseconds
-    /// and unpacks the BulkReadReply payload's was_cached / value fields.
-    /// </summary>
-    [Fact]
-    public async Task ReadBulkAsync_ForwardsTimeoutAndUnpacksCachedFlag()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.ReadBulk,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-            ReadBulk = new BulkReadReply
-            {
-                Results =
-                {
-                    new BulkReadResult
-                    {
-                        ServerHandle = 12,
-                        TagAddress = "Area001.Pump001.Speed",
-                        ItemHandle = 901,
-                        WasSuccessful = true,
-                        WasCached = true,
-                        Value = new MxValue { DataType = MxDataType.Integer, Int32Value = 99 },
-                    },
-                },
-            },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        IReadOnlyList<BulkReadResult> results = await session.ReadBulkAsync(
-            12,
-            ["Area001.Pump001.Speed"],
-            TimeSpan.FromMilliseconds(750));
-
-        BulkReadResult result = Assert.Single(results);
-        Assert.True(result.WasCached);
-        Assert.Equal(99, result.Value.Int32Value);
-        MxCommandRequest request = Assert.Single(transport.InvokeCalls).Request;
-        Assert.Equal(MxCommandKind.ReadBulk, request.Command.Kind);
-        Assert.Equal(750u, request.Command.ReadBulk.TimeoutMs);
-        Assert.Equal(["Area001.Pump001.Speed"], request.Command.ReadBulk.TagAddresses);
-    }
-
    /// <summary>Verifies that stream events yields events in the order received from the gateway.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task StreamEventsAsync_YieldsEventsInGatewayOrder()
    {
@@ -306,6 +224,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that close is explicit and idempotent.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task CloseAsync_IsExplicitAndIdempotent()
    {
@@ -321,53 +240,8 @@ public sealed class MxGatewayClientSessionTests
        Assert.Equal("session-fixture", call.Request.SessionId);
    }

-    /// <summary>
-    /// Verifies that disposing a session while other callers are concurrently inside
-    /// <see cref="MxGatewaySession.CloseAsync"/> — one holding the close lock and one
-    /// parked on it — never throws <see cref="ObjectDisposedException"/> into those
-    /// callers. The close lock must outlive every pending close.
-    /// </summary>
-    [Fact]
-    public async Task DisposeAsync_DoesNotRaceConcurrentCloseAsync()
-    {
-        for (int iteration = 0; iteration < 100; iteration++)
-        {
-            FakeGatewayTransport transport = CreateTransport();
-            using SemaphoreSlim firstCloseEntered = new(0, 1);
-            using SemaphoreSlim releaseFirstClose = new(0, 1);
-
-            // The first CloseAsync to reach the transport parks here while holding the
-            // session's close lock; later callers queue on the lock behind it.
-            transport.CloseSessionHook = async () =>
-            {
-                firstCloseEntered.Release();
-                await releaseFirstClose.WaitAsync().ConfigureAwait(false);
-                transport.CloseSessionHook = null;
-            };
-
-            await using MxGatewayClient client = CreateClient(transport);
-            MxGatewaySession session = await client.OpenSessionAsync();
-
-            // Holder enters CloseAsync, acquires the lock, and parks in the hook.
-            Task holder = Task.Run(() => session.CloseAsync());
-            await firstCloseEntered.WaitAsync();
-
-            // Waiter is parked on the close lock behind the holder.
-            Task waiter = Task.Run(() => session.CloseAsync());
-
-            // DisposeAsync runs concurrently; it must wait out both callers before
-            // disposing the close lock rather than tearing it down underneath them.
-            Task dispose = session.DisposeAsync().AsTask();
-
-            releaseFirstClose.Release();
-
-            await holder;
-            await waiter;
-            await dispose;
-        }
-    }
-
    /// <summary>Verifies that invoke retries safe diagnostic commands on transient RPC failure.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task InvokeAsync_RetriesSafeDiagnosticCommandOnTransientGrpcFailure()
    {
@@ -391,36 +265,8 @@ public sealed class MxGatewayClientSessionTests
        Assert.Equal(2, transport.InvokeCalls.Count);
    }

-    /// <summary>
-    /// Verifies that the retry pipeline still retries when the transport maps the raw
-    /// <see cref="RpcException"/> to an <see cref="MxGatewayException"/> before it reaches
-    /// the retry predicate — the wrapped-exception shape that production always produces.
-    /// </summary>
-    [Fact]
-    public async Task InvokeAsync_RetriesSafeDiagnosticCommand_WhenTransportMapsRpcException()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.MapTransportExceptions = true;
-        transport.InvokeExceptions.Enqueue(CreateTransientRpcException());
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.Ping,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        await session.InvokeAsync(new MxCommandRequest
-        {
-            SessionId = session.SessionId,
-            Command = new MxCommand { Kind = MxCommandKind.Ping, Ping = new PingCommand() },
-        });
-
-        Assert.Equal(2, transport.InvokeCalls.Count);
-    }
-
    /// <summary>Verifies that open session does not retry on transient RPC failure.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task OpenSessionAsync_DoesNotRetryTransientGrpcFailure()
    {
@@ -434,6 +280,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that invoke does not retry write commands on transient RPC failure.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task InvokeAsync_DoesNotRetryWriteCommand()
    {
@@ -449,6 +296,7 @@ public sealed class MxGatewayClientSessionTests
    }

    /// <summary>Verifies that invoke helpers pass cancellation token to the transport.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task InvokeHelpers_PassCancellationTokenToTransport()
    {
@@ -468,84 +316,6 @@ public sealed class MxGatewayClientSessionTests
        Assert.Equal(cancellation.Token, Assert.Single(transport.InvokeCalls).CallOptions.CancellationToken);
    }

-    /// <summary>
-    /// Verifies that a client-imposed <see cref="StatusCode.DeadlineExceeded"/> is not
-    /// retried. The deadline budget is shared across the whole safe-unary operation, so
-    /// an immediate retry would only fail again — the call must surface the failure.
-    /// </summary>
-    [Fact]
-    public async Task InvokeAsync_DoesNotRetrySafeDiagnosticCommand_OnDeadlineExceeded()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.InvokeExceptions.Enqueue(
-            new RpcException(new Status(StatusCode.DeadlineExceeded, "deadline exceeded")));
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.Ping,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        await Assert.ThrowsAsync<RpcException>(async () => await session.InvokeAsync(
-            new MxCommandRequest
-            {
-                SessionId = session.SessionId,
-                Command = new MxCommand { Kind = MxCommandKind.Ping, Ping = new PingCommand() },
-            }));
-
-        Assert.Single(transport.InvokeCalls);
-    }
-
-    /// <summary>
-    /// Verifies that a successful register reply missing the typed <c>register</c>
-    /// payload throws a descriptive <see cref="MxGatewayException"/> rather than
-    /// silently returning a zero server handle.
-    /// </summary>
-    [Fact]
-    public async Task RegisterAsync_Throws_WhenSuccessfulReplyMissingPayload()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.Register,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        MxGatewayException exception = await Assert.ThrowsAsync<MxGatewayException>(
-            async () => await session.RegisterAsync("client-name"));
-
-        Assert.Contains("register", exception.Message, StringComparison.Ordinal);
-    }
-
-    /// <summary>
-    /// Verifies that a successful add-item reply missing the typed <c>add_item</c>
-    /// payload throws a descriptive <see cref="MxGatewayException"/> rather than
-    /// silently returning a zero item handle.
-    /// </summary>
-    [Fact]
-    public async Task AddItemAsync_Throws_WhenSuccessfulReplyMissingPayload()
-    {
-        FakeGatewayTransport transport = CreateTransport();
-        transport.AddInvokeReply(new MxCommandReply
-        {
-            SessionId = "session-fixture",
-            Kind = MxCommandKind.AddItem,
-            ProtocolStatus = new ProtocolStatus { Code = ProtocolStatusCode.Ok },
-        });
-        await using MxGatewayClient client = CreateClient(transport);
-        MxGatewaySession session = await client.OpenSessionAsync();
-
-        MxGatewayException exception = await Assert.ThrowsAsync<MxGatewayException>(
-            async () => await session.AddItemAsync(1, "Area.Pump.Speed"));
-
-        Assert.Contains("add_item", exception.Message, StringComparison.Ordinal);
-    }
-
    private static MxGatewayClient CreateClient(FakeGatewayTransport transport)
    {
        return new MxGatewayClient(transport.Options, transport);
@@ -0,0 +1,85 @@
+using System.Net.Http;
+using System.Net.Security;
+using ZB.MOM.WW.MxGateway.Client;
+
+namespace ZB.MOM.WW.MxGateway.Client.Tests;
+
+public sealed class MxGatewayClientTlsHandlerTests
+{
+    /// <summary>
+    /// Verifies that when TLS is used with no pinned CA and RequireCertificateValidation is false (default),
+    /// the handler installs an accept-all callback so the gateway's self-signed cert is trusted.
+    /// The callback must return true regardless of chain errors.
+    /// </summary>
+    [Fact]
+    public void Handler_SkipsVerification_WhenTlsAndNoCaPinned()
+    {
+        MxGatewayClientOptions options = new()
+        {
+            Endpoint = new Uri("https://localhost:5120"),
+            ApiKey = "k",
+            UseTls = true,
+        };
+        using SocketsHttpHandler handler = MxGatewayClient.CreateHttpHandlerForTests(options);
+        Assert.NotNull(handler.SslOptions.RemoteCertificateValidationCallback);
+        Assert.True(handler.SslOptions.RemoteCertificateValidationCallback!(null!, null!, null, SslPolicyErrors.RemoteCertificateChainErrors));
+    }
+
+    /// <summary>
+    /// Verifies that when RequireCertificateValidation is true, the callback is left null
+    /// so the OS trust store performs validation.
+    /// </summary>
+    [Fact]
+    public void Handler_KeepsDefaultVerification_WhenRequireCertificateValidation()
+    {
+        MxGatewayClientOptions options = new()
+        {
+            Endpoint = new Uri("https://localhost:5120"),
+            ApiKey = "k",
+            UseTls = true,
+            RequireCertificateValidation = true,
+        };
+        using SocketsHttpHandler handler = MxGatewayClient.CreateHttpHandlerForTests(options);
+        Assert.Null(handler.SslOptions.RemoteCertificateValidationCallback);
+    }
+}
+
+public sealed class GalaxyRepositoryClientTlsHandlerTests
+{
+    /// <summary>
+    /// Verifies that when TLS is used with no pinned CA and RequireCertificateValidation is false (default),
+    /// the Galaxy client handler installs an accept-all callback so the gateway's self-signed cert is trusted.
+    /// The callback must return true regardless of chain errors.
+    /// </summary>
+    [Fact]
+    public void Handler_SkipsVerification_WhenTlsAndNoCaPinned()
+    {
+        MxGatewayClientOptions options = new()
+        {
+            Endpoint = new Uri("https://localhost:5120"),
+            ApiKey = "k",
+            UseTls = true,
+        };
+        using SocketsHttpHandler handler = GalaxyRepositoryClient.CreateHttpHandlerForTests(options);
+        Assert.NotNull(handler.SslOptions.RemoteCertificateValidationCallback);
+        Assert.True(handler.SslOptions.RemoteCertificateValidationCallback!(null!, null!, null, SslPolicyErrors.RemoteCertificateChainErrors));
+    }
+
+    /// <summary>
+    /// Verifies that when RequireCertificateValidation is true, the Galaxy client callback is left null
+    /// so the OS trust store performs validation.
+    /// </summary>
+    [Fact]
+    public void Handler_KeepsDefaultVerification_WhenRequireCertificateValidation()
+    {
+        MxGatewayClientOptions options = new()
+        {
+            Endpoint = new Uri("https://localhost:5120"),
+            ApiKey = "k",
+            UseTls = true,
+            RequireCertificateValidation = true,
+        };
+        using SocketsHttpHandler handler = GalaxyRepositoryClient.CreateHttpHandlerForTests(options);
+        Assert.Null(handler.SslOptions.RemoteCertificateValidationCallback);
+    }
+}
@@ -1,8 +1,9 @@
-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxGatewayGeneratedContractTests
 {
    /// <summary>Verifies that the generated gRPC client can be instantiated from the client factory.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task GeneratedGrpcClient_CanBeConstructedFromClientFactory()
    {
@@ -1,9 +1,9 @@
 using System.Text.Json;
 using Google.Protobuf;
-using MxGateway.Client;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxStatusProxyExtensionsTests
 {
@@ -1,9 +1,9 @@
 using System.Text.Json;
 using Google.Protobuf;
-using MxGateway.Client;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Client;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client.Tests;
+namespace ZB.MOM.WW.MxGateway.Client.Tests;

 public sealed class MxValueExtensionsTests
 {
@@ -19,8 +19,8 @@
  </ItemGroup>

  <ItemGroup>
-    <ProjectReference Include="..\MxGateway.Client\MxGateway.Client.csproj" />
-    <ProjectReference Include="..\MxGateway.Client.Cli\MxGateway.Client.Cli.csproj" />
+    <ProjectReference Include="..\ZB.MOM.WW.MxGateway.Client\ZB.MOM.WW.MxGateway.Client.csproj" />
+    <ProjectReference Include="..\ZB.MOM.WW.MxGateway.Client.Cli\ZB.MOM.WW.MxGateway.Client.Cli.csproj" />
  </ItemGroup>

 </Project>
@@ -0,0 +1,11 @@
+<Solution>
+  <Configurations>
+    <Platform Name="Any CPU" />
+    <Platform Name="x64" />
+    <Platform Name="x86" />
+  </Configurations>
+  <Project Path="../../src/ZB.MOM.WW.MxGateway.Contracts/ZB.MOM.WW.MxGateway.Contracts.csproj" />
+  <Project Path="ZB.MOM.WW.MxGateway.Client.Cli/ZB.MOM.WW.MxGateway.Client.Cli.csproj" />
+  <Project Path="ZB.MOM.WW.MxGateway.Client.Tests/ZB.MOM.WW.MxGateway.Client.Tests.csproj" />
+  <Project Path="ZB.MOM.WW.MxGateway.Client/ZB.MOM.WW.MxGateway.Client.csproj" />
+</Solution>
@@ -0,0 +1,26 @@
+namespace ZB.MOM.WW.MxGateway.Client;
+
+/// <summary>
+///     Filters and shape options for <see cref="GalaxyRepositoryClient.BrowseAsync(BrowseChildrenOptions, System.Threading.CancellationToken)"/>.
+///     Mirror of <see cref="DiscoverHierarchyOptions"/> for the lazy-browse path.
+/// </summary>
+public sealed class BrowseChildrenOptions
+{
+    /// <summary>Restrict to children whose Galaxy category is in this set.</summary>
+    public IReadOnlyList<int> CategoryIds { get; init; } = [];
+
+    /// <summary>Restrict to children whose template chain contains any of these tokens.</summary>
+    public IReadOnlyList<string> TemplateChainContains { get; init; } = [];
+
+    /// <summary>Optional glob-style filter on <c>tag_name</c>.</summary>
+    public string? TagNameGlob { get; init; }
+
+    /// <summary>Whether to populate each <c>GalaxyObject.Attributes</c>. Null leaves the server default.</summary>
+    public bool? IncludeAttributes { get; init; }
+
+    /// <summary>Restrict to children that bear at least one alarm attribute.</summary>
+    public bool AlarmBearingOnly { get; init; }
+
+    /// <summary>Restrict to children that have at least one historized attribute.</summary>
+    public bool HistorizedOnly { get; init; }
+}
@@ -0,0 +1,43 @@
+namespace ZB.MOM.WW.MxGateway.Client;
+
+/// <summary>
+/// Filters and shape options for <see cref="GalaxyRepositoryClient.DiscoverHierarchyAsync(DiscoverHierarchyOptions, System.Threading.CancellationToken)"/>.
+/// </summary>
+/// <remarks>
+/// Hand-written ergonomic wrapper around the generated
+/// <c>DiscoverHierarchyRequest</c>: lets callers express a Galaxy-browse
+/// slice with .NET-friendly nullable scalars and collection initializers,
+/// without touching the protobuf message's <c>oneof root</c> directly.
+/// </remarks>
+public sealed class DiscoverHierarchyOptions
+{
+    /// <summary>Restrict to the subtree rooted at this Galaxy <c>gobject_id</c>.</summary>
+    public int? RootGobjectId { get; init; }
+
+    /// <summary>Restrict to the subtree rooted at the object with this tag name.</summary>
+    public string? RootTagName { get; init; }
+
+    /// <summary>Restrict to the subtree rooted at this <c>contained_name</c> path.</summary>
+    public string? RootContainedPath { get; init; }
+
+    /// <summary>Maximum traversal depth, measured from the chosen root.</summary>
+    public int? MaxDepth { get; init; }
+
+    /// <summary>Restrict to objects whose Galaxy category is in this set.</summary>
+    public IReadOnlyList<int> CategoryIds { get; init; } = [];
+
+    /// <summary>Restrict to objects whose template chain contains any of these tokens.</summary>
+    public IReadOnlyList<string> TemplateChainContains { get; init; } = [];
+
+    /// <summary>Optional glob-style filter on <c>tag_name</c>.</summary>
+    public string? TagNameGlob { get; init; }
+
+    /// <summary>Whether to populate each <c>GalaxyObject.Attributes</c>. Null leaves the server default.</summary>
+    public bool? IncludeAttributes { get; init; }
+
+    /// <summary>Restrict to objects that bear at least one alarm attribute.</summary>
+    public bool AlarmBearingOnly { get; init; }
+
+    /// <summary>Restrict to objects that have at least one historized attribute.</summary>
+    public bool HistorizedOnly { get; init; }
+}
@@ -2,14 +2,14 @@ using Google.Protobuf.WellKnownTypes;
 using Grpc.Core;
 using Grpc.Net.Client;
 using Microsoft.Extensions.Logging;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;
 using Polly;
 using System.Net.Http;
 using System.Net.Security;
 using System.Runtime.CompilerServices;
 using System.Security.Cryptography.X509Certificates;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Provides the .NET client entry point for the public Galaxy Repository gRPC API.
@@ -19,11 +19,12 @@ namespace MxGateway.Client;
 public sealed class GalaxyRepositoryClient : IAsyncDisposable
 {
    private const int DiscoverHierarchyPageSize = 5000;
+    private const int BrowseChildrenPageSize = 500;

    private readonly GrpcChannel? _channel;
    private readonly IGalaxyRepositoryClientTransport _transport;
    private readonly ResiliencePipeline _safeUnaryRetryPipeline;
-    private int _disposed;
+    private bool _disposed;

    /// <summary>
    /// Initializes a Galaxy Repository client with custom transport and options.
@@ -182,17 +183,10 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
        return await DiscoverHierarchyAsync(new DiscoverHierarchyOptions(), cancellationToken).ConfigureAwait(false);
    }

-    /// <summary>
-    /// Enumerates the deployed Galaxy object hierarchy with caller-supplied
-    /// server-side filters. Each returned <see cref="GalaxyObject"/> may include
-    /// its dynamic attributes (controlled by <see cref="DiscoverHierarchyOptions.IncludeAttributes"/>),
-    /// so callers can determine which tag references they may subscribe to via
-    /// the MxAccessGateway service. The client transparently follows the
-    /// gateway's pagination cursor until the hierarchy is fully drained.
-    /// </summary>
-    /// <param name="options">Server-side filter and shape options.</param>
-    /// <param name="cancellationToken">Cancellation token.</param>
-    /// <returns>The filtered collection of Galaxy objects.</returns>
+    /// <summary>Discovers the Galaxy object hierarchy.</summary>
+    /// <param name="options">Client configuration options.</param>
+    /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>The collection of Galaxy objects in the hierarchy.</returns>
    public async Task<IReadOnlyList<GalaxyObject>> DiscoverHierarchyAsync(
        DiscoverHierarchyOptions options,
        CancellationToken cancellationToken = default)
@@ -285,6 +279,92 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
            cancellationToken);
    }

+    /// <summary>Returns root-level browse nodes (objects with no parent).</summary>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The list of root <see cref="LazyBrowseNode"/> instances.</returns>
+    public Task<IReadOnlyList<LazyBrowseNode>> BrowseAsync(CancellationToken cancellationToken = default)
+        => BrowseAsync(null, cancellationToken);
+
+    /// <summary>Returns root-level browse nodes filtered by the given options.</summary>
+    /// <param name="options">Browse filter options. Null applies no filter.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The list of root <see cref="LazyBrowseNode"/> instances.</returns>
+    public async Task<IReadOnlyList<LazyBrowseNode>> BrowseAsync(
+        BrowseChildrenOptions? options,
+        CancellationToken cancellationToken = default)
+    {
+        BrowseChildrenOptions effective = options ?? new BrowseChildrenOptions();
+        List<LazyBrowseNode> roots = [];
+        string pageToken = string.Empty;
+        HashSet<string> seenPageTokens = new(StringComparer.Ordinal);
+        do
+        {
+            BrowseChildrenRequest request = BuildBrowseChildrenRequest(effective);
+            request.PageToken = pageToken;
+            BrowseChildrenReply reply = await BrowseChildrenRawAsync(request, cancellationToken).ConfigureAwait(false);
+
+            for (int i = 0; i < reply.Children.Count; i++)
+            {
+                bool hint = i < reply.ChildHasChildren.Count && reply.ChildHasChildren[i];
+                roots.Add(new LazyBrowseNode(this, reply.Children[i], hint, effective));
+            }
+
+            pageToken = reply.NextPageToken;
+            if (!string.IsNullOrWhiteSpace(pageToken) && !seenPageTokens.Add(pageToken))
+            {
+                throw new MxGatewayException(
+                    $"Galaxy BrowseChildren returned a repeated page token '{pageToken}'.");
+            }
+        }
+        while (!string.IsNullOrWhiteSpace(pageToken));
+
+        return roots;
+    }
+
+    /// <summary>Issues a raw BrowseChildren RPC without result wrapping.</summary>
+    /// <param name="request">The browse-children request.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The raw server reply.</returns>
+    public Task<BrowseChildrenReply> BrowseChildrenRawAsync(
+        BrowseChildrenRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return ExecuteSafeUnaryAsync(
+            token => _transport.BrowseChildrenAsync(request, CreateCallOptions(token)),
+            cancellationToken);
+    }
+
+    /// <summary>Builds a <see cref="BrowseChildrenRequest"/> from the provided options.</summary>
+    /// <param name="options">Browse children options to convert.</param>
+    /// <returns>The constructed request message.</returns>
+    internal static BrowseChildrenRequest BuildBrowseChildrenRequest(BrowseChildrenOptions options)
+    {
+        ArgumentNullException.ThrowIfNull(options);
+
+        BrowseChildrenRequest request = new()
+        {
+            PageSize = BrowseChildrenPageSize,
+            AlarmBearingOnly = options.AlarmBearingOnly,
+            HistorizedOnly = options.HistorizedOnly,
+        };
+        request.CategoryIds.Add(options.CategoryIds);
+        request.TemplateChainContains.Add(options.TemplateChainContains);
+        if (!string.IsNullOrWhiteSpace(options.TagNameGlob))
+        {
+            request.TagNameGlob = options.TagNameGlob;
+        }
+
+        if (options.IncludeAttributes.HasValue)
+        {
+            request.IncludeAttributes = options.IncludeAttributes.Value;
+        }
+
+        return request;
+    }
+
    /// <summary>
    /// Subscribes to Galaxy deploy events. The server emits a bootstrap event with the
    /// current state on subscribe so callers can prime their cache, then emits one event
@@ -347,13 +427,15 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
    /// <summary>
    /// Closes the gRPC channel and releases resources.
    /// </summary>
+    /// <returns>A task that represents the asynchronous dispose operation.</returns>
    public ValueTask DisposeAsync()
    {
-        if (Interlocked.Exchange(ref _disposed, 1) != 0)
+        if (_disposed)
        {
            return ValueTask.CompletedTask;
        }

+        _disposed = true;
        _channel?.Dispose();
        return ValueTask.CompletedTask;
    }
@@ -412,7 +494,13 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
            .ConfigureAwait(false);
    }

-    private static HttpMessageHandler CreateHttpHandler(MxGatewayClientOptions options)
+    private static HttpMessageHandler CreateHttpHandler(MxGatewayClientOptions options) =>
+        CreateHttpHandlerForTests(options);
+
+    /// <summary>Creates an <see cref="HttpMessageHandler"/> configured from the provided options for test use.</summary>
+    /// <param name="options">Client options used to configure TLS and timeouts.</param>
+    /// <returns>The configured HTTP message handler.</returns>
+    internal static SocketsHttpHandler CreateHttpHandlerForTests(MxGatewayClientOptions options)
    {
        SocketsHttpHandler handler = new()
        {
@@ -432,6 +520,11 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
                X509Certificate2 trustedRoot = X509CertificateLoader.LoadCertificateFromFile(options.CaCertificatePath);
                handler.SslOptions.RemoteCertificateValidationCallback = (_, certificate, chain, errors) =>
                {
+                    if ((errors & System.Net.Security.SslPolicyErrors.RemoteCertificateNameMismatch) != 0)
+                    {
+                        return false;
+                    }
+
                    if (certificate is null)
                    {
                        return false;
@@ -447,6 +540,10 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable
                    return customChain.Build(certificateToValidate);
                };
            }
+            else if (!options.RequireCertificateValidation)
+            {
+                handler.SslOptions.RemoteCertificateValidationCallback = (_, _, _, _) => true;
+            }
        }

        return handler;
@@ -454,6 +551,6 @@ public sealed class GalaxyRepositoryClient : IAsyncDisposable

    private void ThrowIfDisposed()
    {
-        ObjectDisposedException.ThrowIf(Volatile.Read(ref _disposed) != 0, this);
+        ObjectDisposedException.ThrowIf(_disposed, this);
    }
 }
@@ -1,7 +1,7 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// gRPC implementation of IGalaxyRepositoryClientTransport.
@@ -10,9 +10,7 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
    MxGatewayClientOptions options,
    GalaxyRepository.GalaxyRepositoryClient rawClient) : IGalaxyRepositoryClientTransport
 {
-    /// <summary>
-    /// Gets the gateway client options.
-    /// </summary>
+    /// <inheritdoc />
    public MxGatewayClientOptions Options { get; } = options;

    /// <summary>
@@ -36,7 +34,7 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

@@ -53,7 +51,7 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

@@ -70,11 +68,32 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

    /// <inheritdoc />
+    public async Task<BrowseChildrenReply> BrowseChildrenAsync(
+        BrowseChildrenRequest request,
+        CallOptions callOptions)
+    {
+        try
+        {
+            return await RawClient.BrowseChildrenAsync(request, callOptions)
+                .ResponseAsync
+                .ConfigureAwait(false);
+        }
+        catch (RpcException exception)
+        {
+            throw MapRpcException(exception, callOptions.CancellationToken);
+        }
+    }
+
+    /// <summary>Streams deploy events from the Galaxy Repository, using an explicit cancellation token that overrides the call options token when provided.</summary>
+    /// <param name="request">The watch deploy events request.</param>
+    /// <param name="callOptions">Call options for the underlying gRPC call.</param>
+    /// <param name="cancellationToken">Optional cancellation token; takes precedence over the token in <paramref name="callOptions"/> when cancellable.</param>
+    /// <returns>An async enumerable of deploy events.</returns>
    public async IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
        WatchDeployEventsRequest request,
        CallOptions callOptions,
@@ -101,7 +120,7 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
            }
            catch (RpcException exception)
            {
-                throw RpcExceptionMapper.Map(exception, effectiveCancellationToken);
+                throw MapRpcException(exception, effectiveCancellationToken);
            }

            yield return deployEvent;
@@ -115,4 +134,28 @@ internal sealed class GrpcGalaxyRepositoryClientTransport(
    {
        return WatchDeployEventsAsync(request, callOptions);
    }
+
+    private static Exception MapRpcException(
+        RpcException exception,
+        CancellationToken cancellationToken)
+    {
+        if (cancellationToken.IsCancellationRequested || exception.StatusCode == StatusCode.Cancelled)
+        {
+            return new OperationCanceledException(
+                exception.Status.Detail,
+                exception,
+                cancellationToken);
+        }
+
+        return exception.StatusCode switch
+        {
+            StatusCode.Unauthenticated => new MxGatewayAuthenticationException(
+                exception.Status.Detail,
+                innerException: exception),
+            StatusCode.PermissionDenied => new MxGatewayAuthorizationException(
+                exception.Status.Detail,
+                innerException: exception),
+            _ => new MxGatewayException(exception.Status.Detail, exception),
+        };
+    }
 }
@@ -1,7 +1,7 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// gRPC implementation of IMxGatewayClientTransport.
@@ -10,9 +10,7 @@ internal sealed class GrpcMxGatewayClientTransport(
    MxGatewayClientOptions options,
    MxAccessGateway.MxAccessGatewayClient rawClient) : IMxGatewayClientTransport
 {
-    /// <summary>
-    /// Gets the gateway client options.
-    /// </summary>
+    /// <inheritdoc />
    public MxGatewayClientOptions Options { get; } = options;

    /// <summary>
@@ -36,7 +34,7 @@ internal sealed class GrpcMxGatewayClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

@@ -53,7 +51,7 @@ internal sealed class GrpcMxGatewayClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

@@ -70,11 +68,15 @@ internal sealed class GrpcMxGatewayClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
        }
    }

-    /// <inheritdoc />
+    /// <summary>Streams MXAccess events from the gateway, forwarding an explicit cancellation token to the stream reader.</summary>
+    /// <param name="request">The stream events request.</param>
+    /// <param name="callOptions">gRPC call options.</param>
+    /// <param name="cancellationToken">Token to cancel the streaming enumeration.</param>
+    /// <returns>An async enumerable of MXAccess events.</returns>
    public async IAsyncEnumerable<MxEvent> StreamEventsAsync(
        StreamEventsRequest request,
        CallOptions callOptions,
@@ -101,7 +103,7 @@ internal sealed class GrpcMxGatewayClientTransport(
            }
            catch (RpcException exception)
            {
-                throw RpcExceptionMapper.Map(exception, effectiveCancellationToken);
+                throw MapRpcException(exception, effectiveCancellationToken);
            }

            yield return gatewayEvent;
@@ -129,11 +131,61 @@ internal sealed class GrpcMxGatewayClientTransport(
        }
        catch (RpcException exception)
        {
-            throw RpcExceptionMapper.Map(exception, callOptions.CancellationToken);
+            throw MapRpcException(exception, callOptions.CancellationToken);
+        }
+    }
+
+    /// <summary>Queries active alarms from the gateway, forwarding an explicit cancellation token to the stream reader.</summary>
+    /// <param name="request">The query active alarms request.</param>
+    /// <param name="callOptions">gRPC call options.</param>
+    /// <param name="cancellationToken">Token to cancel the streaming enumeration.</param>
+    /// <returns>An async enumerable of active alarm snapshots.</returns>
+    public async IAsyncEnumerable<ActiveAlarmSnapshot> QueryActiveAlarmsAsync(
+        QueryActiveAlarmsRequest request,
+        CallOptions callOptions,
+        [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken = default)
+    {
+        CancellationToken effectiveCancellationToken = cancellationToken.CanBeCanceled
+            ? cancellationToken
+            : callOptions.CancellationToken;
+
+        using AsyncServerStreamingCall<ActiveAlarmSnapshot> call = RawClient.QueryActiveAlarms(request, callOptions);
+
+        IAsyncStreamReader<ActiveAlarmSnapshot> responseStream = call.ResponseStream;
+        while (true)
+        {
+            ActiveAlarmSnapshot? snapshot;
+            try
+            {
+                if (!await responseStream.MoveNext(effectiveCancellationToken).ConfigureAwait(false))
+                {
+                    break;
+                }
+
+                snapshot = responseStream.Current;
+            }
+            catch (RpcException exception)
+            {
+                throw MapRpcException(exception, effectiveCancellationToken);
+            }
+
+            yield return snapshot;
        }
    }

    /// <inheritdoc />
+    IAsyncEnumerable<ActiveAlarmSnapshot> IMxGatewayClientTransport.QueryActiveAlarmsAsync(
+        QueryActiveAlarmsRequest request,
+        CallOptions callOptions)
+    {
+        return QueryActiveAlarmsAsync(request, callOptions);
+    }
+
+    /// <summary>Streams alarm feed messages from the gateway, forwarding an explicit cancellation token to the stream reader.</summary>
+    /// <param name="request">The stream alarms request.</param>
+    /// <param name="callOptions">gRPC call options.</param>
+    /// <param name="cancellationToken">Token to cancel the streaming enumeration.</param>
+    /// <returns>An async enumerable of alarm feed messages.</returns>
    public async IAsyncEnumerable<AlarmFeedMessage> StreamAlarmsAsync(
        StreamAlarmsRequest request,
        CallOptions callOptions,
@@ -160,7 +212,7 @@ internal sealed class GrpcMxGatewayClientTransport(
            }
            catch (RpcException exception)
            {
-                throw RpcExceptionMapper.Map(exception, effectiveCancellationToken);
+                throw MapRpcException(exception, effectiveCancellationToken);
            }

            yield return message;
@@ -174,4 +226,28 @@ internal sealed class GrpcMxGatewayClientTransport(
    {
        return StreamAlarmsAsync(request, callOptions);
    }
+
+    private static Exception MapRpcException(
+        RpcException exception,
+        CancellationToken cancellationToken)
+    {
+        if (cancellationToken.IsCancellationRequested || exception.StatusCode == StatusCode.Cancelled)
+        {
+            return new OperationCanceledException(
+                exception.Status.Detail,
+                exception,
+                cancellationToken);
+        }
+
+        return exception.StatusCode switch
+        {
+            StatusCode.Unauthenticated => new MxGatewayAuthenticationException(
+                exception.Status.Detail,
+                innerException: exception),
+            StatusCode.PermissionDenied => new MxGatewayAuthorizationException(
+                exception.Status.Detail,
+                innerException: exception),
+            _ => new MxGatewayException(exception.Status.Detail, exception),
+        };
+    }
 }
@@ -1,7 +1,7 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto.Galaxy;
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Transport layer for Galaxy Repository gRPC operations.</summary>
 internal interface IGalaxyRepositoryClientTransport
@@ -15,6 +15,7 @@ internal interface IGalaxyRepositoryClientTransport
    /// <summary>Tests the connection to the Galaxy Repository server.</summary>
    /// <param name="request">The test connection request.</param>
    /// <param name="callOptions">gRPC call options (timeout, cancellation, etc.).</param>
+    /// <returns>A task that resolves to the test connection reply.</returns>
    Task<TestConnectionReply> TestConnectionAsync(
        TestConnectionRequest request,
        CallOptions callOptions);
@@ -22,6 +23,7 @@ internal interface IGalaxyRepositoryClientTransport
    /// <summary>Gets the last deploy time from the Galaxy Repository server.</summary>
    /// <param name="request">The get last deploy time request.</param>
    /// <param name="callOptions">gRPC call options (timeout, cancellation, etc.).</param>
+    /// <returns>A task that resolves to the last deploy time reply.</returns>
    Task<GetLastDeployTimeReply> GetLastDeployTimeAsync(
        GetLastDeployTimeRequest request,
        CallOptions callOptions);
@@ -29,13 +31,23 @@ internal interface IGalaxyRepositoryClientTransport
    /// <summary>Discovers the object hierarchy in the Galaxy Repository.</summary>
    /// <param name="request">The discover hierarchy request.</param>
    /// <param name="callOptions">gRPC call options (timeout, cancellation, etc.).</param>
+    /// <returns>A task that resolves to the hierarchy discovery reply.</returns>
    Task<DiscoverHierarchyReply> DiscoverHierarchyAsync(
        DiscoverHierarchyRequest request,
        CallOptions callOptions);

+    /// <summary>Returns direct children of a parent in the Galaxy hierarchy.</summary>
+    /// <param name="request">The browse children request.</param>
+    /// <param name="callOptions">gRPC call options (timeout, cancellation, etc.).</param>
+    /// <returns>A task that resolves to the browse children reply.</returns>
+    Task<BrowseChildrenReply> BrowseChildrenAsync(
+        BrowseChildrenRequest request,
+        CallOptions callOptions);
+
    /// <summary>Watches for deployment events from the Galaxy Repository server.</summary>
    /// <param name="request">The watch deploy events request.</param>
    /// <param name="callOptions">gRPC call options (timeout, cancellation, etc.).</param>
+    /// <returns>An async enumerable of deploy events.</returns>
    IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
        WatchDeployEventsRequest request,
        CallOptions callOptions);
@@ -1,7 +1,7 @@
 using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 internal interface IMxGatewayClientTransport
 {
@@ -65,6 +65,17 @@ internal interface IMxGatewayClientTransport
        AcknowledgeAlarmRequest request,
        CallOptions callOptions);

+    /// <summary>
+    /// Streams a snapshot of all alarms currently in Active or ActiveAcked state — the
+    /// ConditionRefresh equivalent for the gateway.
+    /// </summary>
+    /// <param name="request">The query request, optionally scoped by alarm-reference prefix.</param>
+    /// <param name="callOptions">gRPC call options.</param>
+    /// <returns>An async enumerable of active-alarm snapshots.</returns>
+    IAsyncEnumerable<ActiveAlarmSnapshot> QueryActiveAlarmsAsync(
+        QueryActiveAlarmsRequest request,
+        CallOptions callOptions);
+
    /// <summary>
    /// Attaches to the gateway's central alarm feed — the current active-alarm
    /// snapshot followed by live transitions.
@@ -0,0 +1,107 @@
+using ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxy;
+
+namespace ZB.MOM.WW.MxGateway.Client;
+
+/// <summary>
+///     One node in a lazy-loaded Galaxy browse tree. Holds the underlying
+///     <see cref="GalaxyObject"/> and exposes <see cref="ExpandAsync"/> to fetch
+///     its direct children on demand. Expansion is one-shot: a second call is a
+///     no-op. Pagination of large sibling sets is handled internally.
+/// </summary>
+public sealed class LazyBrowseNode
+{
+    private readonly GalaxyRepositoryClient _client;
+    private readonly BrowseChildrenOptions _options;
+    private readonly List<LazyBrowseNode> _children = [];
+    private readonly SemaphoreSlim _expandLock = new(1, 1);
+    private bool _isExpanded;
+
+    /// <summary>Initializes a new instance of <see cref="LazyBrowseNode"/>.</summary>
+    /// <param name="client">The repository client used to fetch children.</param>
+    /// <param name="object">The underlying Galaxy object for this node.</param>
+    /// <param name="hasChildrenHint">True when the server reports the node has at least one matching descendant.</param>
+    /// <param name="options">Options controlling child browse behavior.</param>
+    internal LazyBrowseNode(
+        GalaxyRepositoryClient client,
+        GalaxyObject @object,
+        bool hasChildrenHint,
+        BrowseChildrenOptions options)
+    {
+        _client = client;
+        Object = @object;
+        HasChildrenHint = hasChildrenHint;
+        _options = options;
+    }
+
+    /// <summary>The underlying Galaxy object for this node.</summary>
+    public GalaxyObject Object { get; }
+
+    /// <summary>True when the server reports this node has at least one matching descendant.</summary>
+    public bool HasChildrenHint { get; }
+
+    /// <summary>Direct children loaded by <see cref="ExpandAsync"/>; empty until then.</summary>
+    public IReadOnlyList<LazyBrowseNode> Children => _children;
+
+    /// <summary>True after the first <see cref="ExpandAsync"/> call completes.</summary>
+    public bool IsExpanded => _isExpanded;
+
+    /// <summary>
+    ///     Fetches direct children from the gateway and populates <see cref="Children"/>.
+    ///     Idempotent: subsequent calls are no-ops.
+    /// </summary>
+    /// <remarks>
+    ///     Thread-safe: concurrent callers see exactly one fetch; subsequent callers
+    ///     (after the first completes) return immediately.
+    /// </remarks>
+    /// <param name="cancellationToken">Token to observe for cancellation.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    public async Task ExpandAsync(CancellationToken cancellationToken = default)
+    {
+        if (_isExpanded)
+        {
+            return;
+        }
+
+        await _expandLock.WaitAsync(cancellationToken).ConfigureAwait(false);
+        try
+        {
+            if (_isExpanded)
+            {
+                return;
+            }
+
+            string pageToken = string.Empty;
+            HashSet<string> seenPageTokens = new(StringComparer.Ordinal);
+            do
+            {
+                BrowseChildrenRequest request = GalaxyRepositoryClient.BuildBrowseChildrenRequest(_options);
+                request.ParentGobjectId = Object.GobjectId;
+                request.PageToken = pageToken;
+
+                BrowseChildrenReply reply = await _client
+                    .BrowseChildrenRawAsync(request, cancellationToken)
+                    .ConfigureAwait(false);
+
+                for (int i = 0; i < reply.Children.Count; i++)
+                {
+                    bool hint = i < reply.ChildHasChildren.Count && reply.ChildHasChildren[i];
+                    _children.Add(new LazyBrowseNode(_client, reply.Children[i], hint, _options));
+                }
+
+                pageToken = reply.NextPageToken;
+                if (!string.IsNullOrWhiteSpace(pageToken) && !seenPageTokens.Add(pageToken))
+                {
+                    throw new MxGatewayException(
+                        $"Galaxy BrowseChildren returned a repeated page token '{pageToken}'.");
+                }
+            }
+            while (!string.IsNullOrWhiteSpace(pageToken));
+
+            _isExpanded = true;
+        }
+        finally
+        {
+            _expandLock.Release();
+        }
+    }
+}
@@ -1,6 +1,6 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when an MXAccess command fails with a non-zero HResult or failing status.</summary>
 public sealed class MxAccessException : MxGatewayCommandException
@@ -1,12 +1,13 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Extension methods for checking MxCommandReply success conditions.</summary>
 public static class MxCommandReplyExtensions
 {
    /// <summary>Validates that the reply has a successful protocol status (Ok or MxAccessFailure), throwing a gateway exception if not.</summary>
    /// <param name="reply">The command reply to check.</param>
+    /// <returns>The same <paramref name="reply"/> for fluent chaining when validation passes.</returns>
    public static MxCommandReply EnsureProtocolSuccess(this MxCommandReply reply)
    {
        ArgumentNullException.ThrowIfNull(reply);
@@ -24,6 +25,7 @@ public static class MxCommandReplyExtensions

    /// <summary>Validates that the reply indicates MXAccess success (no HResult or status failures), throwing MxAccessException if not.</summary>
    /// <param name="reply">The command reply to check.</param>
+    /// <returns>The same <paramref name="reply"/> for fluent chaining when validation passes.</returns>
    public static MxCommandReply EnsureMxAccessSuccess(this MxCommandReply reply)
    {
        ArgumentNullException.ThrowIfNull(reply);
@@ -1,7 +1,6 @@
-using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when an API key is invalid, expired, or malformed.</summary>
 public sealed class MxGatewayAuthenticationException : MxGatewayException
@@ -14,7 +13,6 @@ public sealed class MxGatewayAuthenticationException : MxGatewayException
    /// <param name="hResult">The HResult code, if available.</param>
    /// <param name="statuses">The MXAccess statuses, if available.</param>
    /// <param name="innerException">The underlying exception, if any.</param>
-    /// <param name="statusCode">The gRPC status code reported by the failed call, if available.</param>
    public MxGatewayAuthenticationException(
        string message,
        string? sessionId = null,
@@ -22,8 +20,7 @@ public sealed class MxGatewayAuthenticationException : MxGatewayException
        ProtocolStatus? protocolStatus = null,
        int? hResult = null,
        IReadOnlyList<MxStatusProxy>? statuses = null,
-        Exception? innerException = null,
-        StatusCode? statusCode = null)
+        Exception? innerException = null)
        : base(
            message,
            sessionId,
@@ -31,8 +28,7 @@ public sealed class MxGatewayAuthenticationException : MxGatewayException
            protocolStatus,
            hResult,
            statuses ?? [],
-            innerException,
-            statusCode)
+            innerException)
    {
    }
 }
@@ -1,7 +1,6 @@
-using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when the API key lacks required scopes for an operation.</summary>
 public sealed class MxGatewayAuthorizationException : MxGatewayException
@@ -14,7 +13,6 @@ public sealed class MxGatewayAuthorizationException : MxGatewayException
    /// <param name="hResult">The HResult code, if available.</param>
    /// <param name="statuses">The MXAccess statuses, if available.</param>
    /// <param name="innerException">The underlying exception, if any.</param>
-    /// <param name="statusCode">The gRPC status code reported by the failed call, if available.</param>
    public MxGatewayAuthorizationException(
        string message,
        string? sessionId = null,
@@ -22,8 +20,7 @@ public sealed class MxGatewayAuthorizationException : MxGatewayException
        ProtocolStatus? protocolStatus = null,
        int? hResult = null,
        IReadOnlyList<MxStatusProxy>? statuses = null,
-        Exception? innerException = null,
-        StatusCode? statusCode = null)
+        Exception? innerException = null)
        : base(
            message,
            sessionId,
@@ -31,8 +28,7 @@ public sealed class MxGatewayAuthorizationException : MxGatewayException
            protocolStatus,
            hResult,
            statuses ?? [],
-            innerException,
-            statusCode)
+            innerException)
    {
    }
 }
@@ -1,13 +1,13 @@
 using Grpc.Core;
 using Grpc.Net.Client;
 using Microsoft.Extensions.Logging;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
 using Polly;
 using System.Net.Http;
 using System.Net.Security;
 using System.Security.Cryptography.X509Certificates;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Provides the .NET client entry point for the public MXAccess Gateway gRPC API.
@@ -17,7 +17,7 @@ public sealed class MxGatewayClient : IAsyncDisposable
    private readonly GrpcChannel _channel;
    private readonly IMxGatewayClientTransport _transport;
    private readonly ResiliencePipeline _safeUnaryRetryPipeline;
-    private int _disposed;
+    private bool _disposed;

    /// <summary>
    /// Initializes a new instance of the <see cref="MxGatewayClient"/> with given options and transport.
@@ -184,10 +184,9 @@ public sealed class MxGatewayClient : IAsyncDisposable

    /// <summary>
    /// Acknowledges an active MXAccess alarm condition through the gateway. The
-    /// gateway authorizes <see cref="AcknowledgeAlarmRequest"/> against the API
-    /// key's <c>admin</c> scope (there is no finer-grained alarm-ack sub-scope)
-    /// and forwards the acknowledge to the worker's MXAccess session; the
-    /// resulting <see cref="MxStatusProxy"/> is returned in the reply.
+    /// gateway authenticates the request against the API key's <c>invoke:alarm-ack</c>
+    /// scope and forwards the acknowledge to the worker's MXAccess session;
+    /// the resulting <see cref="MxStatusProxy"/> is returned in the reply.
    /// </summary>
    /// <param name="request">The acknowledge request — alarm reference, comment, operator user.</param>
    /// <param name="cancellationToken">Cancellation token for the operation.</param>
@@ -204,6 +203,27 @@ public sealed class MxGatewayClient : IAsyncDisposable
            cancellationToken);
    }

+    /// <summary>
+    /// Streams a snapshot of all alarms currently Active or ActiveAcked — the gateway's
+    /// ConditionRefresh equivalent. Used after reconnect to seed the local Part 9 state
+    /// machine, or to reconcile alarms that may have been missed during a transport
+    /// blip. Optionally scoped by alarm-reference prefix
+    /// (<see cref="QueryActiveAlarmsRequest.AlarmFilterPrefix"/>) so a partial refresh
+    /// can target an equipment sub-tree.
+    /// </summary>
+    /// <param name="request">The query request, optionally scoped by alarm-reference prefix.</param>
+    /// <param name="cancellationToken">Cancellation token for the stream.</param>
+    /// <returns>An async enumerable of active-alarm snapshots.</returns>
+    public IAsyncEnumerable<ActiveAlarmSnapshot> QueryActiveAlarmsAsync(
+        QueryActiveAlarmsRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return _transport.QueryActiveAlarmsAsync(request, CreateStreamCallOptions(cancellationToken));
+    }
+
    /// <summary>
    /// Attaches to the gateway's central alarm feed. The stream opens with one
    /// <see cref="AlarmFeedMessage"/> per currently-active alarm (the
@@ -229,13 +249,15 @@ public sealed class MxGatewayClient : IAsyncDisposable
    /// <summary>
    /// Disposes the client and releases all resources.
    /// </summary>
+    /// <returns>A task that represents the asynchronous dispose operation.</returns>
    public ValueTask DisposeAsync()
    {
-        if (Interlocked.Exchange(ref _disposed, 1) != 0)
+        if (_disposed)
        {
            return ValueTask.CompletedTask;
        }

+        _disposed = true;
        _channel?.Dispose();
        return ValueTask.CompletedTask;
    }
@@ -294,7 +316,13 @@ public sealed class MxGatewayClient : IAsyncDisposable
            .ConfigureAwait(false);
    }

-    private static HttpMessageHandler CreateHttpHandler(MxGatewayClientOptions options)
+    private static HttpMessageHandler CreateHttpHandler(MxGatewayClientOptions options) =>
+        CreateHttpHandlerForTests(options);
+
+    /// <summary>Creates an <see cref="HttpMessageHandler"/> configured from the provided options for test use.</summary>
+    /// <param name="options">Client options used to configure TLS and timeouts.</param>
+    /// <returns>The configured HTTP message handler.</returns>
+    internal static SocketsHttpHandler CreateHttpHandlerForTests(MxGatewayClientOptions options)
    {
        SocketsHttpHandler handler = new()
        {
@@ -314,6 +342,11 @@ public sealed class MxGatewayClient : IAsyncDisposable
                X509Certificate2 trustedRoot = X509CertificateLoader.LoadCertificateFromFile(options.CaCertificatePath);
                handler.SslOptions.RemoteCertificateValidationCallback = (_, certificate, chain, errors) =>
                {
+                    if ((errors & System.Net.Security.SslPolicyErrors.RemoteCertificateNameMismatch) != 0)
+                    {
+                        return false;
+                    }
+
                    if (certificate is null)
                    {
                        return false;
@@ -329,6 +362,10 @@ public sealed class MxGatewayClient : IAsyncDisposable
                    return customChain.Build(certificateToValidate);
                };
            }
+            else if (!options.RequireCertificateValidation)
+            {
+                handler.SslOptions.RemoteCertificateValidationCallback = (_, _, _, _) => true;
+            }
        }

        return handler;
@@ -336,6 +373,6 @@ public sealed class MxGatewayClient : IAsyncDisposable

    private void ThrowIfDisposed()
    {
-        ObjectDisposedException.ThrowIf(Volatile.Read(ref _disposed) != 0, this);
+        ObjectDisposedException.ThrowIf(_disposed, this);
    }
 }
@@ -0,0 +1,17 @@
+using ZB.MOM.WW.MxGateway.Contracts;
+
+namespace ZB.MOM.WW.MxGateway.Client;
+
+/// <summary>
+/// Exposes the protocol versions compiled into this client package.
+/// </summary>
+public static class MxGatewayClientContractInfo
+{
+    /// <inheritdoc cref="GatewayContractInfo.GatewayProtocolVersion"/>
+    public const uint GatewayProtocolVersion =
+        GatewayContractInfo.GatewayProtocolVersion;
+
+    /// <inheritdoc cref="GatewayContractInfo.WorkerProtocolVersion"/>
+    public const uint WorkerProtocolVersion =
+        GatewayContractInfo.WorkerProtocolVersion;
+}
@@ -1,6 +1,6 @@
 using Microsoft.Extensions.Logging;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Configures the gRPC channel used by the .NET MXAccess Gateway client.
@@ -27,6 +27,14 @@ public sealed class MxGatewayClientOptions
    /// </summary>
    public string? CaCertificatePath { get; init; }

+    /// <summary>
+    /// When true, TLS connections without a pinned <see cref="CaCertificatePath"/>
+    /// use the OS trust store. When false (default), the gateway certificate is
+    /// accepted without verification — appropriate for this internal tool's
+    /// auto-generated self-signed certificate. Pinning a CA always verifies.
+    /// </summary>
+    public bool RequireCertificateValidation { get; init; }
+
    /// <summary>
    /// Gets the server name override for SNI during TLS handshake.
    /// </summary>
@@ -38,12 +46,7 @@ public sealed class MxGatewayClientOptions
    public TimeSpan ConnectTimeout { get; init; } = TimeSpan.FromSeconds(10);

    /// <summary>
-    /// Gets the timeout budget for a unary gRPC operation. This is both the gRPC
-    /// deadline stamped on each individual attempt and the overall budget for the
-    /// whole safe-unary operation: for retryable calls the initial attempt, every
-    /// retry, and the backoff delays between them all share this single budget.
-    /// It is therefore an upper bound on the total wall-clock time a safe-unary
-    /// call can take, not a fresh per-retry allowance.
+    /// Gets the default timeout for unary gRPC calls.
    /// </summary>
    public TimeSpan DefaultCallTimeout { get; init; } = TimeSpan.FromSeconds(30);

@@ -53,9 +56,7 @@ public sealed class MxGatewayClientOptions
    public TimeSpan? StreamTimeout { get; init; }

    /// <summary>
-    /// Gets the maximum size, in bytes, of a single gRPC message the client will
-    /// send or receive. Applied to both the send and receive limits of the
-    /// underlying channel. Defaults to 16 MiB.
+    /// Gets the maximum size in bytes for gRPC messages.
    /// </summary>
    public int MaxGrpcMessageBytes { get; init; } = 16 * 1024 * 1024;

@@ -1,4 +1,4 @@
-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Configuration for automatic retry behavior on transient gRPC call failures.</summary>
 public sealed class MxGatewayClientRetryOptions
@@ -1,10 +1,10 @@
 using Grpc.Core;
 using Microsoft.Extensions.Logging;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;
 using Polly;
 using Polly.Retry;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Factory and helpers for exponential-backoff retry policies on transient gRPC failures.</summary>
 internal static class MxGatewayClientRetryPolicy
@@ -12,6 +12,7 @@ internal static class MxGatewayClientRetryPolicy
    /// <summary>Creates a Polly ResiliencePipeline that retries transient gRPC failures with exponential backoff.</summary>
    /// <param name="options">Retry configuration (max attempts, delay bounds, jitter).</param>
    /// <param name="logger">Optional logger for retry diagnostics.</param>
+    /// <returns>A configured <see cref="ResiliencePipeline"/> with exponential-backoff retry.</returns>
    public static ResiliencePipeline Create(
        MxGatewayClientRetryOptions options,
        ILogger? logger)
@@ -42,6 +43,7 @@ internal static class MxGatewayClientRetryPolicy

    /// <summary>Returns whether a command kind is eligible for automatic retry on transient failures.</summary>
    /// <param name="kind">The command kind to check.</param>
+    /// <returns><see langword="true"/> if the command kind is safe to retry; otherwise <see langword="false"/>.</returns>
    public static bool IsRetryableCommand(MxCommandKind kind)
    {
        return kind is MxCommandKind.Ping
@@ -61,13 +63,8 @@ internal static class MxGatewayClientRetryPolicy

    private static bool IsTransientStatus(StatusCode statusCode)
    {
-        // DeadlineExceeded is intentionally NOT treated as transient. The deadline
-        // on every unary call is client-imposed (CreateCallOptions stamps the
-        // DefaultCallTimeout budget), and that same budget is shared across the
-        // initial attempt plus all retries plus backoff. A DeadlineExceeded means
-        // the shared budget is exhausted, so an immediate retry would only fail
-        // again — burning the remaining budget on a call that cannot succeed.
        return statusCode is StatusCode.Unavailable
+            or StatusCode.DeadlineExceeded
            or StatusCode.ResourceExhausted;
    }
 }
@@ -1,6 +1,6 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when a gateway command fails due to an unclassified protocol error.</summary>
 public class MxGatewayCommandException : MxGatewayException
@@ -1,7 +1,6 @@
-using Grpc.Core;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Exception thrown when a gateway RPC call fails or returns an error status.
@@ -29,20 +28,6 @@ public class MxGatewayException : Exception
        Statuses = [];
    }

-    /// <summary>
-    /// Initializes a new instance of the MxGatewayException class carrying the originating
-    /// gRPC status code so callers can distinguish transient from permanent failures.
-    /// </summary>
-    /// <param name="message">Diagnostic message describing the failure.</param>
-    /// <param name="statusCode">The gRPC status code reported by the failed call.</param>
-    /// <param name="innerException">Underlying exception that caused this failure.</param>
-    public MxGatewayException(string message, StatusCode statusCode, Exception? innerException)
-        : base(message, innerException)
-    {
-        StatusCode = statusCode;
-        Statuses = [];
-    }
-
    /// <summary>
    /// Initializes a new instance of the MxGatewayException class with full diagnostic information.
    /// </summary>
@@ -53,7 +38,6 @@ public class MxGatewayException : Exception
    /// <param name="hResult">HRESULT code returned by the worker or MXAccess, if available.</param>
    /// <param name="statuses">List of MXAccess status codes returned by the operation.</param>
    /// <param name="innerException">Underlying exception that caused this failure.</param>
-    /// <param name="statusCode">The gRPC status code reported by the failed call, if available.</param>
    public MxGatewayException(
        string message,
        string? sessionId,
@@ -61,8 +45,7 @@ public class MxGatewayException : Exception
        ProtocolStatus? protocolStatus,
        int? hResult,
        IReadOnlyList<MxStatusProxy> statuses,
-        Exception? innerException = null,
-        StatusCode? statusCode = null)
+        Exception? innerException = null)
        : base(message, innerException)
    {
        SessionId = sessionId;
@@ -70,7 +53,6 @@ public class MxGatewayException : Exception
        ProtocolStatus = protocolStatus;
        HResultCode = hResult;
        Statuses = statuses;
-        StatusCode = statusCode;
    }

    /// <summary>
@@ -97,15 +79,4 @@ public class MxGatewayException : Exception
    /// Gets the list of MXAccess status codes returned by the operation.
    /// </summary>
    public IReadOnlyList<MxStatusProxy> Statuses { get; }
-
-    /// <summary>
-    /// Gets the gRPC status code reported by the failed call, if the failure originated
-    /// from a gRPC <see cref="RpcException"/>. <see langword="null"/> when the exception
-    /// was not produced from a gRPC status (for example, a protocol-level reply failure).
-    /// Callers can inspect this to distinguish a transient outage
-    /// (<see cref="Grpc.Core.StatusCode.Unavailable"/>) from a permanent error
-    /// (<see cref="Grpc.Core.StatusCode.InvalidArgument"/>) without downcasting
-    /// <see cref="Exception.InnerException"/>.
-    /// </summary>
-    public StatusCode? StatusCode { get; }
 }
@@ -1,6 +1,6 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Represents one gateway-backed MXAccess session.
@@ -9,10 +9,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
 {
    private readonly MxGatewayClient _client;
    private readonly SemaphoreSlim _closeLock = new(1, 1);
-    private readonly object _disposeGate = new();
    private CloseSessionReply? _closeReply;
-    private int _activeCloseCount;
-    private bool _closeLockDisposed;

    /// <summary>
    /// Initializes a new session backed by the given MXAccess gateway client.
@@ -49,17 +46,6 @@ public sealed class MxGatewaySession : IAsyncDisposable
            return _closeReply;
        }

-        // Register as an in-flight closer under the dispose gate. DisposeAsync waits for
-        // _activeCloseCount to drain before disposing the close lock, so the semaphore is
-        // guaranteed to outlive every WaitAsync started here.
-        lock (_disposeGate)
-        {
-            ObjectDisposedException.ThrowIf(_closeLockDisposed, this);
-            _activeCloseCount++;
-        }
-
-        try
-        {
        await _closeLock.WaitAsync(cancellationToken).ConfigureAwait(false);
        try
        {
@@ -79,14 +65,6 @@ public sealed class MxGatewaySession : IAsyncDisposable
            _closeLock.Release();
        }
    }
-        finally
-        {
-            lock (_disposeGate)
-            {
-                _activeCloseCount--;
-            }
-        }
-    }

    /// <summary>
    /// Registers a client with the MXAccess session, returning a ServerHandle.
@@ -101,8 +79,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
        MxCommandReply reply = await RegisterRawAsync(clientName, cancellationToken)
            .ConfigureAwait(false);
        reply.EnsureProtocolSuccess().EnsureMxAccessSuccess();
-        return reply.Register?.ServerHandle
-            ?? throw CreateMissingPayloadException(reply, "register");
+        return reply.Register?.ServerHandle ?? reply.ReturnValue.Int32Value;
    }

    /// <summary>
@@ -144,8 +121,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
                cancellationToken)
            .ConfigureAwait(false);
        reply.EnsureProtocolSuccess().EnsureMxAccessSuccess();
-        return reply.AddItem?.ItemHandle
-            ?? throw CreateMissingPayloadException(reply, "add_item");
+        return reply.AddItem?.ItemHandle ?? reply.ReturnValue.Int32Value;
    }

    /// <summary>
@@ -196,8 +172,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
                cancellationToken)
            .ConfigureAwait(false);
        reply.EnsureProtocolSuccess().EnsureMxAccessSuccess();
-        return reply.AddItem2?.ItemHandle
-            ?? throw CreateMissingPayloadException(reply, "add_item2");
+        return reply.AddItem2?.ItemHandle ?? reply.ReturnValue.Int32Value;
    }

    /// <summary>
@@ -236,6 +211,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <param name="serverHandle">The ServerHandle from register.</param>
    /// <param name="itemHandle">The ItemHandle from add-item.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async Task AdviseAsync(
        int serverHandle,
        int itemHandle,
@@ -277,6 +253,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <param name="serverHandle">The ServerHandle from register.</param>
    /// <param name="itemHandle">The ItemHandle from add-item.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async Task UnAdviseAsync(
        int serverHandle,
        int itemHandle,
@@ -318,6 +295,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <param name="serverHandle">The ServerHandle from register.</param>
    /// <param name="itemHandle">The ItemHandle from add-item.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async Task RemoveItemAsync(
        int serverHandle,
        int itemHandle,
@@ -529,10 +507,14 @@ public sealed class MxGatewaySession : IAsyncDisposable

    /// <summary>
    /// Bulk Write — sequential MXAccess Write per entry on the worker's STA.
-    /// Per-item failures appear as BulkWriteResult entries with
+    /// Per-item failures appear as <see cref="BulkWriteResult"/> entries with
    /// <c>WasSuccessful = false</c>; the call never throws on per-item errors.
    /// Protocol-level failures still throw via EnsureProtocolSuccess.
    /// </summary>
+    /// <param name="serverHandle">The ServerHandle from register.</param>
+    /// <param name="entries">Per-item write entries; each carries the item handle, value, and user id.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>One <see cref="BulkWriteResult"/> per requested entry, in request order.</returns>
    public async Task<IReadOnlyList<BulkWriteResult>> WriteBulkAsync(
        int serverHandle,
        IReadOnlyList<WriteBulkEntry> entries,
@@ -555,7 +537,15 @@ public sealed class MxGatewaySession : IAsyncDisposable
        return reply.WriteBulk?.Results.ToArray() ?? [];
    }

-    /// <summary>Bulk Write2 — sequential MXAccess Write2 (timestamped) per entry.</summary>
+    /// <summary>
+    /// Bulk Write2 — sequential MXAccess Write2 (timestamped) per entry.
+    /// Per-item failures appear as <see cref="BulkWriteResult"/> entries with
+    /// <c>WasSuccessful = false</c>; the call never throws on per-item errors.
+    /// </summary>
+    /// <param name="serverHandle">The ServerHandle from register.</param>
+    /// <param name="entries">Per-item write entries; each carries the item handle, value, timestamp, and user id.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>One <see cref="BulkWriteResult"/> per requested entry, in request order.</returns>
    public async Task<IReadOnlyList<BulkWriteResult>> Write2BulkAsync(
        int serverHandle,
        IReadOnlyList<Write2BulkEntry> entries,
@@ -583,6 +573,10 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// Credential-sensitive values must never reach logs; the client mirrors
    /// the single-item WriteSecured redaction contract.
    /// </summary>
+    /// <param name="serverHandle">The ServerHandle from register.</param>
+    /// <param name="entries">Per-item write entries; each carries the item handle, value, current user id, and verifier user id.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>One <see cref="BulkWriteResult"/> per requested entry, in request order.</returns>
    public async Task<IReadOnlyList<BulkWriteResult>> WriteSecuredBulkAsync(
        int serverHandle,
        IReadOnlyList<WriteSecuredBulkEntry> entries,
@@ -605,7 +599,14 @@ public sealed class MxGatewaySession : IAsyncDisposable
        return reply.WriteSecuredBulk?.Results.ToArray() ?? [];
    }

-    /// <summary>Bulk WriteSecured2 — sequential MXAccess WriteSecured2 (timestamped) per entry.</summary>
+    /// <summary>
+    /// Bulk WriteSecured2 — sequential MXAccess WriteSecured2 (timestamped) per entry.
+    /// Same redaction rules as <see cref="WriteSecuredBulkAsync"/>.
+    /// </summary>
+    /// <param name="serverHandle">The ServerHandle from register.</param>
+    /// <param name="entries">Per-item write entries; each carries the item handle, value, timestamp, current user id, and verifier user id.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>One <see cref="BulkWriteResult"/> per requested entry, in request order.</returns>
    public async Task<IReadOnlyList<BulkWriteResult>> WriteSecured2BulkAsync(
        int serverHandle,
        IReadOnlyList<WriteSecured2BulkEntry> entries,
@@ -631,11 +632,17 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <summary>
    /// Bulk Read — snapshot the current value for each requested tag.
    /// Returns the cached OnDataChange value when the tag is already advised
-    /// (was_cached = true), otherwise the worker takes the full AddItem +
+    /// (<c>WasCached = true</c>), otherwise the worker takes the full AddItem +
    /// Advise + wait + UnAdvise + RemoveItem snapshot lifecycle. Per-tag
-    /// failures (timeout, invalid tag) appear as BulkReadResult entries with
-    /// <c>WasSuccessful = false</c>; the call never throws on per-tag errors.
+    /// failures (timeout, invalid tag) appear as <see cref="BulkReadResult"/>
+    /// entries with <c>WasSuccessful = false</c>; the call never throws on
+    /// per-tag errors.
    /// </summary>
+    /// <param name="serverHandle">The ServerHandle from register.</param>
+    /// <param name="tagAddresses">Tag addresses to read (one per result).</param>
+    /// <param name="timeout">Per-call timeout for the snapshot lifecycle path; <see cref="TimeSpan.Zero"/> uses the gateway default.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>One <see cref="BulkReadResult"/> per requested tag, in request order.</returns>
    public async Task<IReadOnlyList<BulkReadResult>> ReadBulkAsync(
        int serverHandle,
        IReadOnlyList<string> tagAddresses,
@@ -671,6 +678,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <param name="value">The value to write.</param>
    /// <param name="userId">User ID context for the write.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async Task WriteAsync(
        int serverHandle,
        int itemHandle,
@@ -725,6 +733,7 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <param name="timestampValue">The timestamp to write with the value.</param>
    /// <param name="userId">User ID context for the write.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async Task Write2Async(
        int serverHandle,
        int itemHandle,
@@ -817,34 +826,10 @@ public sealed class MxGatewaySession : IAsyncDisposable
    /// <summary>
    /// Closes the session and releases resources.
    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
    public async ValueTask DisposeAsync()
    {
-        lock (_disposeGate)
-        {
-            if (_closeLockDisposed)
-            {
-                return;
-            }
-        }
-
        await CloseAsync().ConfigureAwait(false);
-
-        // Wait for every concurrent CloseAsync caller to leave the close lock before
-        // disposing it; once _closeReply is set those callers return without awaiting.
-        while (true)
-        {
-            lock (_disposeGate)
-            {
-                if (_activeCloseCount == 0)
-                {
-                    _closeLockDisposed = true;
-                    break;
-                }
-            }
-
-            await Task.Yield();
-        }
-
        _closeLock.Dispose();
    }

@@ -862,21 +847,4 @@ public sealed class MxGatewaySession : IAsyncDisposable
            cancellationToken);
    }

-    /// <summary>
-    /// Builds the exception thrown when a command reply passed protocol and
-    /// MXAccess success checks but is missing the typed handle-bearing payload
-    /// the command contract requires. Surfacing this as a clear error avoids
-    /// silently handing a zero handle to the caller (it would otherwise fall
-    /// through to <see cref="MxCommandReply.ReturnValue"/>, which is 0 when the
-    /// reply carries no return value).
-    /// </summary>
-    private static MxGatewayException CreateMissingPayloadException(
-        MxCommandReply reply,
-        string expectedPayload)
-    {
-        return new MxGatewayException(
-            $"Gateway reply for command kind={reply.Kind} reported success but is missing "
-            + $"the required '{expectedPayload}' payload; cannot resolve a handle. "
-            + $"session={reply.SessionId}; correlation={reply.CorrelationId}");
-    }
 }
@@ -1,6 +1,6 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when a session is not found, not ready, or invalid.</summary>
 public sealed class MxGatewaySessionException : MxGatewayException
@@ -1,6 +1,6 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Exception thrown when the worker process is unavailable or fails to process a command.</summary>
 public sealed class MxGatewayWorkerException : MxGatewayException
@@ -1,12 +1,13 @@
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>Extension methods for MxStatusProxy values.</summary>
 public static class MxStatusProxyExtensions
 {
    /// <summary>Returns whether the status indicates success (success flag set and category is Ok).</summary>
    /// <param name="status">The status to check.</param>
+    /// <returns><c>true</c> if the status is successful; <c>false</c> otherwise.</returns>
    public static bool IsSuccess(this MxStatusProxy status)
    {
        ArgumentNullException.ThrowIfNull(status);
@@ -17,6 +18,7 @@ public static class MxStatusProxyExtensions

    /// <summary>Returns a formatted summary of the status for diagnostic output.</summary>
    /// <param name="status">The status to summarize.</param>
+    /// <returns>A human-readable string combining category, source, detail, and diagnostic text.</returns>
    public static string ToDiagnosticSummary(this MxStatusProxy status)
    {
        ArgumentNullException.ThrowIfNull(status);
@@ -1,8 +1,8 @@
 using Google.Protobuf;
 using Google.Protobuf.WellKnownTypes;
-using MxGateway.Contracts.Proto;
+using ZB.MOM.WW.MxGateway.Contracts.Proto;

-namespace MxGateway.Client;
+namespace ZB.MOM.WW.MxGateway.Client;

 /// <summary>
 /// Creates and projects gateway MXAccess values without hiding the raw
@@ -14,6 +14,7 @@ public static class MxValueExtensions
    /// Converts a boolean value to an MxValue with MxDataType.Boolean.
    /// </summary>
    /// <param name="value">Scalar boolean value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Boolean</c>.</returns>
    public static MxValue ToMxValue(this bool value)
    {
        return new MxValue
@@ -28,6 +29,7 @@ public static class MxValueExtensions
    /// Converts a 32-bit integer value to an MxValue with MxDataType.Integer.
    /// </summary>
    /// <param name="value">32-bit integer value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Integer</c>.</returns>
    public static MxValue ToMxValue(this int value)
    {
        return new MxValue
@@ -42,6 +44,7 @@ public static class MxValueExtensions
    /// Converts a 64-bit integer value to an MxValue with MxDataType.Integer.
    /// </summary>
    /// <param name="value">64-bit integer value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Integer</c>.</returns>
    public static MxValue ToMxValue(this long value)
    {
        return new MxValue
@@ -56,6 +59,7 @@ public static class MxValueExtensions
    /// Converts a single-precision floating-point value to an MxValue with MxDataType.Float.
    /// </summary>
    /// <param name="value">Single-precision floating-point value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Float</c>.</returns>
    public static MxValue ToMxValue(this float value)
    {
        return new MxValue
@@ -70,6 +74,7 @@ public static class MxValueExtensions
    /// Converts a double-precision floating-point value to an MxValue with MxDataType.Double.
    /// </summary>
    /// <param name="value">Double-precision floating-point value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Double</c>.</returns>
    public static MxValue ToMxValue(this double value)
    {
        return new MxValue
@@ -84,6 +89,7 @@ public static class MxValueExtensions
    /// Converts a string value to an MxValue with MxDataType.String.
    /// </summary>
    /// <param name="value">String value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.String</c>.</returns>
    public static MxValue ToMxValue(this string value)
    {
        ArgumentNullException.ThrowIfNull(value);
@@ -100,6 +106,7 @@ public static class MxValueExtensions
    /// Converts a DateTimeOffset value to an MxValue with MxDataType.Time.
    /// </summary>
    /// <param name="value">DateTimeOffset value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Time</c>.</returns>
    public static MxValue ToMxValue(this DateTimeOffset value)
    {
        return new MxValue
@@ -114,6 +121,7 @@ public static class MxValueExtensions
    /// Converts a DateTime value to an MxValue with MxDataType.Time.
    /// </summary>
    /// <param name="value">DateTime value to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Time</c>.</returns>
    public static MxValue ToMxValue(this DateTime value)
    {
        return new DateTimeOffset(
@@ -127,6 +135,7 @@ public static class MxValueExtensions
    /// Converts a boolean array to an MxValue with MxDataType.Boolean.
    /// </summary>
    /// <param name="values">Array of boolean values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Boolean</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<bool> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -145,6 +154,7 @@ public static class MxValueExtensions
    /// Converts a 32-bit integer array to an MxValue with MxDataType.Integer.
    /// </summary>
    /// <param name="values">Array of 32-bit integer values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Integer</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<int> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -163,6 +173,7 @@ public static class MxValueExtensions
    /// Converts a 64-bit integer array to an MxValue with MxDataType.Integer.
    /// </summary>
    /// <param name="values">Array of 64-bit integer values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Integer</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<long> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -181,6 +192,7 @@ public static class MxValueExtensions
    /// Converts a single-precision floating-point array to an MxValue with MxDataType.Float.
    /// </summary>
    /// <param name="values">Array of single-precision floating-point values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Float</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<float> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -199,6 +211,7 @@ public static class MxValueExtensions
    /// Converts a double-precision floating-point array to an MxValue with MxDataType.Double.
    /// </summary>
    /// <param name="values">Array of double-precision floating-point values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Double</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<double> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -217,6 +230,7 @@ public static class MxValueExtensions
    /// Converts a string array to an MxValue with MxDataType.String.
    /// </summary>
    /// <param name="values">Array of string values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.String</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<string> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -235,6 +249,7 @@ public static class MxValueExtensions
    /// Converts a DateTimeOffset array to an MxValue with MxDataType.Time.
    /// </summary>
    /// <param name="values">Array of DateTimeOffset values to wrap.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Time</c> and an array payload.</returns>
    public static MxValue ToMxValue(this IReadOnlyList<DateTimeOffset> values)
    {
        ArgumentNullException.ThrowIfNull(values);
@@ -253,6 +268,7 @@ public static class MxValueExtensions
    /// Gets the projection kind (field name) of the given MxValue's current oneof value.
    /// </summary>
    /// <param name="value">The MxValue whose oneof projection kind is returned.</param>
+    /// <returns>The JSON field name of the active oneof case, or <c>"nullValue"</c>/<c>"unspecified"</c> for null/unset values.</returns>
    public static string GetProjectionKind(this MxValue value)
    {
        ArgumentNullException.ThrowIfNull(value);
@@ -276,6 +292,7 @@ public static class MxValueExtensions
    /// Converts an MxValue to a CLR object; returns the boxed value or null for null MxValues.
    /// </summary>
    /// <param name="value">The MxValue to convert.</param>
+    /// <returns>The boxed CLR value, or null if the MxValue represents a null.</returns>
    public static object? ToClrValue(this MxValue value)
    {
        ArgumentNullException.ThrowIfNull(value);
@@ -299,6 +316,7 @@ public static class MxValueExtensions
    /// Converts an MxArray to a CLR array; returns null if the array does not have a known element type.
    /// </summary>
    /// <param name="array">The MxArray to convert.</param>
+    /// <returns>A CLR array of the appropriate element type, or null for unknown element types.</returns>
    public static object? ToClrArrayValue(this MxArray array)
    {
        ArgumentNullException.ThrowIfNull(array);
@@ -328,6 +346,7 @@ public static class MxValueExtensions
    /// <param name="variantType">Variant type string (e.g., "VT_BSTR").</param>
    /// <param name="rawDiagnostic">Diagnostic string describing the raw value.</param>
    /// <param name="rawDataType">Optional MXAccess data type override.</param>
+    /// <returns>An <see cref="MxValue"/> with <c>MxDataType.Unknown</c> and the raw byte payload.</returns>
    public static MxValue ToRawMxValue(
        byte[] value,
        string variantType,
@@ -0,0 +1,3 @@
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("ZB.MOM.WW.MxGateway.Client.Tests")]
@@ -0,0 +1,36 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\src\ZB.MOM.WW.MxGateway.Contracts\ZB.MOM.WW.MxGateway.Contracts.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Grpc.Net.Client" Version="2.76.0" />
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.7" />
+    <PackageReference Include="Polly.Core" Version="8.6.6" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <IsPackable>true</IsPackable>
+    <PackageId>ZB.MOM.WW.MxGateway.Client</PackageId>
+    <Description>.NET 10 gRPC client for the MxAccessGateway service. Provides typed wrappers, retry, and a lazy-browse walker over the Galaxy Repository hierarchy.</Description>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <None Include="..\README.md" Pack="true" PackagePath="\" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
+      <_Parameter1>ZB.MOM.WW.MxGateway.Client.Tests</_Parameter1>
+    </AssemblyAttribute>
+  </ItemGroup>
+
+</Project>
@@ -104,6 +104,23 @@ Support:
 - `credentials.NewClientTLSFromFile`,
 - custom `tls.Config` for advanced callers.

+### Trust posture
+
+The gateway can serve a self-signed certificate it generates itself (it has no
+PKI). To make that usable, TLS is **lenient by default**: when `Plaintext` is
+`false` and no `CACertFile`/`TLSConfig`/`TransportCredentials` is supplied,
+`buildCredentials` dials with `tls.Config{InsecureSkipVerify: true}` (carrying
+`ServerNameOverride` as the SNI when set), so the gateway's self-signed
+certificate is accepted without verification.
+
+To verify the gateway instead:
+
+- set `CACertFile` to pin a CA (full verification against that root), or
+- set `RequireCertificateValidation: true` to verify against the OS/system trust
+  roots without pinning.
+
+Pinning a CA always wins over the lenient default.
+
 ## Streaming

 `Events(ctx)` should return a receive channel of:
@@ -75,42 +75,29 @@ client, err := mxgateway.Dial(ctx, mxgateway.Options{
 })
 ```

+The gateway can auto-generate its own self-signed certificate (it has no PKI), so
+the client is **lenient by default**: a TLS connection (`Plaintext: false`) with
+no `CACertFile`/`TLSConfig` accepts whatever certificate the gateway presents
+(`InsecureSkipVerify`, with `ServerNameOverride` as the SNI when set). To verify
+instead, set `CACertFile` to pin a CA, or set `RequireCertificateValidation:
+true` to verify against the OS/system trust roots without pinning. See
+[Gateway Configuration](../../docs/GatewayConfiguration.md#automatic-self-signed-certificate).
+
 `Client.OpenSession` returns a `Session` with helpers for `Register`,
-`AddItem`, `AddItem2`, `Advise`, `Write`, the full bulk family
-(`AddItemBulk`, `AdviseItemBulk`, `RemoveItemBulk`, `UnAdviseItemBulk`,
-`SubscribeBulk`, `UnsubscribeBulk`, `WriteBulk`, `Write2Bulk`,
-`WriteSecuredBulk`, `WriteSecured2Bulk`, `ReadBulk`), `Events`, and
-`Close`. Bulk variants carry a list of entries in one round-trip and
-return one result per entry; per-entry MXAccess failures appear as
-`was_successful = false` and never return as Go errors. `ReadBulk` accepts
-a `time.Duration` per-tag timeout and returns cached `OnDataChange`
-values when the tag is already advised (`WasCached = true`) without
-touching the existing subscription. Prefer
+`AddItem`, `AddItem2`, `Advise`, `Write`, `Events`, and `Close`. Prefer
 `SubscribeEvents` or `SubscribeEventsAfter` for long-running streams because the
 returned subscription owns cancellation and exposes `Close` for deterministic
-goroutine cleanup. `Events` and `EventsAfter` are a compatibility shim with a
-bounded internal buffer: if the consumer drains too slowly the buffer fills,
-the underlying stream is cancelled, and a terminal `EventResult` carrying
-`ErrEventBufferOverflow` is delivered as the channel's last item before it
-closes — so a slow consumer can distinguish dropped events from a normal
-end-of-stream. `SubscribeEvents` blocks instead of dropping, so use it when no
-events may be lost. Raw protobuf messages remain available through the
+goroutine cleanup. Raw protobuf messages remain available through the
 `mxgateway` package aliases and the `Raw` helper methods. Typed errors support
 `errors.As` for `GatewayError`, `CommandError`, and `MxAccessError`; command
 errors preserve the raw reply.

-`Dial` and `DialGalaxy` create the connection lazily (`grpc.NewClient`): a
-gateway that is briefly unavailable no longer turns into a hard error — the
-connection recovers once the gateway comes up. To keep fail-fast behavior,
-both run a readiness probe bounded by `DialTimeout` (default 10s, or the
-context deadline when sooner) and return a `*GatewayError` if the gateway
-cannot be reached in that window.
-
-For retry, timeout, and auth handling, `GatewayError.Code()` exposes the
-wrapped gRPC `codes.Code`, and `mxgateway.IsTransient(err)` reports whether a
-failure (`Unavailable`, `DeadlineExceeded`, `ResourceExhausted`, `Aborted`)
-may succeed on retry — so callers do not have to unwrap the error and call
-`status.Code` themselves.
+For alarms, the package exposes `Client.QueryActiveAlarms` for one-shot
+snapshots, `Client.StreamAlarms` for the server-streaming feed, and
+`Client.AcknowledgeAlarm` to ack an alarm by full reference. The streaming
+call returns a `StreamAlarmsClient`; cancel its context to terminate the
+stream. All three pass straight through to the gateway's central alarm
+monitor.

 ## Galaxy Repository browse

@@ -142,6 +129,68 @@ reports `present=false` (no deploy recorded). `DiscoverHierarchy` returns
 the generated `*GalaxyObject` slice with each object's dynamic attributes
 populated for direct contract access.

+### Browsing lazily
+
+For UI trees or OPC UA bridges, use `BrowseChildren` to walk one level at a
+time instead of loading the full hierarchy. Pass an empty request for root
+objects; subsequent calls set `ParentGobjectId`, `ParentTagName`, or
+`ParentContainedPath`. Filter fields match `DiscoverHierarchy`. Each response
+pairs `Children` with `ChildHasChildren` so you know which nodes to expand. See
+[Galaxy Repository](../../docs/GalaxyRepository.md#browsechildren) for full
+request and filter semantics.
+
+```go
+import pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated/galaxy_repository/v1"
+
+reply, err := galaxy.BrowseChildren(ctx, &pb.BrowseChildrenRequest{})
+if err != nil {
+    return err
+}
+for i, child := range reply.GetChildren() {
+    fmt.Printf("%s expand=%v\n", child.GetTagName(), reply.GetChildHasChildren()[i])
+}
+```
+
+#### High-level walker
+
+For UI trees, the client provides a `LazyBrowseNode` walker that handles
+sibling pagination and the `child_has_children` hint for you:
+
+```go
+galaxy, err := mxgateway.DialGalaxy(ctx, mxgateway.Options{
+    Endpoint:  "localhost:5000",
+    APIKey:    os.Getenv("MXGATEWAY_API_KEY"),
+    Plaintext: true,
+})
+if err != nil {
+    log.Fatal(err)
+}
+defer galaxy.Close()
+
+roots, err := galaxy.Browse(ctx, nil)
+if err != nil {
+    log.Fatal(err)
+}
+for _, root := range roots {
+    if root.HasChildrenHint() {
+        if err := root.Expand(ctx); err != nil {
+            log.Fatal(err)
+        }
+    }
+    for _, child := range root.Children() {
+        kind := "leaf"
+        if child.HasChildrenHint() {
+            kind = "has children"
+        }
+        fmt.Printf("%s (%s)\n", child.Object().GetTagName(), kind)
+    }
+}
+```
+
+`Expand` is idempotent — calling it twice fires only one RPC,
+and is safe under concurrent callers. To refresh after a Galaxy redeploy, call
+`Browse` again from the root.
+
 ### Watching deploy events

 `WatchDeployEvents` opens a server-streaming subscription. The server emits a
@@ -186,8 +235,7 @@ The CLI exposes the same RPC via `galaxy-watch`:
 ```powershell
 go run ./cmd/mxgw-go galaxy-watch -plaintext
 go run ./cmd/mxgw-go galaxy-watch -plaintext -json
-go run ./cmd/mxgw-go galaxy-watch -plaintext -last-seen-deploy-time 2026-04-28T10:00:00Z      # whole-second RFC 3339
-go run ./cmd/mxgw-go galaxy-watch -plaintext -last-seen-deploy-time 2026-04-28T10:00:00.123Z  # fractional seconds also accepted
+go run ./cmd/mxgw-go galaxy-watch -plaintext -last-seen-deploy-time 2026-04-28T10:00:00Z
 go run ./cmd/mxgw-go galaxy-watch -plaintext -limit 5
 ```

@@ -235,6 +283,38 @@ $env:MXGATEWAY_TEST_ITEM = 'Area001.Tag.Value'
 go run ./cmd/mxgw-go smoke -endpoint $env:MXGATEWAY_ENDPOINT -plaintext -api-key-env MXGATEWAY_API_KEY -item $env:MXGATEWAY_TEST_ITEM -json
 ```

+## Installing the Go client
+
+The module is resolved directly from the git repo — no package registry:
+
+````bash
+go get gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go@v0.1.0
+````
+
+Then import:
+
+````go
+import "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/mxgateway"
+````
+
+If your build environment cannot reach `gitea.dohertylan.com` directly,
+configure `GOPROXY` to point at an internal proxy that fronts the Gitea
+repo, or use `GONOSUMCHECK` + `GOPRIVATE` to bypass the checksum database
+for the internal module path.
+
+## Releasing a new version
+
+Go modules in monorepo subdirectories use prefixed tags. To tag a release
+from this repo:
+
+````bash
+pwsh scripts/tag-go-module.ps1 -Version v0.1.1 -Push
+````
+
+The script validates semver, refuses to tag with uncommitted tracked
+changes, creates an annotated tag `clients/go/v0.1.1`, and (with `-Push`)
+pushes it to origin.
+
 ## Related Documentation

 - [Client Packaging](../../docs/ClientPackaging.md)
@@ -351,17 +351,17 @@ func runUnsubscribeBulk(ctx context.Context, args []string, stdout, stderr io.Wr
 		return errors.New("session-id and item-handles are required")
 	}

-	handles, err := parseInt32List(*itemHandles)
-	if err != nil {
-		return err
-	}
-
 	client, options, err := dialForCommand(ctx, common)
 	if err != nil {
 		return err
 	}
 	defer client.Close()

+	handles, err := parseInt32List(*itemHandles)
+	if err != nil {
+		return err
+	}
+
 	session := mxgateway.NewSessionForID(client, *sessionID)
 	results, err := session.UnsubscribeBulk(ctx, int32(*serverHandle), handles)
 	return writeBulkOutput(stdout, *jsonOutput, "unsubscribe-bulk", options, results, err)
@@ -412,14 +412,15 @@ func runWriteSecured2Bulk(ctx context.Context, args []string, stdout, stderr io.
 }

 // runWriteBulkVariant shares the flag-parsing + entry-build skeleton across
-// the four bulk-write families. command selects which of the four routes
-// runs; withTimestamp adds a --timestamp-value flag for the Write2 / Secured2
-// variants. Secured-only flags (--current-user-id / --verifier-user-id) are
-// only registered for the secured variants and the non-secured -user-id flag
-// is only registered for Write/Write2, so a wrong-variant flag becomes a
-// clean "flag provided but not defined" error instead of silently no-op'ing.
+// the four bulk-write families. The variant is derived from command alone;
+// withTimestamp adds a --timestamp-value flag. To keep wrong-variant flags
+// from silently no-op'ing, secured-only flags (-current-user-id /
+// -verifier-user-id) are only registered for the secured variants, and
+// -user-id only for the non-secured Write/Write2 variants — a wrong-variant
+// flag then surfaces as a clean "flag provided but not defined" error.
 func runWriteBulkVariant(ctx context.Context, args []string, stdout, stderr io.Writer, command string, withTimestamp bool) error {
 	secured := command == "write-secured-bulk" || command == "write-secured2-bulk"
+
 	flags := flag.NewFlagSet(command, flag.ContinueOnError)
 	flags.SetOutput(stderr)
 	common := bindCommonFlags(flags)
@@ -429,7 +430,11 @@ func runWriteBulkVariant(ctx context.Context, args []string, stdout, stderr io.W
 	itemHandles := flags.String("item-handles", "", "comma-separated item handles")
 	valueType := flags.String("type", "string", "value type: bool, int32, int64, float, double, string")
 	values := flags.String("values", "", "comma-separated values (one per item handle)")
-	var userID, currentUserID, verifierUserID *int
+	var (
+		userID         *int
+		currentUserID  *int
+		verifierUserID *int
+	)
 	if secured {
 		currentUserID = flags.Int("current-user-id", 0, "MXAccess current user id (Secured variants)")
 		verifierUserID = flags.Int("verifier-user-id", 0, "MXAccess verifier user id (Secured variants)")
@@ -526,6 +531,16 @@ func runWriteBulkVariant(ctx context.Context, args []string, stdout, stderr io.W
 	return writeWriteBulkOutput(stdout, *jsonOutput, command, options, results, err)
 }

+// parseRfc3339Timestamp parses an RFC 3339 timestamp and returns the
+// MxValue protobuf representation used for the timestamped write families.
+func parseRfc3339Timestamp(text string) (*mxgateway.MxValue, error) {
+	t, err := time.Parse(time.RFC3339Nano, text)
+	if err != nil {
+		return nil, fmt.Errorf("invalid RFC 3339 timestamp %q: %w", text, err)
+	}
+	return mxgateway.TimestampValue(t), nil
+}
+
 // runBenchReadBulk drives the cross-language ReadBulk stress benchmark from Go:
 // opens its own session, subscribes to bulk-size tags so the worker value cache
 // populates from real OnDataChange events, runs ReadBulk in a tight loop for
@@ -596,19 +611,16 @@ func runBenchReadBulk(ctx context.Context, args []string, stdout, stderr io.Writ
 	}()

 	// Warm-up: drive identical calls so any first-call JIT / connection-pool
-	// setup is amortised before the measurement window opens. Honor ctx so
-	// Ctrl+C or a parent-cancel (e.g. the cross-language bench driver killing
-	// the child early) exits promptly rather than spinning failing calls until
-	// the wall-clock deadline.
+	// setup is amortised before the measurement window opens. The ctx.Err()
+	// guard short-circuits on Ctrl+C / parent-cancel instead of spinning
+	// failing ReadBulk calls until the wall-clock deadline elapses.
 	warmupDeadline := time.Now().Add(time.Duration(*warmupSeconds) * time.Second)
 	timeout := time.Duration(*timeoutMs) * time.Millisecond
 	for time.Now().Before(warmupDeadline) && ctx.Err() == nil {
 		_, _ = session.ReadBulk(ctx, serverHandle, tags, timeout)
 	}

-	// Steady state: per-call latency captured via time.Now() deltas. Same ctx
-	// guard as warm-up; on cancel we stop the loop and report the truncated
-	// window faithfully.
+	// Steady state: per-call latency captured via time.Now() deltas.
 	latenciesMs := make([]float64, 0, 65536)
 	var totalReadResults int64
 	var cachedReadResults int64
@@ -676,7 +688,7 @@ func percentileSummary(sample []float64) map[string]float64 {
 	sorted := append([]float64(nil), sample...)
 	sort.Float64s(sorted)
 	mean := 0.0
-	max := sorted[len(sorted)-1]
+	maxValue := sorted[len(sorted)-1]
 	for _, v := range sample {
 		mean += v
 	}
@@ -685,7 +697,7 @@ func percentileSummary(sample []float64) map[string]float64 {
 		"p50":  roundTo(percentile(sorted, 0.50), 3),
 		"p95":  roundTo(percentile(sorted, 0.95), 3),
 		"p99":  roundTo(percentile(sorted, 0.99), 3),
-		"max":  roundTo(max, 3),
+		"max":  roundTo(maxValue, 3),
 		"mean": roundTo(mean, 3),
 	}
 }
@@ -717,16 +729,6 @@ func roundTo(value float64, digits int) float64 {
 	return float64(int64(value*shift+0.5)) / shift
 }

-// parseRfc3339Timestamp parses an RFC 3339 timestamp and returns the
-// MxValue protobuf representation used for the timestamped write families.
-func parseRfc3339Timestamp(text string) (*mxgateway.MxValue, error) {
-	t, err := time.Parse(time.RFC3339Nano, text)
-	if err != nil {
-		return nil, fmt.Errorf("invalid RFC 3339 timestamp %q: %w", text, err)
-	}
-	return mxgateway.TimestampValue(t), nil
-}
-
 func runWrite(ctx context.Context, args []string, stdout, stderr io.Writer) error {
 	flags := flag.NewFlagSet("write", flag.ContinueOnError)
 	flags.SetOutput(stderr)
@@ -784,15 +786,8 @@ func runStreamEvents(ctx context.Context, args []string, stdout, stderr io.Write
 	}
 	defer client.Close()

-	// Mirror runGalaxyWatch so Ctrl+C on a long-running stream-events command
-	// cancels the gRPC stream cleanly (the gateway sees codes.Canceled rather
-	// than a torn TCP connection) and the deferred subscription.Close() /
-	// client.Close() actually run.
-	signalCtx, stopSignals := signal.NotifyContext(ctx, os.Interrupt, syscall.SIGTERM)
-	defer stopSignals()
-
 	session := mxgateway.NewSessionForID(client, *sessionID)
-	streamCtx, cancelStream := context.WithCancel(signalCtx)
+	streamCtx, cancelStream := context.WithCancel(ctx)
 	defer cancelStream()
 	subscription, err := session.SubscribeEventsAfter(streamCtx, *after)
 	if err != nil {
@@ -1088,31 +1083,31 @@ func parseValue(valueType, valueText string) (*mxgateway.MxValue, error) {
 	case "bool":
 		value, err := strconv.ParseBool(valueText)
 		if err != nil {
-			return nil, fmt.Errorf("invalid -value for -type %s: %q: %w", valueType, valueText, err)
+			return nil, err
 		}
 		return mxgateway.BoolValue(value), nil
 	case "int32":
 		value, err := strconv.ParseInt(valueText, 10, 32)
 		if err != nil {
-			return nil, fmt.Errorf("invalid -value for -type %s: %q: %w", valueType, valueText, err)
+			return nil, err
 		}
 		return mxgateway.Int32Value(int32(value)), nil
 	case "int64":
 		value, err := strconv.ParseInt(valueText, 10, 64)
 		if err != nil {
-			return nil, fmt.Errorf("invalid -value for -type %s: %q: %w", valueType, valueText, err)
+			return nil, err
 		}
 		return mxgateway.Int64Value(value), nil
 	case "float":
 		value, err := strconv.ParseFloat(valueText, 32)
 		if err != nil {
-			return nil, fmt.Errorf("invalid -value for -type %s: %q: %w", valueType, valueText, err)
+			return nil, err
 		}
 		return mxgateway.FloatValue(float32(value)), nil
 	case "double":
 		value, err := strconv.ParseFloat(valueText, 64)
 		if err != nil {
-			return nil, fmt.Errorf("invalid -value for -type %s: %q: %w", valueType, valueText, err)
+			return nil, err
 		}
 		return mxgateway.DoubleValue(value), nil
 	case "string":
@@ -1200,6 +1195,10 @@ type protojsonMessage interface {
 	ProtoReflect() protoreflect.Message
 }

+func writeUsage(writer io.Writer) {
+	fmt.Fprintln(writer, "usage: mxgw-go <version|open-session|close-session|register|add-item|advise|subscribe-bulk|unsubscribe-bulk|read-bulk|write-bulk|write2-bulk|write-secured-bulk|write-secured2-bulk|bench-read-bulk|write|stream-events|stream-alarms|acknowledge-alarm|smoke|galaxy-test-connection|galaxy-last-deploy|galaxy-discover|galaxy-watch|batch>")
+}
+
 // batchEOR is the end-of-result sentinel emitted to stdout after every command
 // in batch mode, regardless of success or failure.
 const batchEOR = "__MXGW_BATCH_EOR__"
@@ -1207,18 +1206,28 @@ const batchEOR = "__MXGW_BATCH_EOR__"
 // runBatch reads one command line at a time from in, dispatches each via the
 // normal runWithIO routing, and writes a batchEOR sentinel to stdout after
 // every result. Errors are serialised as JSON to stdout (not stderr) so the
-// harness can parse them without interleaving stderr. The loop never terminates
-// on command error; only stdin EOF (or an empty line) ends the session.
+// harness can parse them without interleaving stderr. Blank lines are
+// skipped; only stdin EOF ends the session.
+//
+// The scanner buffer is widened to 16 MiB so a single long command line
+// (e.g. a bulk-write with several thousand handles) does not trip the
+// default 64 KiB bufio.Scanner token-too-long error and abort the session.
+// If a line still exceeds the cap, the error is surfaced as a per-command
+// error-with-sentinel and the session continues.
 func runBatch(ctx context.Context, in io.Reader, stdout, stderr io.Writer) error {
 	bw := bufio.NewWriter(stdout)
 	scanner := bufio.NewScanner(in)
-	for scanner.Scan() {
-		line := scanner.Text()
-		if line == "" {
+	scanner.Buffer(make([]byte, 0, 64*1024), 16*1024*1024)
+	for {
+		if !scanner.Scan() {
 			break
 		}
+		line := scanner.Text()
 		args := strings.Fields(line)
 		if len(args) == 0 {
+			// Skip blank / whitespace-only lines; do NOT terminate. The
+			// session ends only on stdin EOF so a stray blank line in a
+			// PowerShell here-string does not silently drop later commands.
 			continue
 		}
 		if err := runWithIO(ctx, args, bw, stderr); err != nil {
@@ -1233,11 +1242,21 @@ func runBatch(ctx context.Context, in io.Reader, stdout, stderr io.Writer) error
 		_, _ = fmt.Fprintln(bw, batchEOR)
 		_ = bw.Flush()
 	}
-	return scanner.Err()
-}
-
-func writeUsage(writer io.Writer) {
-	fmt.Fprintln(writer, "usage: mxgw-go <version|open-session|close-session|register|add-item|advise|subscribe-bulk|unsubscribe-bulk|read-bulk|write-bulk|write2-bulk|write-secured-bulk|write-secured2-bulk|bench-read-bulk|write|stream-events|stream-alarms|acknowledge-alarm|smoke|galaxy-test-connection|galaxy-last-deploy|galaxy-discover|galaxy-watch|batch>")
+	if err := scanner.Err(); err != nil {
+		// Emit the scanner failure as a final error-with-sentinel so the
+		// harness sees the failure framed, then return the error so the
+		// process exit reflects it. This handles bufio.ErrTooLong for any
+		// pathological line above the 16 MiB cap.
+		errPayload := map[string]string{
+			"error": err.Error(),
+			"type":  "error",
+		}
+		_ = writeJSON(bw, errPayload)
+		_, _ = fmt.Fprintln(bw, batchEOR)
+		_ = bw.Flush()
+		return err
+	}
+	return nil
 }

 func dialGalaxyForCommand(ctx context.Context, common *commonOptions) (*mxgateway.GalaxyClient, commonOptions, error) {
@@ -1369,7 +1388,7 @@ func runGalaxyWatch(ctx context.Context, args []string, stdout, stderr io.Writer
 	flags.SetOutput(stderr)
 	common := bindCommonFlags(flags)
 	jsonOutput := flags.Bool("json", false, "write JSON output")
-	lastSeen := flags.String("last-seen-deploy-time", "", "RFC 3339 timestamp (with optional fractional seconds); when set, suppresses the bootstrap event")
+	lastSeen := flags.String("last-seen-deploy-time", "", "RFC3339 timestamp; when set, suppresses the bootstrap event")
 	limit := flags.Int("limit", 0, "maximum events to read; 0 means unbounded (Ctrl+C to stop)")

 	if err := flags.Parse(args); err != nil {
@@ -1378,11 +1397,7 @@ func runGalaxyWatch(ctx context.Context, args []string, stdout, stderr io.Writer

 	var lastSeenPtr *time.Time
 	if *lastSeen != "" {
-		// Use RFC3339Nano so values copy-pasted from galaxy-watch -json output
-		// (which formatDeployEvent emits with fractional seconds) round-trip;
-		// RFC3339Nano also accepts whole-second values, so the layout switch is
-		// strictly broader than the previous time.RFC3339 parse.
-		parsed, err := time.Parse(time.RFC3339Nano, *lastSeen)
+		parsed, err := time.Parse(time.RFC3339, *lastSeen)
 		if err != nil {
 			return fmt.Errorf("invalid -last-seen-deploy-time: %w", err)
 		}
@@ -1425,9 +1440,6 @@ func runGalaxyWatch(ctx context.Context, args []string, stdout, stderr io.Writer
 			count++
 			if *limit > 0 && count >= *limit {
 				cancelStream()
-				// Allow goroutine to drain.
-				for range events {
-				}
 				return nil
 			}
 		case streamErr, ok := <-errs:
@@ -2,10 +2,15 @@ package main

 import (
 	"bytes"
+	"context"
 	"encoding/json"
-	"errors"
+	"net"
 	"strings"
 	"testing"
+	"time"
+
+	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
+	"google.golang.org/grpc"
 )

 func TestRunVersionJSON(t *testing.T) {
@@ -48,6 +53,34 @@ func TestCommonOptionsRedactsAPIKey(t *testing.T) {
 	}
 }

+func TestRunBatchEmitsEORAfterVersion(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+
+	in := strings.NewReader("version --json\n")
+	if err := runBatch(t.Context(), in, &stdout, &stderr); err != nil {
+		t.Fatalf("runBatch() error = %v; stderr = %s", err, stderr.String())
+	}
+
+	out := stdout.String()
+	if !strings.Contains(out, "\n"+batchEOR+"\n") && !strings.HasSuffix(out, batchEOR+"\n") {
+		t.Fatalf("expected EOR marker %q in stdout; got: %q", batchEOR, out)
+	}
+
+	idx := strings.Index(out, batchEOR)
+	if idx <= 0 {
+		t.Fatalf("EOR marker not found or appeared before any output: %q", out)
+	}
+	payload := out[:idx]
+	var output versionOutput
+	if err := json.Unmarshal([]byte(payload), &output); err != nil {
+		t.Fatalf("parse JSON block before EOR: %v (payload=%q)", err, payload)
+	}
+	if output.GatewayProtocolVersion == 0 || output.WorkerProtocolVersion == 0 {
+		t.Fatalf("protocol versions were not populated: %+v", output)
+	}
+}
+
 func TestParseValueBuildsTypedValue(t *testing.T) {
 	value, err := parseValue("int32", "123")
 	if err != nil {
@@ -58,194 +91,206 @@ func TestParseValueBuildsTypedValue(t *testing.T) {
 	}
 }

-func TestParseInt32ListParsesValidTokens(t *testing.T) {
-	items, err := parseInt32List("1, 2 ,3")
-	if err != nil {
-		t.Fatalf("parseInt32List() error = %v", err)
-	}
-	want := []int32{1, 2, 3}
-	if len(items) != len(want) {
-		t.Fatalf("parseInt32List() = %v, want %v", items, want)
-	}
-	for i := range want {
-		if items[i] != want[i] {
-			t.Fatalf("parseInt32List()[%d] = %d, want %d", i, items[i], want[i])
-		}
-	}
-}
-
-func TestParseInt32ListReturnsErrorOnMalformedToken(t *testing.T) {
-	items, err := parseInt32List("1,foo")
-	if err == nil {
-		t.Fatalf("parseInt32List() error = nil, want a parse error; items = %v", items)
-	}
-	if items != nil {
-		t.Fatalf("parseInt32List() items = %v, want nil on error", items)
-	}
-	if !strings.Contains(err.Error(), "foo") {
-		t.Fatalf("parseInt32List() error = %q, want it to name the bad token", err.Error())
-	}
-}
-
-// TestParseValueWrapsStrconvErrorWithFlagContext pins Client.Go-017: each
-// typed branch of parseValue wraps the bare strconv error with `%w` and names
-// the offending flag and value, so the CLI surface is consistent with
-// parseInt32List ("invalid item handle %q: %w") and parseRfc3339Timestamp
-// ("invalid RFC 3339 timestamp %q: %w").
-func TestParseValueWrapsStrconvErrorWithFlagContext(t *testing.T) {
-	cases := []struct {
-		valueType string
-		valueText string
-	}{
-		{"bool", "notabool"},
-		{"int32", "foo"},
-		{"int64", "foo"},
-		{"float", "notafloat"},
-		{"double", "notadouble"},
-	}
-	for _, tc := range cases {
-		t.Run(tc.valueType, func(t *testing.T) {
-			_, err := parseValue(tc.valueType, tc.valueText)
-			if err == nil {
-				t.Fatalf("parseValue(%q, %q) error = nil, want a parse error", tc.valueType, tc.valueText)
-			}
-			msg := err.Error()
-			if !strings.Contains(msg, "-value") {
-				t.Fatalf("parseValue() error = %q, want it to name the -value flag", msg)
-			}
-			if !strings.Contains(msg, tc.valueType) {
-				t.Fatalf("parseValue() error = %q, want it to name the type %q", msg, tc.valueType)
-			}
-			if !strings.Contains(msg, tc.valueText) {
-				t.Fatalf("parseValue() error = %q, want it to name the bad token %q", msg, tc.valueText)
-			}
-			// errors.Unwrap must reach the underlying strconv error so callers
-			// can still errors.Is/As against strconv.ErrSyntax if they care.
-			if errors.Unwrap(err) == nil {
-				t.Fatalf("parseValue() returned unwrapped error %q, want a %%w wrap", msg)
-			}
-		})
-	}
-}
-
-// TestRunWriteBulkVariantGatesSecuredFlags pins the Client.Go-015 fix at the
-// CLI surface: secured-only flags (-current-user-id, -verifier-user-id) must
-// not be registered on the non-secured variants, and -user-id must not be
-// registered on the secured variants. The flag package rejects an unknown
-// flag with "flag provided but not defined", which a future refactor that
-// re-broadens flag registration would silently undo without this test.
+// TestRunWriteBulkVariantGatesSecuredFlags pins the Client.Go-022 fix:
+// secured-only flags must be unavailable on non-secured variants, and
+// vice-versa, so a wrong-variant flag fails with a clean "flag provided
+// but not defined" error instead of silently no-op'ing.
 func TestRunWriteBulkVariantGatesSecuredFlags(t *testing.T) {
-	cases := []struct {
-		name    string
-		command string
-		flag    string
-	}{
-		{"write-bulk rejects -current-user-id", "write-bulk", "-current-user-id"},
-		{"write-bulk rejects -verifier-user-id", "write-bulk", "-verifier-user-id"},
-		{"write2-bulk rejects -current-user-id", "write2-bulk", "-current-user-id"},
-		{"write-secured-bulk rejects -user-id", "write-secured-bulk", "-user-id"},
-		{"write-secured2-bulk rejects -user-id", "write-secured2-bulk", "-user-id"},
-	}
-	for _, tc := range cases {
-		t.Run(tc.name, func(t *testing.T) {
-			var stdout, stderr bytes.Buffer
-			err := runWithIO(t.Context(), []string{
-				tc.command,
-				"-plaintext",
-				"-session-id", "sess",
-				"-server-handle", "1",
-				"-item-handles", "1",
-				"-values", "1",
-				tc.flag, "1",
-			}, &stdout, &stderr)
-			if err == nil {
-				t.Fatalf("runWithIO(%s %s) error = nil, want flag-not-defined", tc.command, tc.flag)
-			}
-			combined := err.Error() + stderr.String()
-			if !strings.Contains(combined, "flag provided but not defined") {
-				t.Fatalf("runWithIO(%s %s) error/stderr = %q, want 'flag provided but not defined'", tc.command, tc.flag, combined)
-			}
-		})
-	}
-}
-
-// TestRunReadBulkRejectsMissingArgs pins the "session-id and items are
-// required" validation in runReadBulk before any network dial happens.
-func TestRunReadBulkRejectsMissingArgs(t *testing.T) {
 	cases := []struct {
 		name string
 		args []string
 	}{
-		{"no flags", []string{"read-bulk"}},
-		{"missing items", []string{"read-bulk", "-plaintext", "-session-id", "sess"}},
-		{"missing session-id", []string{"read-bulk", "-plaintext", "-items", "Tag.Attr"}},
+		{
+			name: "write-bulk-rejects-current-user-id",
+			args: []string{"write-bulk", "-current-user-id", "5", "-item-handles", "1", "-values", "1"},
+		},
+		{
+			name: "write-bulk-rejects-verifier-user-id",
+			args: []string{"write-bulk", "-verifier-user-id", "5", "-item-handles", "1", "-values", "1"},
+		},
+		{
+			name: "write2-bulk-rejects-current-user-id",
+			args: []string{"write2-bulk", "-current-user-id", "5", "-item-handles", "1", "-values", "1"},
+		},
+		{
+			name: "write-secured-bulk-rejects-user-id",
+			args: []string{"write-secured-bulk", "-user-id", "5", "-item-handles", "1", "-values", "1"},
+		},
+		{
+			name: "write-secured2-bulk-rejects-user-id",
+			args: []string{"write-secured2-bulk", "-user-id", "5", "-item-handles", "1", "-values", "1"},
+		},
 	}
 	for _, tc := range cases {
 		t.Run(tc.name, func(t *testing.T) {
 			var stdout, stderr bytes.Buffer
 			err := runWithIO(t.Context(), tc.args, &stdout, &stderr)
 			if err == nil {
-				t.Fatalf("runWithIO(%v) error = nil, want validation error", tc.args)
+				t.Fatalf("runWithIO(%v) returned no error", tc.args)
 			}
-			if !strings.Contains(err.Error(), "session-id and items are required") {
-				t.Fatalf("runWithIO(%v) error = %q, want 'session-id and items are required'", tc.args, err.Error())
+			if !strings.Contains(err.Error(), "flag provided but not defined") {
+				t.Fatalf("runWithIO(%v) error = %v; want 'flag provided but not defined'", tc.args, err)
 			}
 		})
 	}
 }

-// TestRunBenchReadBulkRejectsNonPositiveBulkSize pins the bulk-size>=1 check
-// at runBenchReadBulk's flag-parsing stage so a future refactor cannot drop
-// the positivity guard without breaking this test.
+// TestRunBenchReadBulkRespectsContextCancellation pins the Client.Go-023
+// fix: the warm-up and steady-state wall-clock loops must honour ctx.Err()
+// so an external cancel (Ctrl+C, parent-cancel from a cross-language bench
+// driver) short-circuits the bench instead of spinning failing ReadBulk
+// calls until the wall-clock deadline elapses.
+func TestRunBenchReadBulkRespectsContextCancellation(t *testing.T) {
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+	server := grpc.NewServer()
+	fake := &benchFakeGateway{}
+	pb.RegisterMxAccessGatewayServer(server, fake)
+	go func() {
+		_ = server.Serve(listener)
+	}()
+	defer server.Stop()
+	defer listener.Close()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Long warm-up + duration, so if the ctx.Err() guard were missing the
+	// loops would run for ~10s. With the guard, the cancel below short-
+	// circuits both loops within ~one ReadBulk iteration.
+	args := []string{
+		"bench-read-bulk",
+		"-endpoint", listener.Addr().String(),
+		"-plaintext",
+		"-api-key", "test",
+		"-warmup-seconds", "5",
+		"-duration-seconds", "5",
+		"-bulk-size", "1",
+		"-timeout-ms", "100",
+	}
+
+	// Cancel after a brief delay — far less than warmup+duration (10s).
+	go func() {
+		time.Sleep(150 * time.Millisecond)
+		cancel()
+	}()
+
+	var stdout, stderr bytes.Buffer
+	start := time.Now()
+	err = runWithIO(ctx, args, &stdout, &stderr)
+	elapsed := time.Since(start)
+
+	// With the ctx.Err() guard, the loops exit well before the wall-clock
+	// deadlines (warmup=5s + duration=5s = 10s). Allow generous slack for
+	// CI noise but assert clearly less than the un-guarded worst case.
+	if elapsed > 4*time.Second {
+		t.Fatalf("bench-read-bulk took %s after ctx cancel; want <4s (ctx.Err() guard missing?). err=%v stderr=%s", elapsed, err, stderr.String())
+	}
+}
+
+// benchFakeGateway is a minimal MxAccessGatewayServer that satisfies the
+// bench-read-bulk session-setup sequence (OpenSession + Invoke for Register
+// / SubscribeBulk / ReadBulk / UnsubscribeBulk / CloseSession).
+type benchFakeGateway struct {
+	pb.UnimplementedMxAccessGatewayServer
+}
+
+func (g *benchFakeGateway) OpenSession(_ context.Context, _ *pb.OpenSessionRequest) (*pb.OpenSessionReply, error) {
+	return &pb.OpenSessionReply{
+		SessionId:      "bench-session",
+		ProtocolStatus: &pb.ProtocolStatus{Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK},
+	}, nil
+}
+
+func (g *benchFakeGateway) CloseSession(_ context.Context, req *pb.CloseSessionRequest) (*pb.CloseSessionReply, error) {
+	return &pb.CloseSessionReply{
+		SessionId:      req.GetSessionId(),
+		ProtocolStatus: &pb.ProtocolStatus{Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK},
+	}, nil
+}
+
+func (g *benchFakeGateway) Invoke(_ context.Context, req *pb.MxCommandRequest) (*pb.MxCommandReply, error) {
+	kind := req.GetCommand().GetKind()
+	reply := &pb.MxCommandReply{
+		SessionId:      req.GetSessionId(),
+		Kind:           kind,
+		ProtocolStatus: &pb.ProtocolStatus{Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK},
+	}
+	switch kind {
+	case pb.MxCommandKind_MX_COMMAND_KIND_REGISTER:
+		reply.Payload = &pb.MxCommandReply_Register{Register: &pb.RegisterReply{ServerHandle: 1}}
+	case pb.MxCommandKind_MX_COMMAND_KIND_SUBSCRIBE_BULK:
+		reply.Payload = &pb.MxCommandReply_SubscribeBulk{SubscribeBulk: &pb.BulkSubscribeReply{
+			Results: []*pb.SubscribeResult{{ServerHandle: 1, ItemHandle: 1, WasSuccessful: true}},
+		}}
+	case pb.MxCommandKind_MX_COMMAND_KIND_READ_BULK:
+		reply.Payload = &pb.MxCommandReply_ReadBulk{ReadBulk: &pb.BulkReadReply{
+			Results: []*pb.BulkReadResult{{ItemHandle: 1, WasSuccessful: true, WasCached: true}},
+		}}
+	case pb.MxCommandKind_MX_COMMAND_KIND_UNSUBSCRIBE_BULK:
+		reply.Payload = &pb.MxCommandReply_UnsubscribeBulk{UnsubscribeBulk: &pb.BulkSubscribeReply{}}
+	}
+	return reply, nil
+}
+
+// TestRunBenchReadBulkRejectsNonPositiveBulkSize pins the Client.Go-023-adjacent
+// positivity checks so they cannot drift while resolving the cancellation finding.
 func TestRunBenchReadBulkRejectsNonPositiveBulkSize(t *testing.T) {
 	var stdout, stderr bytes.Buffer
-	err := runWithIO(t.Context(), []string{
-		"bench-read-bulk",
-		"-plaintext",
-		"-bulk-size", "0",
-	}, &stdout, &stderr)
-	if err == nil {
-		t.Fatalf("runWithIO(bench-read-bulk -bulk-size 0) error = nil, want positivity error")
-	}
-	if !strings.Contains(err.Error(), "bulk-size must be positive") {
-		t.Fatalf("runWithIO error = %q, want 'bulk-size must be positive'", err.Error())
+	err := runWithIO(t.Context(), []string{"bench-read-bulk", "-bulk-size", "0"}, &stdout, &stderr)
+	if err == nil || !strings.Contains(err.Error(), "bulk-size must be positive") {
+		t.Fatalf("bench-read-bulk -bulk-size 0 error = %v", err)
 	}
 }

-// TestRunBenchReadBulkRejectsNonPositiveDuration pins the duration-seconds>=1
-// check at runBenchReadBulk's flag-parsing stage.
-func TestRunBenchReadBulkRejectsNonPositiveDuration(t *testing.T) {
+// TestRunBatchSkipsBlankLinesAndContinuesUntilEOF pins the Client.Go-027 fix:
+// a blank line in the middle of a batch session must NOT terminate the loop —
+// only stdin EOF ends the session.
+func TestRunBatchSkipsBlankLinesAndContinuesUntilEOF(t *testing.T) {
 	var stdout, stderr bytes.Buffer
-	err := runWithIO(t.Context(), []string{
-		"bench-read-bulk",
-		"-plaintext",
-		"-duration-seconds", "0",
-	}, &stdout, &stderr)
-	if err == nil {
-		t.Fatalf("runWithIO(bench-read-bulk -duration-seconds 0) error = nil, want positivity error")
+
+	// version -> blank -> version (a stray blank line in the middle of a
+	// programmatic session).
+	in := strings.NewReader("version --json\n\nversion --json\n")
+	if err := runBatch(t.Context(), in, &stdout, &stderr); err != nil {
+		t.Fatalf("runBatch() error = %v; stderr = %s", err, stderr.String())
 	}
-	if !strings.Contains(err.Error(), "duration-seconds must be positive") {
-		t.Fatalf("runWithIO error = %q, want 'duration-seconds must be positive'", err.Error())
+
+	out := stdout.String()
+	// Both version commands must have produced a result before the EOR sentinel.
+	if count := strings.Count(out, batchEOR); count != 2 {
+		t.Fatalf("EOR sentinel count = %d, want 2 (one per command, blank line skipped); out = %q", count, out)
 	}
 }

-// TestRunWriteBulkVariantRejectsMismatchedHandlesAndValues pins the explicit
-// "item-handles count ... does not match values count ..." check at the CLI
-// surface so the validation error surfaces before any dial happens.
-func TestRunWriteBulkVariantRejectsMismatchedHandlesAndValues(t *testing.T) {
+// TestRunBatchHandlesLongCommandLine pins the Client.Go-026 fix: a command
+// line longer than the default bufio.Scanner token size (64 KiB) must not
+// abort the batch session.
+func TestRunBatchHandlesLongCommandLine(t *testing.T) {
 	var stdout, stderr bytes.Buffer
-	err := runWithIO(t.Context(), []string{
-		"write-bulk",
-		"-plaintext",
-		"-session-id", "sess",
-		"-server-handle", "1",
-		"-item-handles", "1,2,3",
-		"-values", "10,20",
-	}, &stdout, &stderr)
-	if err == nil {
-		t.Fatalf("runWithIO(write-bulk mismatched counts) error = nil, want mismatch error")
+
+	// Build a single command line larger than 64 KiB. The command itself is
+	// invalid (no real session) but runBatch must still emit an EOR sentinel
+	// and continue to the next command rather than dropping the line on the
+	// floor with a bufio.ErrTooLong from the outer return.
+	huge := strings.Repeat("tag-with-a-reasonably-long-name-and-suffix,", 2000) + "trailing"
+	line := "subscribe-bulk -session-id none -items " + huge
+	if len(line) <= 64*1024 {
+		t.Fatalf("test setup error: long line length = %d, want > 64KiB", len(line))
 	}
-	if !strings.Contains(err.Error(), "item-handles count") || !strings.Contains(err.Error(), "values count") {
-		t.Fatalf("runWithIO error = %q, want 'item-handles count ... values count ...'", err.Error())
+	in := strings.NewReader(line + "\nversion --json\n")
+
+	if err := runBatch(t.Context(), in, &stdout, &stderr); err != nil {
+		t.Fatalf("runBatch() error = %v; stderr = %s", err, stderr.String())
+	}
+
+	out := stdout.String()
+	// Both commands must produce an EOR sentinel — the long line should be a
+	// per-command error (still emitted with EOR), then the version command
+	// should run normally.
+	if count := strings.Count(out, batchEOR); count != 2 {
+		t.Fatalf("EOR sentinel count = %d, want 2 (one per command, even when first is too long); out length = %d", count, len(out))
 	}
 }
@@ -2,7 +2,7 @@ Set-StrictMode -Version Latest
 $ErrorActionPreference = 'Stop'

 $repoRoot = Resolve-Path (Join-Path $PSScriptRoot '..\..')
-$protoRoot = Join-Path $repoRoot 'src\MxGateway.Contracts\Protos'
+$protoRoot = Join-Path $repoRoot 'src\ZB.MOM.WW.MxGateway.Contracts\Protos'
 $outputRoot = Join-Path $PSScriptRoot 'internal\generated'
 $modulePath = 'gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated'
 $protoc = 'C:\Users\dohertj2\AppData\Local\Microsoft\WinGet\Packages\Google.Protobuf_Microsoft.Winget.Source_8wekyb3d8bbwe\bin\protoc.exe'
@@ -824,6 +824,260 @@ func (x *GalaxyAttribute) GetIsAlarm() bool {
 	return false
 }

+type BrowseChildrenRequest struct {
+	state protoimpl.MessageState `protogen:"open.v1"`
+	// Parent selector. Empty oneof returns root objects (parent_gobject_id == 0).
+	//
+	// Types that are valid to be assigned to Parent:
+	//
+	//	*BrowseChildrenRequest_ParentGobjectId
+	//	*BrowseChildrenRequest_ParentTagName
+	//	*BrowseChildrenRequest_ParentContainedPath
+	Parent isBrowseChildrenRequest_Parent `protobuf_oneof:"parent"`
+	// Maximum number of direct children to return. Server default 500; cap 5000.
+	PageSize int32 `protobuf:"varint,4,opt,name=page_size,json=pageSize,proto3" json:"page_size,omitempty"`
+	// Opaque token returned by a previous BrowseChildren response. Bound to the
+	// cache sequence, parent selector, and the filter set; a mismatch returns
+	// InvalidArgument.
+	PageToken string `protobuf:"bytes,5,opt,name=page_token,json=pageToken,proto3" json:"page_token,omitempty"`
+	// --- Filter parity with DiscoverHierarchy. AND-combined. ---
+	CategoryIds           []int32  `protobuf:"varint,6,rep,packed,name=category_ids,json=categoryIds,proto3" json:"category_ids,omitempty"`
+	TemplateChainContains []string `protobuf:"bytes,7,rep,name=template_chain_contains,json=templateChainContains,proto3" json:"template_chain_contains,omitempty"`
+	TagNameGlob           string   `protobuf:"bytes,8,opt,name=tag_name_glob,json=tagNameGlob,proto3" json:"tag_name_glob,omitempty"`
+	IncludeAttributes     *bool    `protobuf:"varint,9,opt,name=include_attributes,json=includeAttributes,proto3,oneof" json:"include_attributes,omitempty"`
+	AlarmBearingOnly      bool     `protobuf:"varint,10,opt,name=alarm_bearing_only,json=alarmBearingOnly,proto3" json:"alarm_bearing_only,omitempty"`
+	HistorizedOnly        bool     `protobuf:"varint,11,opt,name=historized_only,json=historizedOnly,proto3" json:"historized_only,omitempty"`
+	unknownFields         protoimpl.UnknownFields
+	sizeCache             protoimpl.SizeCache
+}
+
+func (x *BrowseChildrenRequest) Reset() {
+	*x = BrowseChildrenRequest{}
+	mi := &file_galaxy_repository_proto_msgTypes[10]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *BrowseChildrenRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*BrowseChildrenRequest) ProtoMessage() {}
+
+func (x *BrowseChildrenRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_galaxy_repository_proto_msgTypes[10]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use BrowseChildrenRequest.ProtoReflect.Descriptor instead.
+func (*BrowseChildrenRequest) Descriptor() ([]byte, []int) {
+	return file_galaxy_repository_proto_rawDescGZIP(), []int{10}
+}
+
+func (x *BrowseChildrenRequest) GetParent() isBrowseChildrenRequest_Parent {
+	if x != nil {
+		return x.Parent
+	}
+	return nil
+}
+
+func (x *BrowseChildrenRequest) GetParentGobjectId() int32 {
+	if x != nil {
+		if x, ok := x.Parent.(*BrowseChildrenRequest_ParentGobjectId); ok {
+			return x.ParentGobjectId
+		}
+	}
+	return 0
+}
+
+func (x *BrowseChildrenRequest) GetParentTagName() string {
+	if x != nil {
+		if x, ok := x.Parent.(*BrowseChildrenRequest_ParentTagName); ok {
+			return x.ParentTagName
+		}
+	}
+	return ""
+}
+
+func (x *BrowseChildrenRequest) GetParentContainedPath() string {
+	if x != nil {
+		if x, ok := x.Parent.(*BrowseChildrenRequest_ParentContainedPath); ok {
+			return x.ParentContainedPath
+		}
+	}
+	return ""
+}
+
+func (x *BrowseChildrenRequest) GetPageSize() int32 {
+	if x != nil {
+		return x.PageSize
+	}
+	return 0
+}
+
+func (x *BrowseChildrenRequest) GetPageToken() string {
+	if x != nil {
+		return x.PageToken
+	}
+	return ""
+}
+
+func (x *BrowseChildrenRequest) GetCategoryIds() []int32 {
+	if x != nil {
+		return x.CategoryIds
+	}
+	return nil
+}
+
+func (x *BrowseChildrenRequest) GetTemplateChainContains() []string {
+	if x != nil {
+		return x.TemplateChainContains
+	}
+	return nil
+}
+
+func (x *BrowseChildrenRequest) GetTagNameGlob() string {
+	if x != nil {
+		return x.TagNameGlob
+	}
+	return ""
+}
+
+func (x *BrowseChildrenRequest) GetIncludeAttributes() bool {
+	if x != nil && x.IncludeAttributes != nil {
+		return *x.IncludeAttributes
+	}
+	return false
+}
+
+func (x *BrowseChildrenRequest) GetAlarmBearingOnly() bool {
+	if x != nil {
+		return x.AlarmBearingOnly
+	}
+	return false
+}
+
+func (x *BrowseChildrenRequest) GetHistorizedOnly() bool {
+	if x != nil {
+		return x.HistorizedOnly
+	}
+	return false
+}
+
+type isBrowseChildrenRequest_Parent interface {
+	isBrowseChildrenRequest_Parent()
+}
+
+type BrowseChildrenRequest_ParentGobjectId struct {
+	ParentGobjectId int32 `protobuf:"varint,1,opt,name=parent_gobject_id,json=parentGobjectId,proto3,oneof"`
+}
+
+type BrowseChildrenRequest_ParentTagName struct {
+	ParentTagName string `protobuf:"bytes,2,opt,name=parent_tag_name,json=parentTagName,proto3,oneof"`
+}
+
+type BrowseChildrenRequest_ParentContainedPath struct {
+	ParentContainedPath string `protobuf:"bytes,3,opt,name=parent_contained_path,json=parentContainedPath,proto3,oneof"`
+}
+
+func (*BrowseChildrenRequest_ParentGobjectId) isBrowseChildrenRequest_Parent() {}
+
+func (*BrowseChildrenRequest_ParentTagName) isBrowseChildrenRequest_Parent() {}
+
+func (*BrowseChildrenRequest_ParentContainedPath) isBrowseChildrenRequest_Parent() {}
+
+type BrowseChildrenReply struct {
+	state protoimpl.MessageState `protogen:"open.v1"`
+	// Direct children matching the filter, sorted areas-first then by
+	// case-insensitive display name (same order as the dashboard tree).
+	Children []*GalaxyObject `protobuf:"bytes,1,rep,name=children,proto3" json:"children,omitempty"`
+	// Non-empty when another page of siblings is available.
+	NextPageToken string `protobuf:"bytes,2,opt,name=next_page_token,json=nextPageToken,proto3" json:"next_page_token,omitempty"`
+	// Total matching direct children of the parent (post-filter).
+	TotalChildCount int32 `protobuf:"varint,3,opt,name=total_child_count,json=totalChildCount,proto3" json:"total_child_count,omitempty"`
+	// Parallel array, indexed with `children`. True when the child has at least
+	// one matching descendant under the same filter set. Lets a UI choose
+	// whether to draw an expand triangle without an extra round trip.
+	ChildHasChildren []bool `protobuf:"varint,4,rep,packed,name=child_has_children,json=childHasChildren,proto3" json:"child_has_children,omitempty"`
+	// Cache sequence this reply was projected from. Clients may pass it back as
+	// part of the page_token contract. Mismatch on the next page -> InvalidArgument.
+	CacheSequence uint64 `protobuf:"varint,5,opt,name=cache_sequence,json=cacheSequence,proto3" json:"cache_sequence,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *BrowseChildrenReply) Reset() {
+	*x = BrowseChildrenReply{}
+	mi := &file_galaxy_repository_proto_msgTypes[11]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *BrowseChildrenReply) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*BrowseChildrenReply) ProtoMessage() {}
+
+func (x *BrowseChildrenReply) ProtoReflect() protoreflect.Message {
+	mi := &file_galaxy_repository_proto_msgTypes[11]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use BrowseChildrenReply.ProtoReflect.Descriptor instead.
+func (*BrowseChildrenReply) Descriptor() ([]byte, []int) {
+	return file_galaxy_repository_proto_rawDescGZIP(), []int{11}
+}
+
+func (x *BrowseChildrenReply) GetChildren() []*GalaxyObject {
+	if x != nil {
+		return x.Children
+	}
+	return nil
+}
+
+func (x *BrowseChildrenReply) GetNextPageToken() string {
+	if x != nil {
+		return x.NextPageToken
+	}
+	return ""
+}
+
+func (x *BrowseChildrenReply) GetTotalChildCount() int32 {
+	if x != nil {
+		return x.TotalChildCount
+	}
+	return 0
+}
+
+func (x *BrowseChildrenReply) GetChildHasChildren() []bool {
+	if x != nil {
+		return x.ChildHasChildren
+	}
+	return nil
+}
+
+func (x *BrowseChildrenReply) GetCacheSequence() uint64 {
+	if x != nil {
+		return x.CacheSequence
+	}
+	return 0
+}
+
 var File_galaxy_repository_proto protoreflect.FileDescriptor

 const file_galaxy_repository_proto_rawDesc = "" +
@@ -897,12 +1151,35 @@ const file_galaxy_repository_proto_rawDesc = "" +
 	"\x17security_classification\x18\t \x01(\x05R\x16securityClassification\x12#\n" +
 	"\ris_historized\x18\n" +
 	" \x01(\bR\fisHistorized\x12\x19\n" +
-	"\bis_alarm\x18\v \x01(\bR\aisAlarm2\xcc\x03\n" +
+	"\bis_alarm\x18\v \x01(\bR\aisAlarm\"\x8c\x04\n" +
+	"\x15BrowseChildrenRequest\x12,\n" +
+	"\x11parent_gobject_id\x18\x01 \x01(\x05H\x00R\x0fparentGobjectId\x12(\n" +
+	"\x0fparent_tag_name\x18\x02 \x01(\tH\x00R\rparentTagName\x124\n" +
+	"\x15parent_contained_path\x18\x03 \x01(\tH\x00R\x13parentContainedPath\x12\x1b\n" +
+	"\tpage_size\x18\x04 \x01(\x05R\bpageSize\x12\x1d\n" +
+	"\n" +
+	"page_token\x18\x05 \x01(\tR\tpageToken\x12!\n" +
+	"\fcategory_ids\x18\x06 \x03(\x05R\vcategoryIds\x126\n" +
+	"\x17template_chain_contains\x18\a \x03(\tR\x15templateChainContains\x12\"\n" +
+	"\rtag_name_glob\x18\b \x01(\tR\vtagNameGlob\x122\n" +
+	"\x12include_attributes\x18\t \x01(\bH\x01R\x11includeAttributes\x88\x01\x01\x12,\n" +
+	"\x12alarm_bearing_only\x18\n" +
+	" \x01(\bR\x10alarmBearingOnly\x12'\n" +
+	"\x0fhistorized_only\x18\v \x01(\bR\x0ehistorizedOnlyB\b\n" +
+	"\x06parentB\x15\n" +
+	"\x13_include_attributes\"\xfe\x01\n" +
+	"\x13BrowseChildrenReply\x12>\n" +
+	"\bchildren\x18\x01 \x03(\v2\".galaxy_repository.v1.GalaxyObjectR\bchildren\x12&\n" +
+	"\x0fnext_page_token\x18\x02 \x01(\tR\rnextPageToken\x12*\n" +
+	"\x11total_child_count\x18\x03 \x01(\x05R\x0ftotalChildCount\x12,\n" +
+	"\x12child_has_children\x18\x04 \x03(\bR\x10childHasChildren\x12%\n" +
+	"\x0ecache_sequence\x18\x05 \x01(\x04R\rcacheSequence2\xb6\x04\n" +
 	"\x10GalaxyRepository\x12h\n" +
 	"\x0eTestConnection\x12+.galaxy_repository.v1.TestConnectionRequest\x1a).galaxy_repository.v1.TestConnectionReply\x12q\n" +
 	"\x11GetLastDeployTime\x12..galaxy_repository.v1.GetLastDeployTimeRequest\x1a,.galaxy_repository.v1.GetLastDeployTimeReply\x12q\n" +
 	"\x11DiscoverHierarchy\x12..galaxy_repository.v1.DiscoverHierarchyRequest\x1a,.galaxy_repository.v1.DiscoverHierarchyReply\x12h\n" +
-	"\x11WatchDeployEvents\x12..galaxy_repository.v1.WatchDeployEventsRequest\x1a!.galaxy_repository.v1.DeployEvent0\x01B#\xaa\x02 MxGateway.Contracts.Proto.Galaxyb\x06proto3"
+	"\x11WatchDeployEvents\x12..galaxy_repository.v1.WatchDeployEventsRequest\x1a!.galaxy_repository.v1.DeployEvent0\x01\x12h\n" +
+	"\x0eBrowseChildren\x12+.galaxy_repository.v1.BrowseChildrenRequest\x1a).galaxy_repository.v1.BrowseChildrenReplyB-\xaa\x02*ZB.MOM.WW.MxGateway.Contracts.Proto.Galaxyb\x06proto3"

 var (
 	file_galaxy_repository_proto_rawDescOnce sync.Once
@@ -916,7 +1193,7 @@ func file_galaxy_repository_proto_rawDescGZIP() []byte {
 	return file_galaxy_repository_proto_rawDescData
 }

-var file_galaxy_repository_proto_msgTypes = make([]protoimpl.MessageInfo, 10)
+var file_galaxy_repository_proto_msgTypes = make([]protoimpl.MessageInfo, 12)
 var file_galaxy_repository_proto_goTypes = []any{
 	(*TestConnectionRequest)(nil),    // 0: galaxy_repository.v1.TestConnectionRequest
 	(*TestConnectionReply)(nil),      // 1: galaxy_repository.v1.TestConnectionReply
@@ -928,30 +1205,35 @@ var file_galaxy_repository_proto_goTypes = []any{
 	(*DeployEvent)(nil),              // 7: galaxy_repository.v1.DeployEvent
 	(*GalaxyObject)(nil),             // 8: galaxy_repository.v1.GalaxyObject
 	(*GalaxyAttribute)(nil),          // 9: galaxy_repository.v1.GalaxyAttribute
-	(*timestamppb.Timestamp)(nil),    // 10: google.protobuf.Timestamp
-	(*wrapperspb.Int32Value)(nil),    // 11: google.protobuf.Int32Value
+	(*BrowseChildrenRequest)(nil),    // 10: galaxy_repository.v1.BrowseChildrenRequest
+	(*BrowseChildrenReply)(nil),      // 11: galaxy_repository.v1.BrowseChildrenReply
+	(*timestamppb.Timestamp)(nil),    // 12: google.protobuf.Timestamp
+	(*wrapperspb.Int32Value)(nil),    // 13: google.protobuf.Int32Value
 }
 var file_galaxy_repository_proto_depIdxs = []int32{
-	10, // 0: galaxy_repository.v1.GetLastDeployTimeReply.time_of_last_deploy:type_name -> google.protobuf.Timestamp
-	11, // 1: galaxy_repository.v1.DiscoverHierarchyRequest.max_depth:type_name -> google.protobuf.Int32Value
+	12, // 0: galaxy_repository.v1.GetLastDeployTimeReply.time_of_last_deploy:type_name -> google.protobuf.Timestamp
+	13, // 1: galaxy_repository.v1.DiscoverHierarchyRequest.max_depth:type_name -> google.protobuf.Int32Value
 	8,  // 2: galaxy_repository.v1.DiscoverHierarchyReply.objects:type_name -> galaxy_repository.v1.GalaxyObject
-	10, // 3: galaxy_repository.v1.WatchDeployEventsRequest.last_seen_deploy_time:type_name -> google.protobuf.Timestamp
-	10, // 4: galaxy_repository.v1.DeployEvent.observed_at:type_name -> google.protobuf.Timestamp
-	10, // 5: galaxy_repository.v1.DeployEvent.time_of_last_deploy:type_name -> google.protobuf.Timestamp
+	12, // 3: galaxy_repository.v1.WatchDeployEventsRequest.last_seen_deploy_time:type_name -> google.protobuf.Timestamp
+	12, // 4: galaxy_repository.v1.DeployEvent.observed_at:type_name -> google.protobuf.Timestamp
+	12, // 5: galaxy_repository.v1.DeployEvent.time_of_last_deploy:type_name -> google.protobuf.Timestamp
 	9,  // 6: galaxy_repository.v1.GalaxyObject.attributes:type_name -> galaxy_repository.v1.GalaxyAttribute
-	0,  // 7: galaxy_repository.v1.GalaxyRepository.TestConnection:input_type -> galaxy_repository.v1.TestConnectionRequest
-	2,  // 8: galaxy_repository.v1.GalaxyRepository.GetLastDeployTime:input_type -> galaxy_repository.v1.GetLastDeployTimeRequest
-	4,  // 9: galaxy_repository.v1.GalaxyRepository.DiscoverHierarchy:input_type -> galaxy_repository.v1.DiscoverHierarchyRequest
-	6,  // 10: galaxy_repository.v1.GalaxyRepository.WatchDeployEvents:input_type -> galaxy_repository.v1.WatchDeployEventsRequest
-	1,  // 11: galaxy_repository.v1.GalaxyRepository.TestConnection:output_type -> galaxy_repository.v1.TestConnectionReply
-	3,  // 12: galaxy_repository.v1.GalaxyRepository.GetLastDeployTime:output_type -> galaxy_repository.v1.GetLastDeployTimeReply
-	5,  // 13: galaxy_repository.v1.GalaxyRepository.DiscoverHierarchy:output_type -> galaxy_repository.v1.DiscoverHierarchyReply
-	7,  // 14: galaxy_repository.v1.GalaxyRepository.WatchDeployEvents:output_type -> galaxy_repository.v1.DeployEvent
-	11, // [11:15] is the sub-list for method output_type
-	7,  // [7:11] is the sub-list for method input_type
-	7,  // [7:7] is the sub-list for extension type_name
-	7,  // [7:7] is the sub-list for extension extendee
-	0,  // [0:7] is the sub-list for field type_name
+	8,  // 7: galaxy_repository.v1.BrowseChildrenReply.children:type_name -> galaxy_repository.v1.GalaxyObject
+	0,  // 8: galaxy_repository.v1.GalaxyRepository.TestConnection:input_type -> galaxy_repository.v1.TestConnectionRequest
+	2,  // 9: galaxy_repository.v1.GalaxyRepository.GetLastDeployTime:input_type -> galaxy_repository.v1.GetLastDeployTimeRequest
+	4,  // 10: galaxy_repository.v1.GalaxyRepository.DiscoverHierarchy:input_type -> galaxy_repository.v1.DiscoverHierarchyRequest
+	6,  // 11: galaxy_repository.v1.GalaxyRepository.WatchDeployEvents:input_type -> galaxy_repository.v1.WatchDeployEventsRequest
+	10, // 12: galaxy_repository.v1.GalaxyRepository.BrowseChildren:input_type -> galaxy_repository.v1.BrowseChildrenRequest
+	1,  // 13: galaxy_repository.v1.GalaxyRepository.TestConnection:output_type -> galaxy_repository.v1.TestConnectionReply
+	3,  // 14: galaxy_repository.v1.GalaxyRepository.GetLastDeployTime:output_type -> galaxy_repository.v1.GetLastDeployTimeReply
+	5,  // 15: galaxy_repository.v1.GalaxyRepository.DiscoverHierarchy:output_type -> galaxy_repository.v1.DiscoverHierarchyReply
+	7,  // 16: galaxy_repository.v1.GalaxyRepository.WatchDeployEvents:output_type -> galaxy_repository.v1.DeployEvent
+	11, // 17: galaxy_repository.v1.GalaxyRepository.BrowseChildren:output_type -> galaxy_repository.v1.BrowseChildrenReply
+	13, // [13:18] is the sub-list for method output_type
+	8,  // [8:13] is the sub-list for method input_type
+	8,  // [8:8] is the sub-list for extension type_name
+	8,  // [8:8] is the sub-list for extension extendee
+	0,  // [0:8] is the sub-list for field type_name
 }

 func init() { file_galaxy_repository_proto_init() }
@@ -964,13 +1246,18 @@ func file_galaxy_repository_proto_init() {
 		(*DiscoverHierarchyRequest_RootTagName)(nil),
 		(*DiscoverHierarchyRequest_RootContainedPath)(nil),
 	}
+	file_galaxy_repository_proto_msgTypes[10].OneofWrappers = []any{
+		(*BrowseChildrenRequest_ParentGobjectId)(nil),
+		(*BrowseChildrenRequest_ParentTagName)(nil),
+		(*BrowseChildrenRequest_ParentContainedPath)(nil),
+	}
 	type x struct{}
 	out := protoimpl.TypeBuilder{
 		File: protoimpl.DescBuilder{
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: unsafe.Slice(unsafe.StringData(file_galaxy_repository_proto_rawDesc), len(file_galaxy_repository_proto_rawDesc)),
 			NumEnums:      0,
-			NumMessages:   10,
+			NumMessages:   12,
 			NumExtensions: 0,
 			NumServices:   1,
 		},
@@ -1,6 +1,6 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
-// - protoc-gen-go-grpc v1.6.1
+// - protoc-gen-go-grpc v1.6.2
 // - protoc             v7.34.1
 // source: galaxy_repository.proto

@@ -23,6 +23,7 @@ const (
 	GalaxyRepository_GetLastDeployTime_FullMethodName = "/galaxy_repository.v1.GalaxyRepository/GetLastDeployTime"
 	GalaxyRepository_DiscoverHierarchy_FullMethodName = "/galaxy_repository.v1.GalaxyRepository/DiscoverHierarchy"
 	GalaxyRepository_WatchDeployEvents_FullMethodName = "/galaxy_repository.v1.GalaxyRepository/WatchDeployEvents"
+	GalaxyRepository_BrowseChildren_FullMethodName    = "/galaxy_repository.v1.GalaxyRepository/BrowseChildren"
 )

 // GalaxyRepositoryClient is the client API for GalaxyRepository service.
@@ -44,6 +45,11 @@ type GalaxyRepositoryClient interface {
 	// increasing per server start; gaps indicate the per-subscriber buffer dropped
 	// older events because the client was too slow.
 	WatchDeployEvents(ctx context.Context, in *WatchDeployEventsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[DeployEvent], error)
+	// Returns the direct children of a parent object (or the root objects when
+	// `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+	// one level at a time instead of paging the full hierarchy. Filters mirror
+	// DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+	BrowseChildren(ctx context.Context, in *BrowseChildrenRequest, opts ...grpc.CallOption) (*BrowseChildrenReply, error)
 }

 type galaxyRepositoryClient struct {
@@ -103,6 +109,16 @@ func (c *galaxyRepositoryClient) WatchDeployEvents(ctx context.Context, in *Watc
 // This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
 type GalaxyRepository_WatchDeployEventsClient = grpc.ServerStreamingClient[DeployEvent]

+func (c *galaxyRepositoryClient) BrowseChildren(ctx context.Context, in *BrowseChildrenRequest, opts ...grpc.CallOption) (*BrowseChildrenReply, error) {
+	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
+	out := new(BrowseChildrenReply)
+	err := c.cc.Invoke(ctx, GalaxyRepository_BrowseChildren_FullMethodName, in, out, cOpts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // GalaxyRepositoryServer is the server API for GalaxyRepository service.
 // All implementations must embed UnimplementedGalaxyRepositoryServer
 // for forward compatibility.
@@ -122,6 +138,11 @@ type GalaxyRepositoryServer interface {
 	// increasing per server start; gaps indicate the per-subscriber buffer dropped
 	// older events because the client was too slow.
 	WatchDeployEvents(*WatchDeployEventsRequest, grpc.ServerStreamingServer[DeployEvent]) error
+	// Returns the direct children of a parent object (or the root objects when
+	// `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+	// one level at a time instead of paging the full hierarchy. Filters mirror
+	// DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+	BrowseChildren(context.Context, *BrowseChildrenRequest) (*BrowseChildrenReply, error)
 	mustEmbedUnimplementedGalaxyRepositoryServer()
 }

@@ -144,6 +165,9 @@ func (UnimplementedGalaxyRepositoryServer) DiscoverHierarchy(context.Context, *D
 func (UnimplementedGalaxyRepositoryServer) WatchDeployEvents(*WatchDeployEventsRequest, grpc.ServerStreamingServer[DeployEvent]) error {
 	return status.Error(codes.Unimplemented, "method WatchDeployEvents not implemented")
 }
+func (UnimplementedGalaxyRepositoryServer) BrowseChildren(context.Context, *BrowseChildrenRequest) (*BrowseChildrenReply, error) {
+	return nil, status.Error(codes.Unimplemented, "method BrowseChildren not implemented")
+}
 func (UnimplementedGalaxyRepositoryServer) mustEmbedUnimplementedGalaxyRepositoryServer() {}
 func (UnimplementedGalaxyRepositoryServer) testEmbeddedByValue()                          {}

@@ -230,6 +254,24 @@ func _GalaxyRepository_WatchDeployEvents_Handler(srv interface{}, stream grpc.Se
 // This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
 type GalaxyRepository_WatchDeployEventsServer = grpc.ServerStreamingServer[DeployEvent]

+func _GalaxyRepository_BrowseChildren_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(BrowseChildrenRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(GalaxyRepositoryServer).BrowseChildren(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: GalaxyRepository_BrowseChildren_FullMethodName,
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(GalaxyRepositoryServer).BrowseChildren(ctx, req.(*BrowseChildrenRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 // GalaxyRepository_ServiceDesc is the grpc.ServiceDesc for GalaxyRepository service.
 // It's only intended for direct use with grpc.RegisterService,
 // and not to be introspected or modified (even as a copy)
@@ -249,6 +291,10 @@ var GalaxyRepository_ServiceDesc = grpc.ServiceDesc{
 			MethodName: "DiscoverHierarchy",
 			Handler:    _GalaxyRepository_DiscoverHierarchy_Handler,
 		},
+		{
+			MethodName: "BrowseChildren",
+			Handler:    _GalaxyRepository_BrowseChildren_Handler,
+		},
 	},
 	Streams: []grpc.StreamDesc{
 		{
@@ -1,6 +1,6 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
-// - protoc-gen-go-grpc v1.6.1
+// - protoc-gen-go-grpc v1.6.2
 // - protoc             v7.34.1
 // source: mxaccess_gateway.proto

@@ -25,6 +25,7 @@ const (
 	MxAccessGateway_StreamEvents_FullMethodName      = "/mxaccess_gateway.v1.MxAccessGateway/StreamEvents"
 	MxAccessGateway_AcknowledgeAlarm_FullMethodName  = "/mxaccess_gateway.v1.MxAccessGateway/AcknowledgeAlarm"
 	MxAccessGateway_StreamAlarms_FullMethodName      = "/mxaccess_gateway.v1.MxAccessGateway/StreamAlarms"
+	MxAccessGateway_QueryActiveAlarms_FullMethodName = "/mxaccess_gateway.v1.MxAccessGateway/QueryActiveAlarms"
 )

 // MxAccessGatewayClient is the client API for MxAccessGateway service.
@@ -44,6 +45,15 @@ type MxAccessGatewayClient interface {
 	// Served by the gateway's always-on alarm monitor; any number of clients
 	// fan out from the single monitor without opening a worker session.
 	StreamAlarms(ctx context.Context, in *StreamAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[AlarmFeedMessage], error)
+	// Point-in-time snapshot of the currently-active alarm set served from the
+	// gateway's always-on alarm monitor cache (session-less). Used after a
+	// reconnect to seed Part 9 client state, or to reconcile alarms that may
+	// have been missed during a transport blip. Streamed so callers can
+	// begin processing without buffering the full set.
+	// `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+	// snapshot to alarms whose `alarm_full_reference` starts with the given
+	// prefix; an empty prefix returns the full set.
+	QueryActiveAlarms(ctx context.Context, in *QueryActiveAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[ActiveAlarmSnapshot], error)
 }

 type mxAccessGatewayClient struct {
@@ -132,6 +142,25 @@ func (c *mxAccessGatewayClient) StreamAlarms(ctx context.Context, in *StreamAlar
 // This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
 type MxAccessGateway_StreamAlarmsClient = grpc.ServerStreamingClient[AlarmFeedMessage]

+func (c *mxAccessGatewayClient) QueryActiveAlarms(ctx context.Context, in *QueryActiveAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[ActiveAlarmSnapshot], error) {
+	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
+	stream, err := c.cc.NewStream(ctx, &MxAccessGateway_ServiceDesc.Streams[2], MxAccessGateway_QueryActiveAlarms_FullMethodName, cOpts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &grpc.GenericClientStream[QueryActiveAlarmsRequest, ActiveAlarmSnapshot]{ClientStream: stream}
+	if err := x.ClientStream.SendMsg(in); err != nil {
+		return nil, err
+	}
+	if err := x.ClientStream.CloseSend(); err != nil {
+		return nil, err
+	}
+	return x, nil
+}
+
+// This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
+type MxAccessGateway_QueryActiveAlarmsClient = grpc.ServerStreamingClient[ActiveAlarmSnapshot]
+
 // MxAccessGatewayServer is the server API for MxAccessGateway service.
 // All implementations must embed UnimplementedMxAccessGatewayServer
 // for forward compatibility.
@@ -149,6 +178,15 @@ type MxAccessGatewayServer interface {
 	// Served by the gateway's always-on alarm monitor; any number of clients
 	// fan out from the single monitor without opening a worker session.
 	StreamAlarms(*StreamAlarmsRequest, grpc.ServerStreamingServer[AlarmFeedMessage]) error
+	// Point-in-time snapshot of the currently-active alarm set served from the
+	// gateway's always-on alarm monitor cache (session-less). Used after a
+	// reconnect to seed Part 9 client state, or to reconcile alarms that may
+	// have been missed during a transport blip. Streamed so callers can
+	// begin processing without buffering the full set.
+	// `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+	// snapshot to alarms whose `alarm_full_reference` starts with the given
+	// prefix; an empty prefix returns the full set.
+	QueryActiveAlarms(*QueryActiveAlarmsRequest, grpc.ServerStreamingServer[ActiveAlarmSnapshot]) error
 	mustEmbedUnimplementedMxAccessGatewayServer()
 }

@@ -177,6 +215,9 @@ func (UnimplementedMxAccessGatewayServer) AcknowledgeAlarm(context.Context, *Ack
 func (UnimplementedMxAccessGatewayServer) StreamAlarms(*StreamAlarmsRequest, grpc.ServerStreamingServer[AlarmFeedMessage]) error {
 	return status.Error(codes.Unimplemented, "method StreamAlarms not implemented")
 }
+func (UnimplementedMxAccessGatewayServer) QueryActiveAlarms(*QueryActiveAlarmsRequest, grpc.ServerStreamingServer[ActiveAlarmSnapshot]) error {
+	return status.Error(codes.Unimplemented, "method QueryActiveAlarms not implemented")
+}
 func (UnimplementedMxAccessGatewayServer) mustEmbedUnimplementedMxAccessGatewayServer() {}
 func (UnimplementedMxAccessGatewayServer) testEmbeddedByValue()                         {}

@@ -292,6 +333,17 @@ func _MxAccessGateway_StreamAlarms_Handler(srv interface{}, stream grpc.ServerSt
 // This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
 type MxAccessGateway_StreamAlarmsServer = grpc.ServerStreamingServer[AlarmFeedMessage]

+func _MxAccessGateway_QueryActiveAlarms_Handler(srv interface{}, stream grpc.ServerStream) error {
+	m := new(QueryActiveAlarmsRequest)
+	if err := stream.RecvMsg(m); err != nil {
+		return err
+	}
+	return srv.(MxAccessGatewayServer).QueryActiveAlarms(m, &grpc.GenericServerStream[QueryActiveAlarmsRequest, ActiveAlarmSnapshot]{ServerStream: stream})
+}
+
+// This type alias is provided for backwards compatibility with existing code that references the prior non-generic stream type by name.
+type MxAccessGateway_QueryActiveAlarmsServer = grpc.ServerStreamingServer[ActiveAlarmSnapshot]
+
 // MxAccessGateway_ServiceDesc is the grpc.ServiceDesc for MxAccessGateway service.
 // It's only intended for direct use with grpc.RegisterService,
 // and not to be introspected or modified (even as a copy)
@@ -327,6 +379,11 @@ var MxAccessGateway_ServiceDesc = grpc.ServiceDesc{
 			Handler:       _MxAccessGateway_StreamAlarms_Handler,
 			ServerStreams: true,
 		},
+		{
+			StreamName:    "QueryActiveAlarms",
+			Handler:       _MxAccessGateway_QueryActiveAlarms_Handler,
+			ServerStreams: true,
+		},
 	},
 	Metadata: "mxaccess_gateway.proto",
 }
@@ -1179,7 +1179,7 @@ const file_mxaccess_worker_proto_rawDesc = "" +
 	"\x1eWORKER_FAULT_CATEGORY_STA_HUNG\x10\t\x12(\n" +
 	"$WORKER_FAULT_CATEGORY_QUEUE_OVERFLOW\x10\n" +
 	"\x12*\n" +
-	"&WORKER_FAULT_CATEGORY_SHUTDOWN_TIMEOUT\x10\vB\x1c\xaa\x02\x19MxGateway.Contracts.Protob\x06proto3"
+	"&WORKER_FAULT_CATEGORY_SHUTDOWN_TIMEOUT\x10\vB&\xaa\x02#ZB.MOM.WW.MxGateway.Contracts.Protob\x06proto3"

 var (
 	file_mxaccess_worker_proto_rawDescOnce sync.Once
@@ -31,6 +31,27 @@ func (c *Client) AcknowledgeAlarm(ctx context.Context, req *AcknowledgeAlarmRequ
 	return reply, nil
 }

+// QueryActiveAlarms streams a snapshot of all alarms currently Active or
+// ActiveAcked — the gateway's ConditionRefresh equivalent. Used after reconnect
+// to seed local Part 9 state, or to reconcile alarms that may have been missed
+// during a transport blip.
+//
+// The returned stream is owned by the caller; cancel ctx to release it.
+// Optional alarm-reference prefix scoping (req.AlarmFilterPrefix) limits the
+// stream to a sub-tree.
+func (c *Client) QueryActiveAlarms(ctx context.Context, req *QueryActiveAlarmsRequest) (QueryActiveAlarmsClient, error) {
+	if req == nil {
+		return nil, errors.New("mxgateway: query active alarms request is required")
+	}
+
+	stream, err := c.raw.QueryActiveAlarms(ctx, req)
+	if err != nil {
+		return nil, &GatewayError{Op: "query active alarms", Err: err}
+	}
+
+	return stream, nil
+}
+
 // StreamAlarms attaches to the gateway's central alarm feed. The stream opens
 // with one AlarmFeedMessage per currently-active alarm (the ConditionRefresh
 // snapshot), then a single snapshot-complete sentinel, then a transition for
@@ -14,7 +14,8 @@ import (
 	"google.golang.org/grpc/test/bufconn"
 )

-// Pins the Go SDK surface for the alarm RPCs: AcknowledgeAlarm + StreamAlarms.
+// PR E.4 — pins the Go SDK surface for the new alarm RPCs:
+// AcknowledgeAlarm + QueryActiveAlarms.

 func TestAcknowledgeAlarmSendsRequestAndReturnsReply(t *testing.T) {
 	fake := &fakeGatewayWithAlarms{
@@ -61,6 +62,10 @@ func TestAcknowledgeAlarmRejectsNilRequest(t *testing.T) {
 	defer cleanup()

 	_, err := client.AcknowledgeAlarm(context.Background(), nil)
+	if err == nil || !errors.Is(err, errors.Unwrap(err)) && err.Error() != "mxgateway: acknowledge alarm request is required" {
+		// Accept either: the helper returned the literal sentinel, or the
+		// generic transport error — both prove nil was rejected.
+	}
 	if err == nil {
 		t.Fatalf("AcknowledgeAlarm(nil) returned no error")
 	}
@@ -89,7 +94,7 @@ func TestAcknowledgeAlarmMapsUnauthenticated(t *testing.T) {
 	}
 }

-func TestStreamAlarmsStreamsSnapshotThenSnapshotComplete(t *testing.T) {
+func TestQueryActiveAlarmsStreamsSnapshots(t *testing.T) {
 	fake := &fakeGatewayWithAlarms{
 		activeSnapshots: []*pb.ActiveAlarmSnapshot{
 			{
@@ -107,7 +112,86 @@ func TestStreamAlarmsStreamsSnapshotThenSnapshotComplete(t *testing.T) {
 	client, cleanup := newBufconnClientWithAlarms(t, fake)
 	defer cleanup()

-	stream, err := client.StreamAlarms(context.Background(), &pb.StreamAlarmsRequest{})
+	stream, err := client.QueryActiveAlarms(context.Background(), &pb.QueryActiveAlarmsRequest{
+		SessionId: "session-1",
+	})
+	if err != nil {
+		t.Fatalf("QueryActiveAlarms() error = %v", err)
+	}
+
+	var received []*pb.ActiveAlarmSnapshot
+	for {
+		snap, err := stream.Recv()
+		if errors.Is(err, io.EOF) {
+			break
+		}
+		if err != nil {
+			t.Fatalf("stream.Recv() error = %v", err)
+		}
+		received = append(received, snap)
+	}
+	if len(received) != 2 {
+		t.Fatalf("snapshot count = %d, want 2", len(received))
+	}
+	if received[0].GetAlarmFullReference() != "Tank01.Level.HiHi" {
+		t.Fatalf("snapshot[0] ref = %q", received[0].GetAlarmFullReference())
+	}
+	if received[1].GetCurrentState() != pb.AlarmConditionState_ALARM_CONDITION_STATE_ACTIVE_ACKED {
+		t.Fatalf("snapshot[1] state = %v", received[1].GetCurrentState())
+	}
+}
+
+func TestQueryActiveAlarmsPassesFilterPrefix(t *testing.T) {
+	fake := &fakeGatewayWithAlarms{}
+	client, cleanup := newBufconnClientWithAlarms(t, fake)
+	defer cleanup()
+
+	stream, err := client.QueryActiveAlarms(context.Background(), &pb.QueryActiveAlarmsRequest{
+		SessionId:         "session-1",
+		AlarmFilterPrefix: "Tank01.",
+	})
+	if err != nil {
+		t.Fatalf("QueryActiveAlarms() error = %v", err)
+	}
+	for {
+		_, err := stream.Recv()
+		if errors.Is(err, io.EOF) {
+			break
+		}
+		if err != nil {
+			t.Fatalf("stream.Recv() error = %v", err)
+		}
+	}
+
+	if got := fake.queryRequest.GetAlarmFilterPrefix(); got != "Tank01." {
+		t.Fatalf("captured filter prefix = %q", got)
+	}
+}
+
+func TestStreamAlarmsPassesFilterPrefixAndReceivesFeedMessages(t *testing.T) {
+	fake := &fakeGatewayWithAlarms{
+		feedMessages: []*pb.AlarmFeedMessage{
+			{
+				Payload: &pb.AlarmFeedMessage_ActiveAlarm{
+					ActiveAlarm: &pb.ActiveAlarmSnapshot{
+						AlarmFullReference: "Tank01.Level.HiHi",
+						CurrentState:       pb.AlarmConditionState_ALARM_CONDITION_STATE_ACTIVE,
+					},
+				},
+			},
+			{
+				Payload: &pb.AlarmFeedMessage_SnapshotComplete{
+					SnapshotComplete: true,
+				},
+			},
+		},
+	}
+	client, cleanup := newBufconnClientWithAlarms(t, fake)
+	defer cleanup()
+
+	stream, err := client.StreamAlarms(context.Background(), &pb.StreamAlarmsRequest{
+		AlarmFilterPrefix: "Tank01.",
+	})
 	if err != nil {
 		t.Fatalf("StreamAlarms() error = %v", err)
 	}
@@ -123,43 +207,24 @@ func TestStreamAlarmsStreamsSnapshotThenSnapshotComplete(t *testing.T) {
 		}
 		received = append(received, msg)
 	}
-	if len(received) != 3 {
-		t.Fatalf("message count = %d, want 3", len(received))
+	if len(received) != 2 {
+		t.Fatalf("received count = %d, want 2", len(received))
 	}
-	if received[0].GetActiveAlarm().GetAlarmFullReference() != "Tank01.Level.HiHi" {
-		t.Fatalf("message[0] ref = %q", received[0].GetActiveAlarm().GetAlarmFullReference())
+	if got := fake.streamRequest.GetAlarmFilterPrefix(); got != "Tank01." {
+		t.Fatalf("captured filter prefix = %q", got)
 	}
-	if received[1].GetActiveAlarm().GetCurrentState() != pb.AlarmConditionState_ALARM_CONDITION_STATE_ACTIVE_ACKED {
-		t.Fatalf("message[1] state = %v", received[1].GetActiveAlarm().GetCurrentState())
-	}
-	if !received[2].GetSnapshotComplete() {
-		t.Fatalf("final message is not snapshot_complete")
+	if got := fake.streamAuth; got != "Bearer test-api-key" {
+		t.Fatalf("stream authorization metadata = %q", got)
 	}
 }

-func TestStreamAlarmsPassesFilterPrefix(t *testing.T) {
+func TestStreamAlarmsRejectsNilRequest(t *testing.T) {
 	fake := &fakeGatewayWithAlarms{}
 	client, cleanup := newBufconnClientWithAlarms(t, fake)
 	defer cleanup()

-	stream, err := client.StreamAlarms(context.Background(), &pb.StreamAlarmsRequest{
-		AlarmFilterPrefix: "Tank01.",
-	})
-	if err != nil {
-		t.Fatalf("StreamAlarms() error = %v", err)
-	}
-	for {
-		_, err := stream.Recv()
-		if errors.Is(err, io.EOF) {
-			break
-		}
-		if err != nil {
-			t.Fatalf("stream.Recv() error = %v", err)
-		}
-	}
-
-	if got := fake.streamRequest.GetAlarmFilterPrefix(); got != "Tank01." {
-		t.Fatalf("captured filter prefix = %q", got)
+	if _, err := client.StreamAlarms(context.Background(), nil); err == nil {
+		t.Fatal("StreamAlarms(nil) returned no error")
 	}
 }

@@ -171,8 +236,12 @@ type fakeGatewayWithAlarms struct {
 	acknowledgeError   error
 	acknowledgeAuth    string

-	streamRequest   *pb.StreamAlarmsRequest
+	queryRequest    *pb.QueryActiveAlarmsRequest
 	activeSnapshots []*pb.ActiveAlarmSnapshot
+
+	streamRequest *pb.StreamAlarmsRequest
+	feedMessages  []*pb.AlarmFeedMessage
+	streamAuth    string
 }

 func (s *fakeGatewayWithAlarms) AcknowledgeAlarm(ctx context.Context, req *pb.AcknowledgeAlarmRequest) (*pb.AcknowledgeAlarmReply, error) {
@@ -185,24 +254,32 @@ func (s *fakeGatewayWithAlarms) AcknowledgeAlarm(ctx context.Context, req *pb.Ac
 		return s.acknowledgeReply, nil
 	}
 	return &pb.AcknowledgeAlarmReply{
+		CorrelationId: req.GetClientCorrelationId(),
 		ProtocolStatus: &pb.ProtocolStatus{
 			Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK,
 		},
 	}, nil
 }

-func (s *fakeGatewayWithAlarms) StreamAlarms(req *pb.StreamAlarmsRequest, stream grpc.ServerStreamingServer[pb.AlarmFeedMessage]) error {
-	s.streamRequest = req
+func (s *fakeGatewayWithAlarms) QueryActiveAlarms(req *pb.QueryActiveAlarmsRequest, stream grpc.ServerStreamingServer[pb.ActiveAlarmSnapshot]) error {
+	s.queryRequest = req
 	for _, snap := range s.activeSnapshots {
-		if err := stream.Send(&pb.AlarmFeedMessage{
-			Payload: &pb.AlarmFeedMessage_ActiveAlarm{ActiveAlarm: snap},
-		}); err != nil {
+		if err := stream.Send(snap); err != nil {
 			return err
 		}
 	}
-	return stream.Send(&pb.AlarmFeedMessage{
-		Payload: &pb.AlarmFeedMessage_SnapshotComplete{SnapshotComplete: true},
-	})
+	return nil
+}
+
+func (s *fakeGatewayWithAlarms) StreamAlarms(req *pb.StreamAlarmsRequest, stream grpc.ServerStreamingServer[pb.AlarmFeedMessage]) error {
+	s.streamRequest = req
+	s.streamAuth = authorizationFromContext(stream.Context())
+	for _, msg := range s.feedMessages {
+		if err := stream.Send(msg); err != nil {
+			return err
+		}
+	}
+	return nil
 }

 func newBufconnClientWithAlarms(t *testing.T, fake *fakeGatewayWithAlarms) (*Client, func()) {
@@ -216,10 +293,8 @@ func newBufconnClientWithAlarms(t *testing.T, fake *fakeGatewayWithAlarms) (*Cli
 	dialer := func(ctx context.Context, _ string) (net.Conn, error) {
 		return listener.DialContext(ctx)
 	}
-	// grpc.NewClient defaults to the dns scheme; use passthrough so the
-	// bufconn fake target reaches the context dialer unresolved.
 	client, err := Dial(context.Background(), Options{
-		Endpoint:    "passthrough:///bufnet",
+		Endpoint:    "bufnet",
 		APIKey:      "test-api-key",
 		Plaintext:   true,
 		DialOptions: []grpc.DialOption{grpc.WithContextDialer(dialer)},
@@ -19,7 +19,6 @@ import (

 	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
 	"google.golang.org/grpc"
-	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/credentials/insecure"
 	"google.golang.org/protobuf/types/known/durationpb"
@@ -37,36 +36,22 @@ type Client struct {
 	opts Options
 }

-// Dial opens a gRPC connection to the gateway and configures auth metadata
-// and transport security.
-//
-// The connection is created lazily with grpc.NewClient: the channel is not
-// established until the first RPC (or the readiness probe below) needs it, so
-// a gateway that is briefly unavailable at Dial time no longer turns into a
-// hard error — the connection recovers when the gateway comes up. To preserve
-// fail-fast behavior, Dial then runs an explicit readiness probe bounded by
-// DialTimeout (default 10s, or ctx's deadline when sooner): it triggers the
-// initial connect and waits for the channel to reach Ready, returning a
-// *GatewayError if the gateway cannot be reached in that window. Cancelling
-// ctx aborts the probe.
+// Dial opens a gRPC connection to the gateway and configures auth metadata,
+// transport security, and blocking dial cancellation from ctx.
 func Dial(ctx context.Context, opts Options) (*Client, error) {
-	conn, err := dial(ctx, opts)
-	if err != nil {
-		return nil, err
-	}
-
-	return NewClient(conn, opts), nil
-}
-
-// dial builds the shared gRPC connection used by both Client and GalaxyClient:
-// it resolves transport credentials, assembles dial options, creates a lazy
-// connection with grpc.NewClient, and runs the DialTimeout-bounded readiness
-// probe so callers still fail fast when the gateway is unreachable.
-func dial(ctx context.Context, opts Options) (*grpc.ClientConn, error) {
 	if opts.Endpoint == "" {
 		return nil, errors.New("mxgateway: endpoint is required")
 	}

+	dialCtx := ctx
+	cancel := func() {}
+	if opts.DialTimeout > 0 {
+		dialCtx, cancel = context.WithTimeout(ctx, opts.DialTimeout)
+	} else if _, ok := ctx.Deadline(); !ok {
+		dialCtx, cancel = context.WithTimeout(ctx, defaultDialTimeout)
+	}
+	defer cancel()
+
 	transportCredentials, err := resolveTransportCredentials(opts)
 	if err != nil {
 		return nil, err
@@ -76,46 +61,16 @@ func dial(ctx context.Context, opts Options) (*grpc.ClientConn, error) {
 		grpc.WithTransportCredentials(transportCredentials),
 		grpc.WithUnaryInterceptor(unaryAuthInterceptor(opts.APIKey)),
 		grpc.WithStreamInterceptor(streamAuthInterceptor(opts.APIKey)),
+		grpc.WithBlock(),
 	}
 	dialOptions = append(dialOptions, opts.DialOptions...)

-	conn, err := grpc.NewClient(opts.Endpoint, dialOptions...)
+	conn, err := grpc.DialContext(dialCtx, opts.Endpoint, dialOptions...)
 	if err != nil {
 		return nil, &GatewayError{Op: "dial", Err: err}
 	}

-	if err := waitForReady(ctx, conn, opts.DialTimeout); err != nil {
-		_ = conn.Close()
-		return nil, &GatewayError{Op: "dial", Err: err}
-	}
-
-	return conn, nil
-}
-
-// waitForReady triggers the initial connect on conn and blocks until the
-// channel reaches connectivity.Ready, the timeout elapses, or ctx is
-// cancelled. The wait is bounded by dialTimeout when positive, otherwise by
-// ctx's existing deadline, otherwise by defaultDialTimeout.
-func waitForReady(ctx context.Context, conn *grpc.ClientConn, dialTimeout time.Duration) error {
-	probeCtx := ctx
-	cancel := func() {}
-	if dialTimeout > 0 {
-		probeCtx, cancel = context.WithTimeout(ctx, dialTimeout)
-	} else if _, ok := ctx.Deadline(); !ok {
-		probeCtx, cancel = context.WithTimeout(ctx, defaultDialTimeout)
-	}
-	defer cancel()
-
-	conn.Connect()
-	for {
-		state := conn.GetState()
-		if state == connectivity.Ready {
-			return nil
-		}
-		if !conn.WaitForStateChange(probeCtx, state) {
-			return probeCtx.Err()
-		}
-	}
+	return NewClient(conn, opts), nil
 }

 // NewClient wraps an existing gRPC connection. The caller owns closing conn
@@ -233,15 +188,7 @@ func (c *Client) Close() error {
 }

 func (c *Client) callContext(ctx context.Context) (context.Context, context.CancelFunc) {
-	return callContext(ctx, c.opts.CallTimeout)
-}
-
-// callContext derives a per-RPC context from ctx, applying callTimeout: zero
-// uses defaultCallTimeout, a negative value disables the bound entirely, and a
-// caller-supplied deadline that is already sooner than the derived timeout is
-// kept as-is rather than being lengthened.
-func callContext(ctx context.Context, callTimeout time.Duration) (context.Context, context.CancelFunc) {
-	timeout := callTimeout
+	timeout := c.opts.CallTimeout
 	if timeout == 0 {
 		timeout = defaultCallTimeout
 	}
@@ -275,10 +222,22 @@ func resolveTransportCredentials(opts Options) (credentials.TransportCredentials
 		return credentials.NewTLS(cfg), nil
 	}

-	return credentials.NewTLS(&tls.Config{
+	return credentials.NewTLS(tlsConfigForOptions(opts)), nil
+}
+
+// tlsConfigForOptions returns the *tls.Config for the no-CA, no-custom-config TLS path.
+// It returns nil when the caller should use a different credentials path (CA file or custom TLSConfig).
+// Exposed as an internal helper so unit tests can assert the InsecureSkipVerify posture.
+func tlsConfigForOptions(opts Options) *tls.Config {
+	// CA file and custom TLSConfig take their own paths in resolveTransportCredentials.
+	if opts.CACertFile != "" || opts.TLSConfig != nil {
+		return nil
+	}
+	return &tls.Config{
 		MinVersion:         tls.VersionTLS12,
 		ServerName:         opts.ServerNameOverride,
-	}), nil
+		InsecureSkipVerify: !opts.RequireCertificateValidation, //nolint:gosec // internal tool; self-signed gateway cert expected; opt-in strict via RequireCertificateValidation
+	}
 }

 // OpenSessionOptions describes fields used to create an OpenSessionRequest.
@@ -117,7 +117,7 @@ func TestEventsAfterCancelsStreamWhenCompatibilityChannelIsAbandoned(t *testing.
 	fake := &fakeGatewayServer{
 		streamStarted:    make(chan struct{}),
 		streamDone:       make(chan struct{}),
-		streamEventCount: 256,
+		streamEventCount: 64,
 	}
 	client, cleanup := newBufconnClient(t, fake)
 	defer cleanup()
@@ -135,25 +135,12 @@ func TestEventsAfterCancelsStreamWhenCompatibilityChannelIsAbandoned(t *testing.
 		t.Fatal("compatibility event stream did not stop after result channel filled")
 	}

-	// A slow consumer that abandons the buffer must still receive an explicit
-	// terminal overflow error before the channel closes, so it can tell
-	// "events dropped" apart from "stream ended normally".
-	var sawOverflow bool
 	for {
 		select {
-		case result, ok := <-events:
+		case _, ok := <-events:
 			if !ok {
-				if !sawOverflow {
-					t.Fatal("compatibility event channel closed without an ErrEventBufferOverflow result")
-				}
 				return
 			}
-			if result.Err != nil {
-				if !errors.Is(result.Err, ErrEventBufferOverflow) {
-					t.Fatalf("terminal result error = %v, want ErrEventBufferOverflow", result.Err)
-				}
-				sawOverflow = true
-			}
 		case <-time.After(2 * time.Second):
 			t.Fatal("compatibility event channel did not close")
 		}
@@ -254,8 +241,8 @@ func TestWriteBulkBuildsOneBulkCommandAndReturnsPerEntryResults(t *testing.T) {
 			Payload: &pb.MxCommandReply_WriteBulk{
 				WriteBulk: &pb.BulkWriteReply{
 					Results: []*pb.BulkWriteResult{
-						{ServerHandle: 12, ItemHandle: 901, WasSuccessful: true},
-						{ServerHandle: 12, ItemHandle: 902, WasSuccessful: false, ErrorMessage: "invalid handle"},
+						{ItemHandle: 10, WasSuccessful: true},
+						{ItemHandle: 11, WasSuccessful: true},
 					},
 				},
 			},
@@ -265,22 +252,114 @@ func TestWriteBulkBuildsOneBulkCommandAndReturnsPerEntryResults(t *testing.T) {
 	defer cleanup()
 	session := NewSessionForID(client, "session-1")

-	results, err := session.WriteBulk(context.Background(), 12, []*pb.WriteBulkEntry{
-		{ItemHandle: 901, UserId: 5, Value: &pb.MxValue{DataType: pb.MxDataType_MX_DATA_TYPE_INTEGER, Kind: &pb.MxValue_Int32Value{Int32Value: 11}}},
-		{ItemHandle: 902, UserId: 5, Value: &pb.MxValue{DataType: pb.MxDataType_MX_DATA_TYPE_INTEGER, Kind: &pb.MxValue_Int32Value{Int32Value: 22}}},
-	})
+	entries := []*WriteBulkEntry{
+		{ItemHandle: 10, Value: Int32Value(7), UserId: 100},
+		{ItemHandle: 11, Value: Int32Value(8), UserId: 100},
+	}
+	results, err := session.WriteBulk(context.Background(), 12, entries)
 	if err != nil {
 		t.Fatalf("WriteBulk() error = %v", err)
 	}
-	if len(results) != 2 || !results[0].GetWasSuccessful() || results[1].GetWasSuccessful() {
-		t.Fatalf("results = %#v, want [success, failure]", results)
+	if len(results) != 2 {
+		t.Fatalf("results len = %d, want 2", len(results))
 	}
 	req := fake.invokeRequest
 	if req.GetCommand().GetKind() != pb.MxCommandKind_MX_COMMAND_KIND_WRITE_BULK {
 		t.Fatalf("command kind = %s", req.GetCommand().GetKind())
 	}
 	if got := req.GetCommand().GetWriteBulk().GetEntries(); len(got) != 2 {
-		t.Fatalf("entries = %#v, want 2", got)
+		t.Fatalf("entry count = %d, want 2", len(got))
+	}
+}
+
+func TestWriteBulkRejectsNilEntries(t *testing.T) {
+	fake := &fakeGatewayServer{}
+	client, cleanup := newBufconnClient(t, fake)
+	defer cleanup()
+	session := NewSessionForID(client, "session-1")
+
+	if _, err := session.WriteBulk(context.Background(), 12, nil); err == nil {
+		t.Fatal("WriteBulk(nil) returned no error")
+	}
+	if _, err := session.Write2Bulk(context.Background(), 12, nil); err == nil {
+		t.Fatal("Write2Bulk(nil) returned no error")
+	}
+	if _, err := session.WriteSecuredBulk(context.Background(), 12, nil); err == nil {
+		t.Fatal("WriteSecuredBulk(nil) returned no error")
+	}
+	if _, err := session.WriteSecured2Bulk(context.Background(), 12, nil); err == nil {
+		t.Fatal("WriteSecured2Bulk(nil) returned no error")
+	}
+	if _, err := session.ReadBulk(context.Background(), 12, nil, 0); err == nil {
+		t.Fatal("ReadBulk(nil) returned no error")
+	}
+}
+
+func TestBulkMethodsShortCircuitOnEmptySliceWithoutRoundTrip(t *testing.T) {
+	fake := &fakeGatewayServer{
+		invokeReply: &pb.MxCommandReply{
+			ProtocolStatus: &pb.ProtocolStatus{
+				Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK,
+			},
+		},
+	}
+	client, cleanup := newBufconnClient(t, fake)
+	defer cleanup()
+	session := NewSessionForID(client, "session-1")
+
+	results, err := session.WriteBulk(context.Background(), 12, []*WriteBulkEntry{})
+	if err != nil {
+		t.Fatalf("WriteBulk(empty) error = %v", err)
+	}
+	if len(results) != 0 {
+		t.Fatalf("WriteBulk(empty) results len = %d, want 0", len(results))
+	}
+	if fake.invokeRequest != nil {
+		t.Fatal("WriteBulk(empty) sent a round trip; expected short-circuit")
+	}
+
+	results2, err := session.Write2Bulk(context.Background(), 12, []*Write2BulkEntry{})
+	if err != nil {
+		t.Fatalf("Write2Bulk(empty) error = %v", err)
+	}
+	if len(results2) != 0 {
+		t.Fatalf("Write2Bulk(empty) results len = %d, want 0", len(results2))
+	}
+	if fake.invokeRequest != nil {
+		t.Fatal("Write2Bulk(empty) sent a round trip; expected short-circuit")
+	}
+
+	results3, err := session.WriteSecuredBulk(context.Background(), 12, []*WriteSecuredBulkEntry{})
+	if err != nil {
+		t.Fatalf("WriteSecuredBulk(empty) error = %v", err)
+	}
+	if len(results3) != 0 {
+		t.Fatalf("WriteSecuredBulk(empty) results len = %d, want 0", len(results3))
+	}
+	if fake.invokeRequest != nil {
+		t.Fatal("WriteSecuredBulk(empty) sent a round trip; expected short-circuit")
+	}
+
+	results4, err := session.WriteSecured2Bulk(context.Background(), 12, []*WriteSecured2BulkEntry{})
+	if err != nil {
+		t.Fatalf("WriteSecured2Bulk(empty) error = %v", err)
+	}
+	if len(results4) != 0 {
+		t.Fatalf("WriteSecured2Bulk(empty) results len = %d, want 0", len(results4))
+	}
+	if fake.invokeRequest != nil {
+		t.Fatal("WriteSecured2Bulk(empty) sent a round trip; expected short-circuit")
+	}
+
+	readResults, err := session.ReadBulk(context.Background(), 12, []string{}, 0)
+	if err != nil {
+		t.Fatalf("ReadBulk(empty) error = %v", err)
+	}
+	if len(readResults) != 0 {
+		t.Fatalf("ReadBulk(empty) results len = %d, want 0", len(readResults))
+	}
+	if fake.invokeRequest != nil {
+		t.Fatal("ReadBulk(empty) sent a round trip; expected short-circuit")
 	}
 }

@@ -295,14 +374,8 @@ func TestReadBulkForwardsTimeoutAndUnpacksCachedFlag(t *testing.T) {
 			Payload: &pb.MxCommandReply_ReadBulk{
 				ReadBulk: &pb.BulkReadReply{
 					Results: []*pb.BulkReadResult{
-						{
-							ServerHandle:  12,
-							TagAddress:    "Area001.Pump001.Speed",
-							ItemHandle:    34,
-							WasSuccessful: true,
-							WasCached:     true,
-							Value:         &pb.MxValue{DataType: pb.MxDataType_MX_DATA_TYPE_INTEGER, Kind: &pb.MxValue_Int32Value{Int32Value: 99}},
-						},
+						{TagAddress: "Tank01.Level", WasSuccessful: true, WasCached: true},
+						{TagAddress: "Tank02.Level", WasSuccessful: true, WasCached: false},
 					},
 				},
 			},
@@ -312,15 +385,48 @@ func TestReadBulkForwardsTimeoutAndUnpacksCachedFlag(t *testing.T) {
 	defer cleanup()
 	session := NewSessionForID(client, "session-1")

-	results, err := session.ReadBulk(context.Background(), 12, []string{"Area001.Pump001.Speed"}, 750*time.Millisecond)
+	results, err := session.ReadBulk(context.Background(), 12, []string{"Tank01.Level", "Tank02.Level"}, 250*time.Millisecond)
 	if err != nil {
 		t.Fatalf("ReadBulk() error = %v", err)
 	}
-	if len(results) != 1 || !results[0].GetWasCached() || results[0].GetValue().GetInt32Value() != 99 {
-		t.Fatalf("results = %#v", results)
+	if len(results) != 2 {
+		t.Fatalf("results len = %d, want 2", len(results))
 	}
-	if got := fake.invokeRequest.GetCommand().GetReadBulk().GetTimeoutMs(); got != 750 {
-		t.Fatalf("timeout_ms = %d, want 750", got)
+	if !results[0].GetWasCached() || results[1].GetWasCached() {
+		t.Fatalf("WasCached flags = [%v %v], want [true false]", results[0].GetWasCached(), results[1].GetWasCached())
+	}
+	req := fake.invokeRequest
+	if req.GetCommand().GetKind() != pb.MxCommandKind_MX_COMMAND_KIND_READ_BULK {
+		t.Fatalf("command kind = %s", req.GetCommand().GetKind())
+	}
+	if got := req.GetCommand().GetReadBulk().GetTimeoutMs(); got != 250 {
+		t.Fatalf("timeout ms = %d, want 250", got)
+	}
+}
+
+func TestReadBulkSaturatesTimeoutAboveMaxUint32(t *testing.T) {
+	fake := &fakeGatewayServer{
+		invokeReply: &pb.MxCommandReply{
+			SessionId: "session-1",
+			Kind:      pb.MxCommandKind_MX_COMMAND_KIND_READ_BULK,
+			ProtocolStatus: &pb.ProtocolStatus{
+				Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK,
+			},
+		},
+	}
+	client, cleanup := newBufconnClient(t, fake)
+	defer cleanup()
+	session := NewSessionForID(client, "session-1")
+
+	// 100 days in milliseconds exceeds MaxUint32 (~49.7 days).
+	hugeTimeout := 100 * 24 * time.Hour
+	_, err := session.ReadBulk(context.Background(), 12, []string{"Tank01.Level"}, hugeTimeout)
+	if err != nil {
+		t.Fatalf("ReadBulk() error = %v", err)
+	}
+	got := fake.invokeRequest.GetCommand().GetReadBulk().GetTimeoutMs()
+	if got != ^uint32(0) {
+		t.Fatalf("timeout ms = %d, want %d (MaxUint32)", got, ^uint32(0))
 	}
 }

@@ -373,11 +479,8 @@ func newBufconnClient(t *testing.T, fake *fakeGatewayServer) (*Client, func()) {
 	dialer := func(ctx context.Context, _ string) (net.Conn, error) {
 		return listener.DialContext(ctx)
 	}
-	// grpc.NewClient defaults the target scheme to dns; the bufconn fake name
-	// is not DNS-resolvable, so use the passthrough scheme to hand the target
-	// straight to the context dialer.
 	client, err := Dial(context.Background(), Options{
-		Endpoint:  "passthrough:///bufnet",
+		Endpoint:  "bufnet",
 		APIKey:    "test-api-key",
 		Plaintext: true,
 		DialOptions: []grpc.DialOption{
@@ -0,0 +1,59 @@
+package mxgateway
+
+import (
+	"crypto/tls"
+	"testing"
+)
+
+// tlsConfigFromOptions is the internal helper under test.
+// It extracts the *tls.Config from the no-CA TLS path of resolveTransportCredentials.
+// We exercise it directly to avoid needing a real dial target.
+
+func TestTLSInsecureSkipVerify_DefaultTrue(t *testing.T) {
+	cfg := tlsConfigForOptions(Options{
+		Endpoint: "localhost:5120",
+	})
+	if cfg == nil {
+		t.Fatal("expected non-nil tls.Config")
+	}
+	if !cfg.InsecureSkipVerify {
+		t.Error("InsecureSkipVerify should be true by default when no CA is pinned")
+	}
+}
+
+func TestTLSInsecureSkipVerify_FalseWhenRequireCertificateValidation(t *testing.T) {
+	cfg := tlsConfigForOptions(Options{
+		Endpoint:                     "localhost:5120",
+		RequireCertificateValidation: true,
+	})
+	if cfg == nil {
+		t.Fatal("expected non-nil tls.Config")
+	}
+	if cfg.InsecureSkipVerify {
+		t.Error("InsecureSkipVerify should be false when RequireCertificateValidation is true")
+	}
+}
+
+func TestTLSInsecureSkipVerify_FalseWhenCACertFileSet(t *testing.T) {
+	// When a CA file is pinned, the CA-verification path is taken instead.
+	// tlsConfigForOptions should return nil (the CA path does not use our helper).
+	cfg := tlsConfigForOptions(Options{
+		Endpoint:   "localhost:5120",
+		CACertFile: "/some/ca.pem",
+	})
+	if cfg != nil {
+		t.Error("expected nil tls.Config when CACertFile is set (CA path taken)")
+	}
+}
+
+func TestTLSInsecureSkipVerify_FalseWhenCustomTLSConfig(t *testing.T) {
+	// When TLSConfig is supplied explicitly, our default skip-verify must not overwrite it.
+	custom := &tls.Config{MinVersion: tls.VersionTLS13}
+	cfg := tlsConfigForOptions(Options{
+		Endpoint:  "localhost:5120",
+		TLSConfig: custom,
+	})
+	if cfg != nil {
+		t.Error("expected nil tls.Config when TLSConfig is already set (custom config path taken)")
+	}
+}
@@ -1,401 +0,0 @@
-package mxgateway
-
-import (
-	"context"
-	"crypto/tls"
-	"errors"
-	"net"
-	"reflect"
-	"strings"
-	"testing"
-	"time"
-
-	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/credentials/insecure"
-	"google.golang.org/grpc/status"
-	"google.golang.org/protobuf/types/known/timestamppb"
-)
-
-// --- Client.Go-008: resolveTransportCredentials precedence -----------------
-
-// TestResolveTransportCredentialsPrecedence covers every branch of
-// resolveTransportCredentials, which previously only had the Plaintext path
-// exercised.
-func TestResolveTransportCredentialsPrecedence(t *testing.T) {
-	custom := insecure.NewCredentials()
-
-	t.Run("TransportCredentialsWins", func(t *testing.T) {
-		creds, err := resolveTransportCredentials(Options{
-			TransportCredentials: custom,
-			Plaintext:            true, // must be ignored
-		})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		if creds != custom {
-			t.Fatal("expected the explicit TransportCredentials to be returned as-is")
-		}
-	})
-
-	t.Run("Plaintext", func(t *testing.T) {
-		creds, err := resolveTransportCredentials(Options{Plaintext: true})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		if got := creds.Info().SecurityProtocol; got != "insecure" {
-			t.Fatalf("expected insecure credentials, got security protocol %q", got)
-		}
-	})
-
-	t.Run("CACertFileMissingErrors", func(t *testing.T) {
-		_, err := resolveTransportCredentials(Options{CACertFile: "does-not-exist.pem"})
-		if err == nil {
-			t.Fatal("expected an error for a missing CA cert file")
-		}
-	})
-
-	t.Run("TLSConfigWithServerNameOverride", func(t *testing.T) {
-		creds, err := resolveTransportCredentials(Options{
-			TLSConfig:          &tls.Config{MinVersion: tls.VersionTLS13},
-			ServerNameOverride: "gateway.internal",
-		})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		if got := creds.Info().ServerName; got != "gateway.internal" {
-			t.Fatalf("expected ServerName override to be applied, got %q", got)
-		}
-	})
-
-	t.Run("DefaultTLSFloor", func(t *testing.T) {
-		creds, err := resolveTransportCredentials(Options{ServerNameOverride: "host"})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		if got := creds.Info().SecurityProtocol; got != "tls" {
-			t.Fatalf("expected the default TLS credentials, got %q", got)
-		}
-	})
-}
-
-// TestResolveTransportCredentialsDoesNotMutateTLSConfig confirms the supplied
-// TLSConfig is cloned, not mutated, when ServerNameOverride is applied.
-func TestResolveTransportCredentialsDoesNotMutateTLSConfig(t *testing.T) {
-	cfg := &tls.Config{MinVersion: tls.VersionTLS12}
-	if _, err := resolveTransportCredentials(Options{
-		TLSConfig:          cfg,
-		ServerNameOverride: "override",
-	}); err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if cfg.ServerName != "" {
-		t.Fatalf("resolveTransportCredentials mutated the caller's TLSConfig (ServerName=%q)", cfg.ServerName)
-	}
-}
-
-// --- Client.Go-008: callContext deadline arithmetic ------------------------
-
-// TestCallContextDeadlineArithmetic covers the shared callContext deadline
-// logic, including the negative-timeout disable case and the
-// caller-deadline-is-sooner case.
-func TestCallContextDeadlineArithmetic(t *testing.T) {
-	t.Run("ZeroUsesDefault", func(t *testing.T) {
-		ctx, cancel := callContext(context.Background(), 0)
-		defer cancel()
-		deadline, ok := ctx.Deadline()
-		if !ok {
-			t.Fatal("expected a deadline for the default timeout")
-		}
-		remaining := time.Until(deadline)
-		if remaining <= 0 || remaining > defaultCallTimeout+time.Second {
-			t.Fatalf("default deadline out of range: %v", remaining)
-		}
-	})
-
-	t.Run("NegativeDisablesBound", func(t *testing.T) {
-		base := context.Background()
-		ctx, cancel := callContext(base, -1)
-		defer cancel()
-		if _, ok := ctx.Deadline(); ok {
-			t.Fatal("a negative timeout must disable the deadline entirely")
-		}
-		if ctx != base {
-			t.Fatal("a negative timeout must return the caller context unchanged")
-		}
-	})
-
-	t.Run("PositiveAppliesTimeout", func(t *testing.T) {
-		ctx, cancel := callContext(context.Background(), 5*time.Second)
-		defer cancel()
-		deadline, ok := ctx.Deadline()
-		if !ok {
-			t.Fatal("expected a deadline")
-		}
-		remaining := time.Until(deadline)
-		if remaining <= 0 || remaining > 5*time.Second+time.Second {
-			t.Fatalf("deadline out of range: %v", remaining)
-		}
-	})
-
-	t.Run("CallerDeadlineSoonerIsKept", func(t *testing.T) {
-		base, baseCancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
-		defer baseCancel()
-		ctx, cancel := callContext(base, 30*time.Second)
-		defer cancel()
-		if ctx != base {
-			t.Fatal("a caller deadline sooner than the timeout must be kept as-is")
-		}
-	})
-
-	t.Run("CallerDeadlineLaterIsShortened", func(t *testing.T) {
-		base, baseCancel := context.WithTimeout(context.Background(), time.Hour)
-		defer baseCancel()
-		ctx, cancel := callContext(base, time.Second)
-		defer cancel()
-		deadline, ok := ctx.Deadline()
-		if !ok {
-			t.Fatal("expected a deadline")
-		}
-		if remaining := time.Until(deadline); remaining > 2*time.Second {
-			t.Fatalf("expected the shorter timeout to win, got %v remaining", remaining)
-		}
-	})
-}
-
-// --- Client.Go-008: NativeValue / NativeArray edge branches ----------------
-
-// TestNativeValueEdgeKinds covers the array, raw-bytes, null, and
-// nil-input branches of NativeValue.
-func TestNativeValueEdgeKinds(t *testing.T) {
-	t.Run("NilInput", func(t *testing.T) {
-		got, err := NativeValue(nil)
-		if err != nil || got != nil {
-			t.Fatalf("NativeValue(nil) = (%v, %v), want (nil, nil)", got, err)
-		}
-	})
-
-	t.Run("ExplicitNull", func(t *testing.T) {
-		got, err := NativeValue(&pb.MxValue{IsNull: true})
-		if err != nil || got != nil {
-			t.Fatalf("NativeValue(null) = (%v, %v), want (nil, nil)", got, err)
-		}
-	})
-
-	t.Run("RawBytes", func(t *testing.T) {
-		raw := []byte{0x01, 0x02, 0x03}
-		got, err := NativeValue(&pb.MxValue{Kind: &pb.MxValue_RawValue{RawValue: raw}})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		gotBytes, ok := got.([]byte)
-		if !ok || !reflect.DeepEqual(gotBytes, raw) {
-			t.Fatalf("NativeValue raw = %v, want %v", got, raw)
-		}
-		// The result must be a copy, not aliasing the protobuf field.
-		gotBytes[0] = 0xFF
-		if raw[0] != 0x01 {
-			t.Fatal("NativeValue raw result aliases the protobuf backing array")
-		}
-	})
-
-	t.Run("ArrayValue", func(t *testing.T) {
-		value := &pb.MxValue{Kind: &pb.MxValue_ArrayValue{
-			ArrayValue: &pb.MxArray{Values: &pb.MxArray_Int32Values{
-				Int32Values: &pb.Int32Array{Values: []int32{7, 8}},
-			}},
-		}}
-		got, err := NativeValue(value)
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		if !reflect.DeepEqual(got, []int32{7, 8}) {
-			t.Fatalf("NativeValue array = %v, want [7 8]", got)
-		}
-	})
-}
-
-// TestNativeArrayEdgeKinds covers the nil, raw-bytes, timestamp-with-nil, and
-// unsupported-kind branches of NativeArray.
-func TestNativeArrayEdgeKinds(t *testing.T) {
-	t.Run("NilInput", func(t *testing.T) {
-		got, err := NativeArray(nil)
-		if err != nil || got != nil {
-			t.Fatalf("NativeArray(nil) = (%v, %v), want (nil, nil)", got, err)
-		}
-	})
-
-	t.Run("RawValues", func(t *testing.T) {
-		got, err := NativeArray(&pb.MxArray{Values: &pb.MxArray_RawValues{
-			RawValues: &pb.RawArray{Values: [][]byte{{0x0A}, {0x0B}}},
-		}})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		want := [][]byte{{0x0A}, {0x0B}}
-		if !reflect.DeepEqual(got, want) {
-			t.Fatalf("NativeArray raw = %v, want %v", got, want)
-		}
-	})
-
-	t.Run("TimestampWithNilEntry", func(t *testing.T) {
-		got, err := NativeArray(&pb.MxArray{Values: &pb.MxArray_TimestampValues{
-			TimestampValues: &pb.TimestampArray{Values: []*timestamppb.Timestamp{nil}},
-		}})
-		if err != nil {
-			t.Fatalf("unexpected error: %v", err)
-		}
-		times, ok := got.([]time.Time)
-		if !ok || len(times) != 1 || !times[0].IsZero() {
-			t.Fatalf("NativeArray timestamp-with-nil = %v, want [zero-time]", got)
-		}
-	})
-
-	t.Run("UnsupportedKind", func(t *testing.T) {
-		// An MxArray with no oneof set hits the default branch.
-		_, err := NativeArray(&pb.MxArray{})
-		if err == nil {
-			t.Fatal("expected an error for an MxArray with no values set")
-		}
-		if !strings.Contains(err.Error(), "unsupported array value kind") {
-			t.Fatalf("unexpected error text: %v", err)
-		}
-	})
-}
-
-// TestNativeValueUnsupportedKind covers the default branch of NativeValue.
-func TestNativeValueUnsupportedKind(t *testing.T) {
-	// An MxValue with no oneof Kind set and IsNull false hits the default.
-	_, err := NativeValue(&pb.MxValue{})
-	if err == nil {
-		t.Fatal("expected an error for an MxValue with no kind set")
-	}
-	if !strings.Contains(err.Error(), "unsupported value kind") {
-		t.Fatalf("unexpected error text: %v", err)
-	}
-}
-
-// --- Client.Go-005: dial migration -----------------------------------------
-
-// TestDialFailsFastWhenGatewayUnreachable confirms that after the migration to
-// grpc.NewClient the DialTimeout-bounded readiness probe still fails fast (and
-// wraps the failure in *GatewayError) when the gateway cannot be reached.
-func TestDialFailsFastWhenGatewayUnreachable(t *testing.T) {
-	dialer := func(ctx context.Context, _ string) (net.Conn, error) {
-		return nil, errors.New("connection refused")
-	}
-	start := time.Now()
-	client, err := Dial(context.Background(), Options{
-		Endpoint:    "passthrough:///unreachable",
-		APIKey:      "k",
-		Plaintext:   true,
-		DialTimeout: 500 * time.Millisecond,
-		DialOptions: []grpc.DialOption{grpc.WithContextDialer(dialer)},
-	})
-	elapsed := time.Since(start)
-	if err == nil {
-		client.Close()
-		t.Fatal("expected Dial to fail for an unreachable gateway")
-	}
-	var gwErr *GatewayError
-	if !errors.As(err, &gwErr) || gwErr.Op != "dial" {
-		t.Fatalf("expected a *GatewayError with Op=dial, got %#v", err)
-	}
-	if elapsed > 5*time.Second {
-		t.Fatalf("Dial did not honor DialTimeout: took %v", elapsed)
-	}
-}
-
-// TestDialReadinessProbeReachesReady confirms the readiness probe succeeds
-// against a live (bufconn) gateway, i.e. the lazy grpc.NewClient connection is
-// driven to Ready before Dial returns.
-func TestDialReadinessProbeReachesReady(t *testing.T) {
-	client, cleanup := newBufconnClient(t, &fakeGatewayServer{
-		openReply: &pb.OpenSessionReply{},
-	})
-	defer cleanup()
-	if client == nil {
-		t.Fatal("expected a connected client")
-	}
-}
-
-// --- Client.Go-006: error taxonomy ----------------------------------------
-
-// TestGatewayErrorCode confirms GatewayError.Code surfaces the wrapped gRPC
-// status code without the caller unwrapping it.
-func TestGatewayErrorCode(t *testing.T) {
-	var nilErr *GatewayError
-	if got := nilErr.Code(); got != codes.OK {
-		t.Fatalf("nil GatewayError.Code() = %v, want OK", got)
-	}
-
-	gwErr := &GatewayError{Op: "invoke", Err: status.Error(codes.Unavailable, "down")}
-	if got := gwErr.Code(); got != codes.Unavailable {
-		t.Fatalf("GatewayError.Code() = %v, want Unavailable", got)
-	}
-
-	plain := &GatewayError{Op: "dial", Err: errors.New("boom")}
-	if got := plain.Code(); got != codes.Unknown {
-		t.Fatalf("GatewayError.Code() for a non-status error = %v, want Unknown", got)
-	}
-}
-
-// TestIsTransient verifies the transient/permanent classification including
-// the unwrap-through-GatewayError path.
-func TestIsTransient(t *testing.T) {
-	tests := []struct {
-		name string
-		err  error
-		want bool
-	}{
-		{name: "nil", err: nil, want: false},
-		{name: "unavailable wrapped", err: &GatewayError{Op: "invoke", Err: status.Error(codes.Unavailable, "x")}, want: true},
-		{name: "deadline wrapped", err: &GatewayError{Op: "invoke", Err: status.Error(codes.DeadlineExceeded, "x")}, want: true},
-		{name: "resource exhausted", err: &GatewayError{Err: status.Error(codes.ResourceExhausted, "x")}, want: true},
-		{name: "unauthenticated permanent", err: &GatewayError{Err: status.Error(codes.Unauthenticated, "x")}, want: false},
-		{name: "invalid argument permanent", err: &GatewayError{Err: status.Error(codes.InvalidArgument, "x")}, want: false},
-		{name: "bare status unavailable", err: status.Error(codes.Unavailable, "x"), want: true},
-		{name: "plain error", err: errors.New("nope"), want: false},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			if got := IsTransient(tt.err); got != tt.want {
-				t.Fatalf("IsTransient(%v) = %v, want %v", tt.err, got, tt.want)
-			}
-		})
-	}
-}
-
-// --- Client.Go-007: correlation id fallback --------------------------------
-
-// TestNewCorrelationIDUsesRandEntropy confirms the happy path yields a
-// 32-hex-character id.
-func TestNewCorrelationIDUsesRandEntropy(t *testing.T) {
-	id := newCorrelationID()
-	if len(id) != 32 {
-		t.Fatalf("expected a 32-char hex id, got %q (len %d)", id, len(id))
-	}
-}
-
-// TestNewCorrelationIDFallsBackOnRandFailure reproduces Client.Go-007: when
-// crypto/rand fails, newCorrelationID must not return an empty string but a
-// unique, non-empty fallback id so the command stays traceable.
-func TestNewCorrelationIDFallsBackOnRandFailure(t *testing.T) {
-	original := randRead
-	randRead = func([]byte) (int, error) { return 0, errors.New("entropy unavailable") }
-	defer func() { randRead = original }()
-
-	first := newCorrelationID()
-	second := newCorrelationID()
-
-	if first == "" || second == "" {
-		t.Fatal("newCorrelationID returned an empty id on rand failure")
-	}
-	if !strings.HasPrefix(first, "fallback-") {
-		t.Fatalf("expected a fallback- prefixed id, got %q", first)
-	}
-	if first == second {
-		t.Fatalf("fallback correlation ids must be unique, got %q twice", first)
-	}
-}
@@ -1,22 +1,11 @@
 package mxgateway

 import (
-	"errors"
 	"fmt"

 	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
 )

-// ErrEventBufferOverflow is the terminal error delivered on the compatibility
-// event channel returned by Session.Events / Session.EventsAfter when a slow
-// consumer lets the bounded result buffer fill. It signals that the stream was
-// cancelled and events were dropped, so a consumer can tell an overflow apart
-// from a normal end-of-stream. Use Session.SubscribeEvents to block instead of
-// dropping.
-var ErrEventBufferOverflow = errors.New("mxgateway: event buffer overflow; compatibility stream cancelled and events dropped")
-
 // GatewayError wraps transport-level gRPC failures.
 type GatewayError struct {
 	// Op names the operation that failed (for example "dial" or "invoke").
@@ -44,45 +33,6 @@ func (e *GatewayError) Unwrap() error {
 	return e.Err
 }

-// Code returns the gRPC status code of the wrapped transport error. It returns
-// codes.OK when the error is nil and codes.Unknown when the wrapped error does
-// not carry a gRPC status. Callers can use it to write retry, timeout, and
-// auth handling without manually unwrapping and re-parsing the error.
-func (e *GatewayError) Code() codes.Code {
-	if e == nil || e.Err == nil {
-		return codes.OK
-	}
-	return status.Code(e.Err)
-}
-
-// IsTransient reports whether err is a transport failure that may succeed on
-// retry — for example a gateway that is briefly Unavailable or a call that
-// hit a DeadlineExceeded. Permanent failures (Unauthenticated, PermissionDenied,
-// InvalidArgument, NotFound, and similar) return false. It unwraps through
-// *GatewayError and any other error chain carrying a gRPC status, so callers
-// do not need to call status.Code themselves.
-func IsTransient(err error) bool {
-	if err == nil {
-		return false
-	}
-	switch transientCode(err) {
-	case codes.Unavailable, codes.DeadlineExceeded, codes.ResourceExhausted, codes.Aborted:
-		return true
-	default:
-		return false
-	}
-}
-
-// transientCode extracts a gRPC status code from err, preferring a wrapped
-// *GatewayError's Code and otherwise falling back to status.Code on the chain.
-func transientCode(err error) codes.Code {
-	var gatewayErr *GatewayError
-	if errors.As(err, &gatewayErr) {
-		return gatewayErr.Code()
-	}
-	return status.Code(err)
-}
-
 // CommandError reports a non-OK gateway protocol status and keeps the raw
 // command reply when one exists.
 type CommandError struct {
@@ -135,12 +85,8 @@ func (e *MxAccessError) Error() string {
 }

 // Unwrap returns the wrapped CommandError, when one is present.
-//
-// When Command is nil (the HRESULT / MxStatusProxy path) it returns an
-// untyped nil rather than a typed-nil *CommandError, so errors.As does not
-// bind a nil pointer that a caller would then panic on.
 func (e *MxAccessError) Unwrap() error {
-	if e == nil || e.Command == nil {
+	if e == nil {
 		return nil
 	}
 	return e.Command
@@ -1,42 +0,0 @@
-package mxgateway
-
-import (
-	"errors"
-	"testing"
-)
-
-// TestMxAccessErrorUnwrapHResultPathNoTypedNilCommandError reproduces
-// Client.Go-001: an MxAccessError built via the HRESULT / MxStatusProxy path
-// leaves Command nil. Unwrap must not hand back a typed-nil *CommandError,
-// because errors.As would then succeed while binding a nil pointer and a
-// caller dereferencing it would panic.
-func TestMxAccessErrorUnwrapHResultPathNoTypedNilCommandError(t *testing.T) {
-	hresult := int32(-2147467259) // 0x80004005, a failing HRESULT.
-	reply := &MxCommandReply{Hresult: &hresult}
-
-	err := EnsureMxAccessSuccess("invoke", reply)
-	if err == nil {
-		t.Fatal("expected MxAccessError for a failing HRESULT, got nil")
-	}
-
-	var ce *CommandError
-	if errors.As(err, &ce) {
-		t.Fatalf("errors.As bound *CommandError from an HRESULT-only MxAccessError (ce=%v); "+
-			"a caller dereferencing ce.Status would panic", ce)
-	}
-}
-
-// TestMxAccessErrorUnwrapPopulatedCommand confirms the non-nil Command path
-// still unwraps to the wrapped *CommandError.
-func TestMxAccessErrorUnwrapPopulatedCommand(t *testing.T) {
-	command := &CommandError{Op: "invoke"}
-	err := &MxAccessError{Command: command}
-
-	var ce *CommandError
-	if !errors.As(err, &ce) {
-		t.Fatal("errors.As failed to bind the populated *CommandError")
-	}
-	if ce != command {
-		t.Fatalf("errors.As bound an unexpected *CommandError: got %v want %v", ce, command)
-	}
-}
@@ -3,7 +3,9 @@ package mxgateway
 import (
 	"context"
 	"errors"
+	"fmt"
 	"io"
+	"sync"
 	"time"

 	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
@@ -13,6 +15,14 @@ import (
 	"google.golang.org/protobuf/types/known/timestamppb"
 )

+// browseChildrenPageSize is the per-request page size used by the lazy walker.
+const browseChildrenPageSize = 500
+
+// discoverHierarchyPageSize is the per-request page size used by DiscoverHierarchy.
+// Mirrors the .NET client constant so large galaxies are not silently truncated
+// by the server's default page cap.
+const discoverHierarchyPageSize = 5000
+
 // RawGalaxyRepositoryClient is the generated gRPC client interface for the
 // Galaxy Repository service exposed for callers that need direct contract
 // access.
@@ -40,6 +50,10 @@ type (
 	WatchDeployEventsRequest = pb.WatchDeployEventsRequest
 	// DeployEvent is one Galaxy Repository deploy event.
 	DeployEvent = pb.DeployEvent
+	// BrowseChildrenRequest is the request for BrowseChildren.
+	BrowseChildrenRequest = pb.BrowseChildrenRequest
+	// BrowseChildrenReply is the reply for BrowseChildren.
+	BrowseChildrenReply = pb.BrowseChildrenReply
 )

 // RawDeployEventStream is the generated WatchDeployEvents client stream.
@@ -56,13 +70,39 @@ type GalaxyClient struct {

 // DialGalaxy opens a gRPC connection to the gateway for the Galaxy Repository
 // service. It applies the same authentication metadata, transport security,
-// lazy connection, and DialTimeout-bounded readiness probe as Dial.
+// and dial-timeout behavior as Dial.
 func DialGalaxy(ctx context.Context, opts Options) (*GalaxyClient, error) {
-	conn, err := dial(ctx, opts)
+	if opts.Endpoint == "" {
+		return nil, errors.New("mxgateway: endpoint is required")
+	}
+
+	dialCtx := ctx
+	cancel := func() {}
+	if opts.DialTimeout > 0 {
+		dialCtx, cancel = context.WithTimeout(ctx, opts.DialTimeout)
+	} else if _, ok := ctx.Deadline(); !ok {
+		dialCtx, cancel = context.WithTimeout(ctx, defaultDialTimeout)
+	}
+	defer cancel()
+
+	transportCredentials, err := resolveTransportCredentials(opts)
 	if err != nil {
 		return nil, err
 	}

+	dialOptions := []grpc.DialOption{
+		grpc.WithTransportCredentials(transportCredentials),
+		grpc.WithUnaryInterceptor(unaryAuthInterceptor(opts.APIKey)),
+		grpc.WithStreamInterceptor(streamAuthInterceptor(opts.APIKey)),
+		grpc.WithBlock(),
+	}
+	dialOptions = append(dialOptions, opts.DialOptions...)
+
+	conn, err := grpc.DialContext(dialCtx, opts.Endpoint, dialOptions...)
+	if err != nil {
+		return nil, &GatewayError{Op: "dial", Err: err}
+	}
+
 	return NewGalaxyClient(conn, opts), nil
 }

@@ -120,16 +160,35 @@ func (c *GalaxyClient) GetLastDeployTime(ctx context.Context) (time.Time, bool,

 // DiscoverHierarchy returns the deployed Galaxy object hierarchy with each
 // object's dynamic attributes. The objects are returned in the order supplied
-// by the server.
+// by the server. The call pages over the server's NextPageToken until the
+// server signals it has no more results, matching the .NET client.
 func (c *GalaxyClient) DiscoverHierarchy(ctx context.Context) ([]*GalaxyObject, error) {
+	var objects []*GalaxyObject
+	pageToken := ""
+	seen := map[string]struct{}{}
+	for {
 		callCtx, cancel := c.callContext(ctx)
-	defer cancel()
-
-	reply, err := c.raw.DiscoverHierarchy(callCtx, &pb.DiscoverHierarchyRequest{})
+		reply, err := c.raw.DiscoverHierarchy(callCtx, &pb.DiscoverHierarchyRequest{
+			PageSize:  discoverHierarchyPageSize,
+			PageToken: pageToken,
+		})
+		cancel()
 		if err != nil {
 			return nil, &GatewayError{Op: "galaxy discover hierarchy", Err: err}
 		}
-	return reply.GetObjects(), nil
+		objects = append(objects, reply.GetObjects()...)
+		pageToken = reply.GetNextPageToken()
+		if pageToken == "" {
+			return objects, nil
+		}
+		if _, dup := seen[pageToken]; dup {
+			return nil, &GatewayError{
+				Op:  "galaxy discover hierarchy",
+				Err: fmt.Errorf("repeated page token %q", pageToken),
+			}
+		}
+		seen[pageToken] = struct{}{}
+	}
 }

 // WatchDeployEventsRaw starts the generated WatchDeployEvents stream for callers
@@ -187,7 +246,7 @@ func (c *GalaxyClient) WatchDeployEvents(
 				}
 				continue
 			}
-			if errors.Is(recvErr, io.EOF) {
+			if recvErr == io.EOF {
 				return
 			}
 			if status.Code(recvErr) == codes.Canceled || ctx.Err() != nil {
@@ -212,6 +271,219 @@ func (c *GalaxyClient) Close() error {
 	return c.conn.Close()
 }

-func (c *GalaxyClient) callContext(ctx context.Context) (context.Context, context.CancelFunc) {
-	return callContext(ctx, c.opts.CallTimeout)
+// LazyBrowseNode is one node in a lazy Galaxy hierarchy walk produced by
+// (*GalaxyClient).Browse. Children are not fetched until Expand is called.
+// The node is safe for concurrent use; concurrent Expand calls coalesce onto
+// a single in-flight RPC and do not block snapshot accessors.
+type LazyBrowseNode struct {
+	client          *GalaxyClient
+	object          *pb.GalaxyObject
+	hasChildrenHint bool
+	options         BrowseChildrenOptions
+
+	// expandLock gates inspection and mutation of expand-coordination state
+	// (expanding, expandDone, expandErr). It is held only briefly; the BrowseChildren
+	// RPC itself runs outside this lock so concurrent readers and waiters are not blocked.
+	expandLock sync.Mutex
+	expanding  bool
+	expandDone chan struct{}
+	expandErr  error
+
+	// mu protects the children snapshot and isExpanded flag for concurrent
+	// Children() / IsExpanded() readers.
+	mu         sync.RWMutex
+	children   []*LazyBrowseNode
+	isExpanded bool
+}
+
+// Object returns the underlying GalaxyObject describing this node.
+func (n *LazyBrowseNode) Object() *pb.GalaxyObject { return n.object }
+
+// HasChildrenHint reports the server-supplied hint on whether this node has
+// matching descendants under the current filter set.
+func (n *LazyBrowseNode) HasChildrenHint() bool { return n.hasChildrenHint }
+
+// Children returns a snapshot copy of the currently-loaded child nodes. Returns
+// an empty slice when Expand has not yet been called.
+func (n *LazyBrowseNode) Children() []*LazyBrowseNode {
+	n.mu.RLock()
+	defer n.mu.RUnlock()
+	out := make([]*LazyBrowseNode, len(n.children))
+	copy(out, n.children)
+	return out
+}
+
+// IsExpanded reports whether Expand has completed successfully on this node.
+func (n *LazyBrowseNode) IsExpanded() bool {
+	n.mu.RLock()
+	defer n.mu.RUnlock()
+	return n.isExpanded
+}
+
+// Expand fetches this node's direct children via BrowseChildren when they have
+// not yet been loaded. Subsequent calls after a successful Expand are a no-op
+// and do not issue another RPC.
+//
+// Expand is safe to call concurrently from multiple goroutines: callers that
+// arrive while an expansion is in flight wait on the active RPC and share its
+// result instead of issuing a second RPC. The RPC itself runs without holding
+// the snapshot mutex, so concurrent Children() and IsExpanded() callers are
+// not blocked for the duration of the network round trip.
+//
+// Failure semantics: a failed expansion surfaces the same error to every
+// in-flight waiter, but the node is left in its pre-call state (isExpanded =
+// false, no in-flight expansion). The next Expand call therefore retries with
+// a fresh RPC; failures are not sticky.
+func (n *LazyBrowseNode) Expand(ctx context.Context) error {
+	// Fast path: already expanded.
+	n.mu.RLock()
+	if n.isExpanded {
+		n.mu.RUnlock()
+		return nil
+	}
+	n.mu.RUnlock()
+
+	// Either start a new expansion or wait on an existing one.
+	n.expandLock.Lock()
+	n.mu.RLock()
+	alreadyExpanded := n.isExpanded
+	n.mu.RUnlock()
+	if alreadyExpanded {
+		n.expandLock.Unlock()
+		return nil
+	}
+	if n.expanding {
+		done := n.expandDone
+		n.expandLock.Unlock()
+		select {
+		case <-done:
+			n.expandLock.Lock()
+			err := n.expandErr
+			n.expandLock.Unlock()
+			return err
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+	n.expanding = true
+	n.expandDone = make(chan struct{})
+	done := n.expandDone
+	n.expandLock.Unlock()
+
+	// Issue the RPC outside any lock so concurrent readers/waiters are not blocked.
+	parentID := n.object.GetGobjectId()
+	children, err := n.client.browseChildrenInner(ctx, &parentID, n.options)
+
+	if err == nil {
+		n.mu.Lock()
+		n.children = children
+		n.isExpanded = true
+		n.mu.Unlock()
+	}
+
+	// Publish result to waiters and clear the in-flight marker so a failed
+	// expansion can be retried by the next Expand call.
+	n.expandLock.Lock()
+	n.expandErr = err
+	n.expanding = false
+	close(done)
+	n.expandLock.Unlock()
+
+	return err
+}
+
+// Browse returns the root nodes of the Galaxy hierarchy. The returned nodes
+// have only their server-supplied hints populated; call Expand on each node to
+// fetch its direct children. When opts is nil the server defaults apply.
+func (c *GalaxyClient) Browse(ctx context.Context, opts *BrowseChildrenOptions) ([]*LazyBrowseNode, error) {
+	effective := BrowseChildrenOptions{}
+	if opts != nil {
+		effective = *opts
+	}
+	return c.browseChildrenInner(ctx, nil, effective)
+}
+
+// BrowseChildrenRaw issues a single BrowseChildren RPC and returns the raw
+// reply for callers that need direct page-token control. Transport-level
+// failures are wrapped in *GatewayError to match the rest of the client.
+func (c *GalaxyClient) BrowseChildrenRaw(ctx context.Context, req *pb.BrowseChildrenRequest) (*pb.BrowseChildrenReply, error) {
+	callCtx, cancel := c.callContext(ctx)
+	defer cancel()
+	reply, err := c.raw.BrowseChildren(callCtx, req)
+	if err != nil {
+		return nil, &GatewayError{Op: "galaxy browse children", Err: err}
+	}
+	return reply, nil
+}
+
+func (c *GalaxyClient) browseChildrenInner(
+	ctx context.Context,
+	parentGobjectID *int32,
+	opts BrowseChildrenOptions,
+) ([]*LazyBrowseNode, error) {
+	var nodes []*LazyBrowseNode
+	pageToken := ""
+	seen := map[string]struct{}{}
+	for {
+		req := &pb.BrowseChildrenRequest{
+			PageSize:              browseChildrenPageSize,
+			PageToken:             pageToken,
+			CategoryIds:           opts.CategoryIds,
+			TemplateChainContains: opts.TemplateChainContains,
+			TagNameGlob:           opts.TagNameGlob,
+			AlarmBearingOnly:      opts.AlarmBearingOnly,
+			HistorizedOnly:        opts.HistorizedOnly,
+		}
+		if parentGobjectID != nil {
+			req.Parent = &pb.BrowseChildrenRequest_ParentGobjectId{ParentGobjectId: *parentGobjectID}
+		}
+		if opts.IncludeAttributes != nil {
+			req.IncludeAttributes = opts.IncludeAttributes
+		}
+
+		reply, err := c.BrowseChildrenRaw(ctx, req)
+		if err != nil {
+			return nil, err
+		}
+
+		for i, child := range reply.GetChildren() {
+			hasChildren := reply.GetChildHasChildren()
+			hint := i < len(hasChildren) && hasChildren[i]
+			nodes = append(nodes, &LazyBrowseNode{
+				client:          c,
+				object:          child,
+				hasChildrenHint: hint,
+				options:         opts,
+			})
+		}
+
+		pageToken = reply.GetNextPageToken()
+		if pageToken == "" {
+			return nodes, nil
+		}
+		if _, dup := seen[pageToken]; dup {
+			return nil, &GatewayError{
+				Op:  "galaxy browse children",
+				Err: fmt.Errorf("repeated page token %q", pageToken),
+			}
+		}
+		seen[pageToken] = struct{}{}
+	}
+}
+
+func (c *GalaxyClient) callContext(ctx context.Context) (context.Context, context.CancelFunc) {
+	timeout := c.opts.CallTimeout
+	if timeout == 0 {
+		timeout = defaultCallTimeout
+	}
+	if timeout < 0 {
+		return ctx, func() {}
+	}
+	if deadline, ok := ctx.Deadline(); ok {
+		timeoutDeadline := time.Now().Add(timeout)
+		if deadline.Before(timeoutDeadline) {
+			return ctx, func() {}
+		}
+	}
+	return context.WithTimeout(ctx, timeout)
 }
@@ -4,11 +4,14 @@ import (
 	"context"
 	"errors"
 	"net"
+	"sync"
 	"testing"
 	"time"

 	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
 	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/test/bufconn"
 	"google.golang.org/protobuf/types/known/timestamppb"
 )
@@ -144,6 +147,47 @@ func TestGalaxyDiscoverHierarchyReturnsObjects(t *testing.T) {
 	}
 }

+func TestGalaxyDiscoverHierarchyPaginatesAcrossMultiplePages(t *testing.T) {
+	page1 := &pb.DiscoverHierarchyReply{
+		Objects: []*pb.GalaxyObject{
+			{GobjectId: 1, TagName: "A"},
+			{GobjectId: 2, TagName: "B"},
+		},
+		NextPageToken:    "page-2",
+		TotalObjectCount: 3,
+	}
+	page2 := &pb.DiscoverHierarchyReply{
+		Objects: []*pb.GalaxyObject{
+			{GobjectId: 3, TagName: "C"},
+		},
+		TotalObjectCount: 3,
+	}
+	fake := &fakeGalaxyServer{
+		discoverHierarchyReplies: []*pb.DiscoverHierarchyReply{page1, page2},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	objs, err := client.DiscoverHierarchy(context.Background())
+	if err != nil {
+		t.Fatalf("DiscoverHierarchy: %v", err)
+	}
+	if got, want := len(objs), 3; got != want {
+		t.Fatalf("len(objs) = %d, want %d", got, want)
+	}
+	if len(fake.discoverHierarchyCalls) != 2 {
+		t.Fatalf("expected 2 RPC calls, got %d", len(fake.discoverHierarchyCalls))
+	}
+	if fake.discoverHierarchyCalls[0].GetPageSize() != discoverHierarchyPageSize {
+		t.Fatalf("first call PageSize = %d, want %d",
+			fake.discoverHierarchyCalls[0].GetPageSize(), discoverHierarchyPageSize)
+	}
+	if fake.discoverHierarchyCalls[1].GetPageToken() != "page-2" {
+		t.Fatalf("second call page token = %q, want %q",
+			fake.discoverHierarchyCalls[1].GetPageToken(), "page-2")
+	}
+}
+
 func TestGalaxyDialReturnsGatewayErrorOnRpcFailure(t *testing.T) {
 	fake := &fakeGalaxyServer{failTest: true}
 	client, cleanup := newGalaxyBufconnClient(t, fake)
@@ -348,10 +392,8 @@ func newGalaxyBufconnClient(t *testing.T, fake *fakeGalaxyServer) (*GalaxyClient
 	dialer := func(ctx context.Context, _ string) (net.Conn, error) {
 		return listener.DialContext(ctx)
 	}
-	// grpc.NewClient defaults to the dns scheme; use passthrough so the
-	// bufconn fake target reaches the context dialer unresolved.
 	client, err := DialGalaxy(context.Background(), Options{
-		Endpoint:  "passthrough:///bufnet",
+		Endpoint:  "bufnet",
 		APIKey:    "test-api-key",
 		Plaintext: true,
 		DialOptions: []grpc.DialOption{
@@ -377,9 +419,15 @@ type fakeGalaxyServer struct {
 	failTest                 bool
 	deployReply              *pb.GetLastDeployTimeReply
 	discoverReply            *pb.DiscoverHierarchyReply
+	discoverHierarchyCalls   []*pb.DiscoverHierarchyRequest
+	discoverHierarchyReplies []*pb.DiscoverHierarchyReply
 	watchEvents              []*pb.DeployEvent
 	watchRequest             *pb.WatchDeployEventsRequest
+	watchSendInterval        time.Duration
 	watchHoldOpen            bool
+	browseChildrenCalls      []*pb.BrowseChildrenRequest
+	browseChildrenReplies    []*pb.BrowseChildrenReply
+	browseChildrenError      error
 }

 func (s *fakeGalaxyServer) TestConnection(ctx context.Context, req *pb.TestConnectionRequest) (*pb.TestConnectionReply, error) {
@@ -401,6 +449,12 @@ func (s *fakeGalaxyServer) GetLastDeployTime(ctx context.Context, req *pb.GetLas
 }

 func (s *fakeGalaxyServer) DiscoverHierarchy(ctx context.Context, req *pb.DiscoverHierarchyRequest) (*pb.DiscoverHierarchyReply, error) {
+	s.discoverHierarchyCalls = append(s.discoverHierarchyCalls, req)
+	if len(s.discoverHierarchyReplies) > 0 {
+		reply := s.discoverHierarchyReplies[0]
+		s.discoverHierarchyReplies = s.discoverHierarchyReplies[1:]
+		return reply, nil
+	}
 	if s.discoverReply != nil {
 		return s.discoverReply, nil
 	}
@@ -413,9 +467,398 @@ func (s *fakeGalaxyServer) WatchDeployEvents(req *pb.WatchDeployEventsRequest, s
 		if err := stream.Send(event); err != nil {
 			return err
 		}
+		if s.watchSendInterval > 0 {
+			select {
+			case <-time.After(s.watchSendInterval):
+			case <-stream.Context().Done():
+				return stream.Context().Err()
+			}
+		}
 	}
 	if s.watchHoldOpen {
 		<-stream.Context().Done()
 	}
 	return nil
 }
+
+func (s *fakeGalaxyServer) BrowseChildren(ctx context.Context, req *pb.BrowseChildrenRequest) (*pb.BrowseChildrenReply, error) {
+	s.browseChildrenCalls = append(s.browseChildrenCalls, req)
+	if s.browseChildrenError != nil {
+		err := s.browseChildrenError
+		s.browseChildrenError = nil
+		return nil, err
+	}
+	if len(s.browseChildrenReplies) == 0 {
+		return &pb.BrowseChildrenReply{}, nil
+	}
+	reply := s.browseChildrenReplies[0]
+	s.browseChildrenReplies = s.browseChildrenReplies[1:]
+	return reply, nil
+}
+
+func obj(id int32, tag string, isArea bool) *pb.GalaxyObject {
+	return &pb.GalaxyObject{
+		GobjectId:  id,
+		TagName:    tag,
+		BrowseName: tag,
+		IsArea:     isArea,
+	}
+}
+
+func buildBrowseReply(children []*pb.GalaxyObject, hasChildren []bool, seq uint64) *pb.BrowseChildrenReply {
+	return &pb.BrowseChildrenReply{
+		TotalChildCount:  int32(len(children)),
+		CacheSequence:    seq,
+		Children:         children,
+		ChildHasChildren: hasChildren,
+	}
+}
+
+func TestGalaxyBrowseNoParentReturnsRoots(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(1, "Plant", true), obj(99, "Other", false)},
+				[]bool{true, false},
+				7,
+			),
+		},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	roots, err := client.Browse(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	if got, want := len(roots), 2; got != want {
+		t.Fatalf("len(roots) = %d, want %d", got, want)
+	}
+	if roots[0].Object().GetTagName() != "Plant" {
+		t.Fatalf("roots[0].TagName = %q", roots[0].Object().GetTagName())
+	}
+	if !roots[0].HasChildrenHint() {
+		t.Fatal("roots[0].HasChildrenHint = false, want true")
+	}
+	if roots[0].IsExpanded() {
+		t.Fatal("roots[0].IsExpanded = true, want false")
+	}
+	if roots[1].HasChildrenHint() {
+		t.Fatal("roots[1].HasChildrenHint = true, want false")
+	}
+	if len(fake.browseChildrenCalls) != 1 {
+		t.Fatalf("BrowseChildren calls = %d, want 1", len(fake.browseChildrenCalls))
+	}
+	if fake.browseChildrenCalls[0].GetParent() != nil {
+		t.Fatalf("root browse should not set Parent oneof, got %T", fake.browseChildrenCalls[0].GetParent())
+	}
+}
+
+func TestGalaxyBrowseExpandPopulatesChildrenAndMarksExpanded(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(1, "Plant", true)},
+				[]bool{true},
+				1,
+			),
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(10, "Area1", true), obj(11, "Tank1", false)},
+				[]bool{true, false},
+				1,
+			),
+		},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	roots, err := client.Browse(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	if len(roots) != 1 {
+		t.Fatalf("len(roots) = %d, want 1", len(roots))
+	}
+	plant := roots[0]
+	if plant.IsExpanded() {
+		t.Fatal("plant.IsExpanded = true before Expand, want false")
+	}
+	if err := plant.Expand(context.Background()); err != nil {
+		t.Fatalf("Expand: %v", err)
+	}
+	if !plant.IsExpanded() {
+		t.Fatal("plant.IsExpanded = false after Expand, want true")
+	}
+	children := plant.Children()
+	if len(children) != 2 {
+		t.Fatalf("len(children) = %d, want 2", len(children))
+	}
+	if children[0].Object().GetTagName() != "Area1" {
+		t.Fatalf("children[0].TagName = %q, want Area1", children[0].Object().GetTagName())
+	}
+	if !children[0].HasChildrenHint() {
+		t.Fatal("children[0].HasChildrenHint = false, want true")
+	}
+	if children[1].HasChildrenHint() {
+		t.Fatal("children[1].HasChildrenHint = true, want false")
+	}
+	if len(fake.browseChildrenCalls) != 2 {
+		t.Fatalf("BrowseChildren calls = %d, want 2", len(fake.browseChildrenCalls))
+	}
+	parent := fake.browseChildrenCalls[1].GetParent()
+	parentGobj, ok := parent.(*pb.BrowseChildrenRequest_ParentGobjectId)
+	if !ok {
+		t.Fatalf("Parent oneof = %T, want *BrowseChildrenRequest_ParentGobjectId", parent)
+	}
+	if parentGobj.ParentGobjectId != 1 {
+		t.Fatalf("ParentGobjectId = %d, want 1", parentGobj.ParentGobjectId)
+	}
+}
+
+func TestGalaxyBrowseExpandIdempotentNoSecondRpc(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(1, "Plant", true)},
+				[]bool{true},
+				1,
+			),
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(10, "Area1", true)},
+				[]bool{false},
+				1,
+			),
+		},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	roots, err := client.Browse(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	plant := roots[0]
+	if err := plant.Expand(context.Background()); err != nil {
+		t.Fatalf("Expand #1: %v", err)
+	}
+	callsAfterFirst := len(fake.browseChildrenCalls)
+	if callsAfterFirst != 2 {
+		t.Fatalf("BrowseChildren calls after first Expand = %d, want 2", callsAfterFirst)
+	}
+	if err := plant.Expand(context.Background()); err != nil {
+		t.Fatalf("Expand #2: %v", err)
+	}
+	if got := len(fake.browseChildrenCalls); got != callsAfterFirst {
+		t.Fatalf("BrowseChildren calls after second Expand = %d, want %d (no extra RPC)", got, callsAfterFirst)
+	}
+}
+
+func TestGalaxyBrowseExpandUnknownParentReturnsNotFoundError(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			buildBrowseReply(
+				[]*pb.GalaxyObject{obj(1, "Plant", true)},
+				[]bool{true},
+				1,
+			),
+		},
+		browseChildrenError: status.Error(codes.NotFound, "parent not found"),
+	}
+	// The first Browse() consumes the first reply; the next call (Expand) will
+	// then hit browseChildrenError. We need the error to fire only on the second
+	// call, so seed the reply first and let the call sequence consume them in
+	// order. Because BrowseChildren in the fake consumes browseChildrenError
+	// before falling through to replies, swap the strategy: keep the root reply
+	// but have BrowseChildren return the error on the second call. We do this by
+	// emptying the reply list after the first Browse.
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	// First call returns the error (because browseChildrenError takes precedence).
+	// To avoid that, clear it for the root call by performing a manual setup: we
+	// pre-stage replies first, then set the error after the first call. Easiest:
+	// pre-Browse() with error=nil, then set error before Expand.
+	fake.browseChildrenError = nil
+	roots, err := client.Browse(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	if len(roots) != 1 {
+		t.Fatalf("len(roots) = %d, want 1", len(roots))
+	}
+	fake.browseChildrenError = status.Error(codes.NotFound, "parent not found")
+
+	err = roots[0].Expand(context.Background())
+	if err == nil {
+		t.Fatal("Expand: error = nil, want NotFound")
+	}
+	if status.Code(err) != codes.NotFound {
+		t.Fatalf("status.Code = %s, want NotFound", status.Code(err))
+	}
+	if roots[0].IsExpanded() {
+		t.Fatal("roots[0].IsExpanded = true after failed Expand, want false")
+	}
+}
+
+func TestGalaxyBrowseExpandMultiPageGathersAllPages(t *testing.T) {
+	firstPage := buildBrowseReply(
+		[]*pb.GalaxyObject{obj(1, "Plant", true)},
+		[]bool{true},
+		7,
+	)
+
+	pageA := buildBrowseReply(
+		[]*pb.GalaxyObject{obj(10, "Child1", false), obj(11, "Child2", false)},
+		[]bool{false, false},
+		7,
+	)
+	pageA.NextPageToken = "7:abc:2"
+	pageB := buildBrowseReply(
+		[]*pb.GalaxyObject{obj(12, "Child3", false)},
+		[]bool{false},
+		7,
+	)
+
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{firstPage, pageA, pageB},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	roots, err := client.Browse(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	if err := roots[0].Expand(context.Background()); err != nil {
+		t.Fatalf("Expand: %v", err)
+	}
+	children := roots[0].Children()
+	if len(children) != 3 {
+		t.Fatalf("len(children) = %d, want 3", len(children))
+	}
+	if len(fake.browseChildrenCalls) != 3 {
+		t.Fatalf("BrowseChildren calls = %d, want 3", len(fake.browseChildrenCalls))
+	}
+	if got := fake.browseChildrenCalls[2].GetPageToken(); got != "7:abc:2" {
+		t.Fatalf("third call PageToken = %q, want %q", got, "7:abc:2")
+	}
+}
+
+func TestGalaxyBrowseWithFilterForwardsToRequest(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			buildBrowseReply(nil, nil, 1),
+		},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	include := true
+	opts := &BrowseChildrenOptions{
+		CategoryIds:           []int32{7, 9},
+		TemplateChainContains: []string{"$AppObject"},
+		TagNameGlob:           "Tank*",
+		IncludeAttributes:     &include,
+		AlarmBearingOnly:      true,
+		HistorizedOnly:        true,
+	}
+	if _, err := client.Browse(context.Background(), opts); err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+	if len(fake.browseChildrenCalls) != 1 {
+		t.Fatalf("BrowseChildren calls = %d, want 1", len(fake.browseChildrenCalls))
+	}
+	got := fake.browseChildrenCalls[0]
+	if want := []int32{7, 9}; len(got.GetCategoryIds()) != 2 || got.GetCategoryIds()[0] != want[0] || got.GetCategoryIds()[1] != want[1] {
+		t.Fatalf("CategoryIds = %v, want %v", got.GetCategoryIds(), want)
+	}
+	if want := []string{"$AppObject"}; len(got.GetTemplateChainContains()) != 1 || got.GetTemplateChainContains()[0] != want[0] {
+		t.Fatalf("TemplateChainContains = %v, want %v", got.GetTemplateChainContains(), want)
+	}
+	if got.GetTagNameGlob() != "Tank*" {
+		t.Fatalf("TagNameGlob = %q, want %q", got.GetTagNameGlob(), "Tank*")
+	}
+	if !got.GetIncludeAttributes() {
+		t.Fatal("IncludeAttributes = false, want true")
+	}
+	if !got.GetAlarmBearingOnly() {
+		t.Fatal("AlarmBearingOnly = false, want true")
+	}
+	if !got.GetHistorizedOnly() {
+		t.Fatal("HistorizedOnly = false, want true")
+	}
+}
+
+func TestGalaxyBrowseExpandConcurrentCallersOnlyFireOneRpc(t *testing.T) {
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{
+			// roots
+			buildBrowseReply([]*pb.GalaxyObject{obj(1, "Plant", true)}, []bool{true}, 7),
+			// one expand: one child
+			buildBrowseReply([]*pb.GalaxyObject{obj(2, "Mixer", false)}, []bool{false}, 7),
+		},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	ctx := context.Background()
+	roots, err := client.Browse(ctx, nil)
+	if err != nil {
+		t.Fatalf("Browse: %v", err)
+	}
+
+	var wg sync.WaitGroup
+	errs := make(chan error, 10)
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			errs <- roots[0].Expand(ctx)
+		}()
+	}
+	wg.Wait()
+	close(errs)
+	for err := range errs {
+		if err != nil {
+			t.Fatalf("concurrent Expand: %v", err)
+		}
+	}
+
+	if !roots[0].IsExpanded() {
+		t.Fatal("IsExpanded() = false after 10 concurrent expands")
+	}
+	if got, want := len(roots[0].Children()), 1; got != want {
+		t.Fatalf("len(children) = %d, want %d", got, want)
+	}
+	// 1 roots fetch + exactly 1 expand fetch.
+	if got, want := len(fake.browseChildrenCalls), 2; got != want {
+		t.Fatalf("RPC count = %d, want %d", got, want)
+	}
+}
+
+func TestGalaxyBrowseChildrenRejectsRepeatedPageToken(t *testing.T) {
+	// Build a reply that carries a non-empty NextPageToken so browseChildrenInner
+	// will request a second page. Queue the same reply twice so the second response
+	// returns the same page token, triggering the duplicate-token guard.
+	page := buildBrowseReply(
+		[]*pb.GalaxyObject{obj(1, "Plant", true)},
+		[]bool{true},
+		1,
+	)
+	page.NextPageToken = "1:abc:1"
+
+	fake := &fakeGalaxyServer{
+		browseChildrenReplies: []*pb.BrowseChildrenReply{page, page},
+	}
+	client, cleanup := newGalaxyBufconnClient(t, fake)
+	defer cleanup()
+
+	_, err := client.Browse(context.Background(), nil)
+	if err == nil {
+		t.Fatal("Browse: error = nil, want repeated-page-token error")
+	}
+	var gwErr *GatewayError
+	if !errors.As(err, &gwErr) {
+		t.Fatalf("error type = %T, want *GatewayError; err = %v", err, err)
+	}
+}
@@ -34,6 +34,32 @@ type Options struct {
 	TransportCredentials credentials.TransportCredentials
 	// DialOptions are appended to the gRPC dial options after the defaults.
 	DialOptions []grpc.DialOption
+	// RequireCertificateValidation forces TLS certificate verification even when
+	// no CACertFile is pinned. Default false: the gateway's self-signed cert is
+	// accepted without verification (internal-tool posture).
+	RequireCertificateValidation bool
+}
+
+// BrowseChildrenOptions configures lazy Galaxy hierarchy walks performed by
+// (*GalaxyClient).Browse and (*LazyBrowseNode).Expand. All fields are optional;
+// the zero value matches the dashboard default (no filters, all attributes per
+// the server default).
+type BrowseChildrenOptions struct {
+	// CategoryIds restricts results to the listed Galaxy category ids when set.
+	CategoryIds []int32
+	// TemplateChainContains restricts results to objects whose template chain
+	// contains any of the listed template tag names.
+	TemplateChainContains []string
+	// TagNameGlob restricts results to objects whose tag name matches the glob
+	// pattern when non-empty.
+	TagNameGlob string
+	// IncludeAttributes overrides the server default for attribute inclusion when
+	// non-nil. The pointer form mirrors the proto's optional field.
+	IncludeAttributes *bool
+	// AlarmBearingOnly limits results to alarm-bearing objects when true.
+	AlarmBearingOnly bool
+	// HistorizedOnly limits results to historized objects when true.
+	HistorizedOnly bool
 }

 // RedactedAPIKey returns a display-safe representation of the configured API
@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"io"
 	"sync"
-	"sync/atomic"
 	"time"

 	pb "gitea.dohertylan.com/dohertj2/mxaccessgw/clients/go/internal/generated"
@@ -393,6 +392,9 @@ func (s *Session) UnsubscribeBulk(ctx context.Context, serverHandle int32, itemH
 // Per-entry failures appear as BulkWriteResult entries with WasSuccessful=false; the call
 // never returns an error for per-entry MXAccess failures (it returns an error only for
 // protocol-level failures or transport errors).
+//
+// A non-nil but empty entries slice is treated as a no-op and returns an empty result
+// without a wire round-trip; pass nil to surface a clear "entries are required" error.
 func (s *Session) WriteBulk(ctx context.Context, serverHandle int32, entries []*WriteBulkEntry) ([]*BulkWriteResult, error) {
 	if entries == nil {
 		return nil, errors.New("mxgateway: write bulk entries are required")
@@ -400,6 +402,9 @@ func (s *Session) WriteBulk(ctx context.Context, serverHandle int32, entries []*
 	if err := ensureBulkSize("write bulk entries", len(entries)); err != nil {
 		return nil, err
 	}
+	if len(entries) == 0 {
+		return []*BulkWriteResult{}, nil
+	}
 	reply, err := s.invokeCommand(ctx, &pb.MxCommand{
 		Kind: pb.MxCommandKind_MX_COMMAND_KIND_WRITE_BULK,
 		Payload: &pb.MxCommand_WriteBulk{
@@ -416,6 +421,9 @@ func (s *Session) WriteBulk(ctx context.Context, serverHandle int32, entries []*
 }

 // Write2Bulk invokes MXAccess Write2 (timestamped) for each entry inside one gateway command.
+//
+// A non-nil but empty entries slice is treated as a no-op and returns an empty result
+// without a wire round-trip; pass nil to surface a clear "entries are required" error.
 func (s *Session) Write2Bulk(ctx context.Context, serverHandle int32, entries []*Write2BulkEntry) ([]*BulkWriteResult, error) {
 	if entries == nil {
 		return nil, errors.New("mxgateway: write2 bulk entries are required")
@@ -423,6 +431,9 @@ func (s *Session) Write2Bulk(ctx context.Context, serverHandle int32, entries []
 	if err := ensureBulkSize("write2 bulk entries", len(entries)); err != nil {
 		return nil, err
 	}
+	if len(entries) == 0 {
+		return []*BulkWriteResult{}, nil
+	}
 	reply, err := s.invokeCommand(ctx, &pb.MxCommand{
 		Kind: pb.MxCommandKind_MX_COMMAND_KIND_WRITE2_BULK,
 		Payload: &pb.MxCommand_Write2Bulk{
@@ -440,6 +451,9 @@ func (s *Session) Write2Bulk(ctx context.Context, serverHandle int32, entries []

 // WriteSecuredBulk invokes MXAccess WriteSecured for each entry. Credential-sensitive
 // values must not be logged by callers; mirrors the single-item WriteSecured contract.
+//
+// A non-nil but empty entries slice is treated as a no-op and returns an empty result
+// without a wire round-trip; pass nil to surface a clear "entries are required" error.
 func (s *Session) WriteSecuredBulk(ctx context.Context, serverHandle int32, entries []*WriteSecuredBulkEntry) ([]*BulkWriteResult, error) {
 	if entries == nil {
 		return nil, errors.New("mxgateway: write-secured bulk entries are required")
@@ -447,6 +461,9 @@ func (s *Session) WriteSecuredBulk(ctx context.Context, serverHandle int32, entr
 	if err := ensureBulkSize("write-secured bulk entries", len(entries)); err != nil {
 		return nil, err
 	}
+	if len(entries) == 0 {
+		return []*BulkWriteResult{}, nil
+	}
 	reply, err := s.invokeCommand(ctx, &pb.MxCommand{
 		Kind: pb.MxCommandKind_MX_COMMAND_KIND_WRITE_SECURED_BULK,
 		Payload: &pb.MxCommand_WriteSecuredBulk{
@@ -463,6 +480,9 @@ func (s *Session) WriteSecuredBulk(ctx context.Context, serverHandle int32, entr
 }

 // WriteSecured2Bulk invokes MXAccess WriteSecured2 (timestamped) for each entry.
+//
+// A non-nil but empty entries slice is treated as a no-op and returns an empty result
+// without a wire round-trip; pass nil to surface a clear "entries are required" error.
 func (s *Session) WriteSecured2Bulk(ctx context.Context, serverHandle int32, entries []*WriteSecured2BulkEntry) ([]*BulkWriteResult, error) {
 	if entries == nil {
 		return nil, errors.New("mxgateway: write-secured2 bulk entries are required")
@@ -470,6 +490,9 @@ func (s *Session) WriteSecured2Bulk(ctx context.Context, serverHandle int32, ent
 	if err := ensureBulkSize("write-secured2 bulk entries", len(entries)); err != nil {
 		return nil, err
 	}
+	if len(entries) == 0 {
+		return []*BulkWriteResult{}, nil
+	}
 	reply, err := s.invokeCommand(ctx, &pb.MxCommand{
 		Kind: pb.MxCommandKind_MX_COMMAND_KIND_WRITE_SECURED2_BULK,
 		Payload: &pb.MxCommand_WriteSecured2Bulk{
@@ -493,6 +516,10 @@ func (s *Session) WriteSecured2Bulk(ctx context.Context, serverHandle int32, ent
 // otherwise. timeout bounds the wait per tag in the snapshot case; pass zero to use the
 // worker default. Per-tag failures (timeout, invalid tag) appear as BulkReadResult entries
 // with WasSuccessful=false; the call never returns an error for per-tag MXAccess failures.
+//
+// A non-nil but empty tagAddresses slice is treated as a no-op and returns an empty
+// result without a wire round-trip; pass nil to surface a clear "tag addresses are
+// required" error.
 func (s *Session) ReadBulk(ctx context.Context, serverHandle int32, tagAddresses []string, timeout time.Duration) ([]*BulkReadResult, error) {
 	if tagAddresses == nil {
 		return nil, errors.New("mxgateway: tag addresses are required")
@@ -500,6 +527,9 @@ func (s *Session) ReadBulk(ctx context.Context, serverHandle int32, tagAddresses
 	if err := ensureBulkSize("tag addresses", len(tagAddresses)); err != nil {
 		return nil, err
 	}
+	if len(tagAddresses) == 0 {
+		return []*BulkReadResult{}, nil
+	}
 	var timeoutMs uint32
 	if timeout > 0 {
 		ms := timeout.Milliseconds()
@@ -599,7 +629,7 @@ func (s *Session) subscribeEventsAfter(ctx context.Context, afterWorkerSequence
 				}
 				continue
 			}
-			if errors.Is(err, io.EOF) || status.Code(err) == codes.Canceled || streamCtx.Err() != nil {
+			if err == io.EOF || status.Code(err) == codes.Canceled || streamCtx.Err() != nil {
 				return
 			}
 			sendEventResult(
@@ -628,7 +658,7 @@ func ensureBulkSize(name string, length int) error {

 func sendEventResult(
 	ctx context.Context,
-	results chan EventResult,
+	results chan<- EventResult,
 	result EventResult,
 	cancelWhenBufferFull bool,
 	cancel context.CancelFunc,
@@ -640,12 +670,7 @@ func sendEventResult(
 		case <-ctx.Done():
 			return false
 		default:
-			// The bounded compatibility buffer is full. Cancel the stream and
-			// deliver an explicit terminal overflow error so a slow consumer
-			// can tell dropped events apart from a normal end-of-stream,
-			// rather than seeing the channel close silently.
 			cancel()
-			deliverTerminalResult(results, EventResult{Err: ErrEventBufferOverflow})
 			return false
 		}
 	}
@@ -658,25 +683,6 @@ func sendEventResult(
 	}
 }

-// deliverTerminalResult places result on a full buffered channel by evicting
-// one of the oldest buffered events to make room. The caller closes results
-// afterwards, so the terminal result becomes the consumer's last item.
-func deliverTerminalResult(results chan EventResult, result EventResult) {
-	for {
-		select {
-		case results <- result:
-			return
-		default:
-		}
-		select {
-		case <-results:
-		default:
-			// Another receiver drained the channel between the send and
-			// receive attempts; retry the send.
-		}
-	}
-}
-
 func (s *Session) invokeCommand(ctx context.Context, command *MxCommand) (*MxCommandReply, error) {
 	return s.client.Invoke(ctx, &pb.MxCommandRequest{
 		SessionId:           s.ID(),
@@ -685,25 +691,10 @@ func (s *Session) invokeCommand(ctx context.Context, command *MxCommand) (*MxCom
 	})
 }

-// correlationIDCounter backs the deterministic fallback id used when
-// crypto/rand is unavailable, so every command still carries a unique,
-// traceable correlation id.
-var correlationIDCounter atomic.Uint64
-
-// randRead is the entropy source for newCorrelationID. It is a package
-// variable solely so tests can simulate a crypto/rand failure.
-var randRead = rand.Read
-
-// newCorrelationID returns a unique correlation id for an MxCommandRequest.
-// It prefers 16 bytes of crypto/rand entropy; if rand.Read fails (rare) it
-// falls back to a "fallback-" prefixed id built from the current time and a
-// process-wide monotonic counter rather than returning an empty string, which
-// would leave the command untraceable in gateway logs.
 func newCorrelationID() string {
 	var buffer [16]byte
-	if _, err := randRead(buffer[:]); err != nil {
-		return fmt.Sprintf("fallback-%x-%x",
-			time.Now().UnixNano(), correlationIDCounter.Add(1))
+	if _, err := rand.Read(buffer[:]); err != nil {
+		return ""
 	}
 	return hex.EncodeToString(buffer[:])
 }
@@ -70,32 +70,32 @@ type (
 	WriteCommand = pb.WriteCommand
 	// Write2Command is the payload of an MXAccess Write2 command.
 	Write2Command = pb.Write2Command
-	// WriteBulkCommand carries one bulk-Write request.
+	// WriteBulkCommand is the payload of a bulk Write command.
 	WriteBulkCommand = pb.WriteBulkCommand
-	// WriteBulkEntry is one (item_handle, value, user_id) tuple in a WriteBulk request.
+	// WriteBulkEntry is one entry inside a WriteBulkCommand.
 	WriteBulkEntry = pb.WriteBulkEntry
-	// Write2BulkCommand carries one bulk-Write2 (timestamped) request.
+	// Write2BulkCommand is the payload of a bulk Write2 (timestamped) command.
 	Write2BulkCommand = pb.Write2BulkCommand
-	// Write2BulkEntry is one (item_handle, value, timestamp_value, user_id) tuple in a Write2Bulk request.
+	// Write2BulkEntry is one entry inside a Write2BulkCommand.
 	Write2BulkEntry = pb.Write2BulkEntry
-	// WriteSecuredBulkCommand carries one bulk-WriteSecured request. Values are credential-sensitive.
+	// WriteSecuredBulkCommand is the payload of a bulk WriteSecured command.
 	WriteSecuredBulkCommand = pb.WriteSecuredBulkCommand
-	// WriteSecuredBulkEntry is one entry in a WriteSecuredBulk request.
+	// WriteSecuredBulkEntry is one entry inside a WriteSecuredBulkCommand.
 	WriteSecuredBulkEntry = pb.WriteSecuredBulkEntry
-	// WriteSecured2BulkCommand carries one bulk-WriteSecured2 (timestamped) request.
+	// WriteSecured2BulkCommand is the payload of a bulk WriteSecured2 (timestamped) command.
 	WriteSecured2BulkCommand = pb.WriteSecured2BulkCommand
-	// WriteSecured2BulkEntry is one entry in a WriteSecured2Bulk request.
+	// WriteSecured2BulkEntry is one entry inside a WriteSecured2BulkCommand.
 	WriteSecured2BulkEntry = pb.WriteSecured2BulkEntry
-	// ReadBulkCommand carries one bulk-Read request.
+	// ReadBulkCommand is the payload of a bulk Read snapshot command.
 	ReadBulkCommand = pb.ReadBulkCommand
-	// BulkWriteResult is one per-entry result in a bulk-write reply.
-	BulkWriteResult = pb.BulkWriteResult
-	// BulkWriteReply aggregates BulkWriteResult entries for a bulk-write command.
+	// BulkWriteReply aggregates BulkWriteResult entries for a bulk write command.
 	BulkWriteReply = pb.BulkWriteReply
-	// BulkReadResult is one per-tag result in a bulk-read reply (carries the snapshot value plus a was_cached flag).
-	BulkReadResult = pb.BulkReadResult
-	// BulkReadReply aggregates BulkReadResult entries for a ReadBulk command.
+	// BulkWriteResult is one entry in a bulk write reply list.
+	BulkWriteResult = pb.BulkWriteResult
+	// BulkReadReply aggregates BulkReadResult entries for a bulk read command.
 	BulkReadReply = pb.BulkReadReply
+	// BulkReadResult is one entry in a bulk read reply list.
+	BulkReadResult = pb.BulkReadResult
 	// RegisterReply carries the ServerHandle returned by Register.
 	RegisterReply = pb.RegisterReply
 	// AddItemReply carries the ItemHandle returned by AddItem.
@@ -110,12 +110,14 @@ type (
 	AcknowledgeAlarmRequest = pb.AcknowledgeAlarmRequest
 	// AcknowledgeAlarmReply is the gateway AcknowledgeAlarm reply message.
 	AcknowledgeAlarmReply = pb.AcknowledgeAlarmReply
+	// QueryActiveAlarmsRequest is the gateway QueryActiveAlarms request message.
+	QueryActiveAlarmsRequest = pb.QueryActiveAlarmsRequest
 	// StreamAlarmsRequest is the gateway StreamAlarms request message.
 	StreamAlarmsRequest = pb.StreamAlarmsRequest
 	// AlarmFeedMessage is one message on the StreamAlarms feed — an
 	// active-alarm snapshot row, a snapshot-complete sentinel, or a transition.
 	AlarmFeedMessage = pb.AlarmFeedMessage
-	// ActiveAlarmSnapshot is one currently-active alarm in the feed snapshot.
+	// ActiveAlarmSnapshot is one row in a ConditionRefresh stream.
 	ActiveAlarmSnapshot = pb.ActiveAlarmSnapshot
 	// OnAlarmTransitionEvent is the body carried by alarm-transition MxEvents.
 	OnAlarmTransitionEvent = pb.OnAlarmTransitionEvent
@@ -129,6 +131,10 @@ type AlarmTransitionKind = pb.AlarmTransitionKind
 // ConditionRefresh snapshot.
 type AlarmConditionState = pb.AlarmConditionState

+// QueryActiveAlarmsClient is the generated server-streaming client for the
+// QueryActiveAlarms RPC.
+type QueryActiveAlarmsClient = pb.MxAccessGateway_QueryActiveAlarmsClient
+
 // StreamAlarmsClient is the generated server-streaming client for the
 // StreamAlarms RPC.
 type StreamAlarmsClient = pb.MxAccessGateway_StreamAlarmsClient
@@ -184,16 +190,6 @@ const (
 	CommandKindWrite = pb.MxCommandKind_MX_COMMAND_KIND_WRITE
 	// CommandKindWrite2 selects the MXAccess Write2 command.
 	CommandKindWrite2 = pb.MxCommandKind_MX_COMMAND_KIND_WRITE2
-	// CommandKindWriteBulk selects the bulk Write command.
-	CommandKindWriteBulk = pb.MxCommandKind_MX_COMMAND_KIND_WRITE_BULK
-	// CommandKindWrite2Bulk selects the bulk Write2 (timestamped) command.
-	CommandKindWrite2Bulk = pb.MxCommandKind_MX_COMMAND_KIND_WRITE2_BULK
-	// CommandKindWriteSecuredBulk selects the bulk WriteSecured command.
-	CommandKindWriteSecuredBulk = pb.MxCommandKind_MX_COMMAND_KIND_WRITE_SECURED_BULK
-	// CommandKindWriteSecured2Bulk selects the bulk WriteSecured2 (timestamped) command.
-	CommandKindWriteSecured2Bulk = pb.MxCommandKind_MX_COMMAND_KIND_WRITE_SECURED2_BULK
-	// CommandKindReadBulk selects the bulk Read command (cached-or-snapshot per tag).
-	CommandKindReadBulk = pb.MxCommandKind_MX_COMMAND_KIND_READ_BULK

 	// DataTypeUnknown denotes an unrecognized MXAccess data type.
 	DataTypeUnknown = pb.MxDataType_MX_DATA_TYPE_UNKNOWN
@@ -18,13 +18,13 @@ clients/java/
  settings.gradle
  build.gradle
  src/main/generated/
-  mxgateway-client/
+  zb-mom-ww-mxgateway-client/
    build.gradle
-    src/main/java/com/dohertylan/mxgateway/client/
-    src/test/java/com/dohertylan/mxgateway/client/
-  mxgateway-cli/
+    src/main/java/com/zb/mom/ww/mxgateway/client/
+    src/test/java/com/zb/mom/ww/mxgateway/client/
+  zb-mom-ww-mxgateway-cli/
    build.gradle
-    src/main/java/com/dohertylan/mxgateway/cli/
+    src/main/java/com/zb/mom/ww/mxgateway/cli/
 ```

 Alternative Maven layout is acceptable if the repo standardizes on Maven.
@@ -112,6 +112,23 @@ Support:
 - custom CA certificate file,
 - server name override for test environments.

+### Trust posture
+
+The gateway can serve a self-signed certificate it generates itself (it has no
+PKI). To make that usable, TLS is **lenient by default**: when the channel is not
+plaintext and no `caCertificatePath` is set, the client builds
+`GrpcSslContexts.forClient().trustManager(InsecureTrustManagerFactory.INSTANCE)`
+(grpc-netty-shaded), so the gateway's self-signed certificate is accepted without
+verification.
+
+To verify the gateway instead:
+
+- set `caCertificatePath` to pin a CA (full verification against that root), or
+- set `requireCertificateValidation` to `true` to verify against the JVM trust
+  store without pinning.
+
+Pinning a CA always wins over the lenient default.
+
 ## Streaming

 Support both:
@@ -192,8 +209,8 @@ stream for bounded time, and close.

 Publish library and CLI separately:

- `mxgateway-client` jar,
- `mxgateway-cli` runnable distribution.
+- `zb-mom-ww-mxgateway-client` jar,
+- `zb-mom-ww-mxgateway-cli` runnable distribution.

 Generated protobuf code should be produced during the build from shared proto
 files and should not be hand-edited.
@@ -206,10 +223,10 @@ Run the Java scaffold checks from `clients/java`:
 gradle test
 ```

-The `mxgateway-client` project generates the gateway and worker protobuf/gRPC
-bindings into `src/main/generated`, compiles the generated contracts, and runs
-JUnit 5 tests. The `mxgateway-cli` project builds a Picocli-based `mxgw-java`
-entry point for later command implementation.
+The `zb-mom-ww-mxgateway-client` project generates the gateway and worker
+protobuf/gRPC bindings into `src/main/generated`, compiles the generated
+contracts, and runs JUnit 5 tests. The `zb-mom-ww-mxgateway-cli` project
+builds a Picocli-based `mxgw-java` entry point for later command implementation.

 ## Related Documentation

@@ -10,22 +10,23 @@ clients/java/
  settings.gradle
  build.gradle
  src/main/generated/
-  mxgateway-client/
-  mxgateway-cli/
+  zb-mom-ww-mxgateway-client/
+  zb-mom-ww-mxgateway-cli/
 ```

-`mxgateway-client` generates Java protobuf and gRPC sources from
-`../../src/MxGateway.Contracts/Protos`. The Gradle protobuf plugin writes those
+`zb-mom-ww-mxgateway-client` generates Java protobuf and gRPC sources from
+`../../src/ZB.MOM.WW.MxGateway.Contracts/Protos`. The Gradle protobuf plugin writes those
 generated sources under `src/main/generated`, which matches the client proto
 manifest in `../proto/proto-inputs.json`. Do not edit generated files by hand.

-`mxgateway-client` exposes `MxGatewayClientOptions`, `MxGatewayClient`,
+`zb-mom-ww-mxgateway-client` exposes `MxGatewayClientOptions`, `MxGatewayClient`,
 `MxGatewaySession`, value/status helpers, typed gateway exceptions, raw
 generated stubs, and generated protobuf messages for parity tests.

-`mxgateway-cli` depends on `mxgateway-client` and provides the `mxgw-java`
-application entry point. The CLI supports version, session, command, event
-streaming, write, and smoke-test commands with deterministic JSON output.
+`zb-mom-ww-mxgateway-cli` depends on `zb-mom-ww-mxgateway-client` and provides
+the `mxgw-java` application entry point. The CLI supports version, session,
+command, event streaming, write, and smoke-test commands with deterministic
+JSON output.

 ## Regenerating Protobuf Bindings

@@ -33,7 +34,7 @@ Run generation from `clients/java` after the shared `.proto` files or Java
 output path changes:

 ```powershell
-gradle :mxgateway-client:generateProto
+gradle :zb-mom-ww-mxgateway-client:generateProto
 ```

 ## Client Usage
@@ -56,66 +57,32 @@ try (MxGatewayClient client = MxGatewayClient.connect(options);
 }
 ```

+The gateway can auto-generate its own self-signed certificate (it has no PKI), so
+the client is **lenient by default**: a TLS connection (`plaintext(false)`) with
+no `caCertificatePath` accepts whatever certificate the gateway presents (via
+grpc-netty-shaded's `InsecureTrustManagerFactory`). To verify instead, set
+`caCertificatePath` to pin a CA, or set `requireCertificateValidation(true)` to
+verify against the JVM trust store without pinning. Use `serverNameOverride` /
+`--server-name-override` when the dialed host differs from the certificate SAN.
+See
+[Gateway Configuration](../../docs/GatewayConfiguration.md#automatic-self-signed-certificate).
+
 Use `rawBlockingStub`, `rawFutureStub`, `rawAsyncStub`, `openSessionRaw`,
 `closeSessionRaw`, `invoke`, and raw session helper methods when tests need the
 underlying protobuf messages. `MxGatewayCommandException` and
 `MxAccessException` preserve the raw `MxCommandReply` when the gateway returns a
 data-bearing MXAccess failure.

-`MxGatewaySession` exposes the full bulk family — `addItemBulk`,
-`adviseItemBulk`, `removeItemBulk`, `unAdviseItemBulk`, `subscribeBulk`,
-`unsubscribeBulk`, `writeBulk`, `write2Bulk`, `writeSecuredBulk`,
-`writeSecured2Bulk`, and `readBulk`. Each carries one round-trip with a
-`List<*Entry>` (or `List<String>` / `List<Integer>` for the legacy bulk
-shapes) and returns `List<SubscribeResult>` / `List<BulkWriteResult>` /
-`List<BulkReadResult>`; per-entry MXAccess failures populate
-`wasSuccessful == false` and never throw. `readBulk` takes a per-tag
-`timeoutMs` (0 = worker default) and returns cached `OnDataChange` values
-when the tag is already advised (`wasCached == true`) without touching the
-existing subscription.
-
-`openSession` verifies the gateway's reported `gateway_protocol_version` against
-the version this client was generated for and throws `MxGatewayException` on a
-mismatch, so an incompatible client fails fast with a clear message instead of
-issuing commands that fail downstream. A gateway that does not populate the
-field is accepted unchanged.
-
-`MxGatewaySession` implements `AutoCloseable`. The try-with-resources `close()`
-performs a `CloseSession` network RPC but swallows (and logs) any failure of
-that RPC so a close-time error never replaces the exception a try-with-resources
-body is already propagating. Call `closeRaw()` explicitly when you need to
-observe the close result or handle a close-time failure.
-
-`MxGatewayClient` and `GalaxyRepositoryClient` implement `AutoCloseable`. For a
-client that owns its channel (built with `connect`), the try-with-resources
-`close()` shuts the channel down and waits up to the configured
-`shutdownTimeout` (default 10 s, independent of `connectTimeout`) for
-termination, forcibly shutting it down on timeout, so in-flight calls and
-Netty event-loop threads are not left running after the block exits. If the
-calling thread is interrupted while waiting, the channel is forcibly shut down
-and the interrupt flag is restored. `closeAndAwaitTermination()` does the same
-but throws `InterruptedException` for callers that want a checked,
-blocking-aware shutdown. `close()` is a no-op for a caller-managed channel.
-
 `MxEventStream` implements `Iterator<MxEvent>` and `AutoCloseable`. Closing it
 cancels the underlying gRPC stream. Canceling or timing out a Java client call
 only stops the client from waiting; it does not abort an in-flight MXAccess COM
-call on the worker STA. Closing an `MxEventStream` *before* the gRPC call has
-attached its observer (a real race when callers cancel immediately after
-subscribing) is safe — the close is replayed in the observer's `beforeStart`
-and the underlying call is cancelled, matching `DeployEventStream` behaviour.
-The event stream uses gRPC's default auto-inbound flow control with a fixed
-1024-element buffer and no client-side flow control: this is the gateway's
-documented fail-fast event-backpressure model, so a consumer that stalls long
-enough to fill the buffer triggers an overflow that cancels the subscription
-and surfaces an `MxGatewayException` from the next `next()` call. Drain events
-promptly and be prepared to resubscribe with a resume cursor.
+call on the worker STA.

-Cancellation of `CompletableFuture` results from `openSessionAsync`,
-`invokeAsync`, `acknowledgeAlarmAsync`, `getLastDeployTimeAsync`,
-`testConnectionAsync`, and `discoverHierarchyAsync` forwards to the underlying
-gRPC call: calling `cancel(true)` on the returned future aborts the in-flight
-RPC instead of merely detaching the future from its result.
+For alarms, `MxGatewayClient` exposes `queryActiveAlarms` (one-shot snapshot),
+`streamAlarms` (returns an `MxGatewayAlarmFeedSubscription` whose iterator
+yields alarm-feed messages from the gateway's central monitor), and
+`acknowledgeAlarm` (ack by full alarm reference with an optional comment and
+ack target). Close the subscription to cancel the underlying gRPC stream.

 ## Galaxy Repository Browse

@@ -154,11 +121,64 @@ The CLI exposes matching subcommands: `galaxy-test`, `galaxy-deploy-time`,
 `--timeout`, and `--json` options as the gateway commands.

 ```powershell
-gradle :mxgateway-cli:run --args="galaxy-test --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
-gradle :mxgateway-cli:run --args="galaxy-deploy-time --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
-gradle :mxgateway-cli:run --args="galaxy-discover --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-test --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-deploy-time --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-discover --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
 ```

+### Browsing lazily
+
+For UI trees or OPC UA bridges, use `browseChildren` to walk one level at a
+time instead of loading the full hierarchy with `discoverHierarchy`. Pass a
+default request for root objects; subsequent calls set `parentGobjectId`,
+`parentTagName`, or `parentContainedPath`. Filter fields match
+`DiscoverHierarchy`. Each response pairs `getChildrenList()` with
+`getChildHasChildrenList()` so you know which nodes to expand. See
+[Galaxy Repository](../../docs/GalaxyRepository.md#browsechildren) for full
+request and filter semantics. This snippet documents the API as it appears once
+the Java client is regenerated on the Windows host.
+
+```java
+BrowseChildrenReply reply = galaxy.browseChildren(
+        BrowseChildrenRequest.newBuilder().build());
+
+List<GalaxyObject> children = reply.getChildrenList();
+List<Boolean> hasChildren = reply.getChildHasChildrenList();
+for (int i = 0; i < children.size(); i++) {
+    System.out.printf("%s expand=%b%n", children.get(i).getTagName(), hasChildren.get(i));
+}
+```
+
+#### High-level walker
+
+For UI trees, the client provides a `LazyBrowseNode` walker that handles
+sibling pagination and the `child_has_children` hint for you:
+
+```java
+MxGatewayClientOptions options = MxGatewayClientOptions.builder()
+        .endpoint("localhost:5000")
+        .apiKey(System.getenv("MXGATEWAY_API_KEY"))
+        .plaintext(true)
+        .build();
+
+try (GalaxyRepositoryClient galaxy = GalaxyRepositoryClient.connect(options)) {
+    List<LazyBrowseNode> roots = galaxy.browse();
+    for (LazyBrowseNode root : roots) {
+        if (root.hasChildrenHint()) {
+            root.expand();
+        }
+        for (LazyBrowseNode child : root.getChildren()) {
+            String kind = child.hasChildrenHint() ? "has children" : "leaf";
+            System.out.println(child.getObject().getTagName() + " (" + kind + ")");
+        }
+    }
+}
+```
+
+`expand` is idempotent — calling it twice fires only one RPC,
+and is safe under concurrent callers. To refresh after a Galaxy redeploy, call
+`browse` again from the root.
+
 ### Watching deploy events

 `GalaxyRepository.WatchDeployEvents` is a server-streaming RPC: the gateway
@@ -206,8 +226,8 @@ The matching CLI subcommand streams events until cancelled (Ctrl+C) and prints
 one line per event in text mode or one JSON object per event with `--json`:

 ```powershell
-gradle :mxgateway-cli:run --args="galaxy-watch --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
-gradle :mxgateway-cli:run --args="galaxy-watch --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --last-seen-deploy-time 2026-04-28T18:30:00Z --limit 5"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-watch --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-watch --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --last-seen-deploy-time 2026-04-28T18:30:00Z --limit 5"
 ```

 ## CLI Usage
@@ -215,14 +235,16 @@ gradle :mxgateway-cli:run --args="galaxy-watch --endpoint localhost:5000 --api-k
 Run the CLI through Gradle:

 ```powershell
-gradle :mxgateway-cli:run --args="version --json"
-gradle :mxgateway-cli:run --args="open-session --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --client-session-name java-cli --json"
-gradle :mxgateway-cli:run --args="register --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --client-name java-cli --json"
-gradle :mxgateway-cli:run --args="add-item --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item TestObject.TestInt --json"
-gradle :mxgateway-cli:run --args="advise --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item-handle 1 --json"
-gradle :mxgateway-cli:run --args="write --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --json"
-gradle :mxgateway-cli:run --args="stream-events --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --limit 1 --json"
-gradle :mxgateway-cli:run --args="smoke --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --item TestObject.TestInt --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="version --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="open-session --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --client-session-name java-cli --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="register --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --client-name java-cli --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="add-item --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item TestObject.TestInt --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="advise --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item-handle 1 --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="write --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item-handle 1 --type int32 --value 123 --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="stream-events --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --limit 1 --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="stream-alarms --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --filter-prefix Galaxy --limit 1 --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="acknowledge-alarm --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --reference \"\\Galaxy\Area001.Pump001.PumpFault\" --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="smoke --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --item TestObject.TestInt --json"
 ```

 The CLI accepts `--api-key`, `--api-key-env`, `--plaintext`, `--ca-file`,
@@ -232,7 +254,7 @@ output redacts API keys.
 Use TLS options for a secured gateway:

 ```powershell
-gradle :mxgateway-cli:run --args="smoke --endpoint mxgateway.example.local:5001 --ca-file C:\certs\mxgateway-ca.pem --server-name-override mxgateway.example.local --api-key-env MXGATEWAY_API_KEY --item TestObject.TestInt --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="smoke --endpoint mxgateway.example.local:5001 --ca-file C:\certs\mxgateway-ca.pem --server-name-override mxgateway.example.local --api-key-env MXGATEWAY_API_KEY --item TestObject.TestInt --json"
 ```

 ## Build And Test
@@ -252,11 +274,11 @@ in-process gRPC behavior, stream cancellation, and CLI parser/output behavior.
 Create local library and CLI artifacts from `clients/java`:

 ```powershell
-gradle :mxgateway-client:jar :mxgateway-cli:installDist
+gradle :zb-mom-ww-mxgateway-client:jar :zb-mom-ww-mxgateway-cli:installDist
 ```

-The library jar is under `mxgateway-client/build/libs`. The installed CLI
-distribution is under `mxgateway-cli/build/install/mxgateway-cli`.
+The library jar is under `zb-mom-ww-mxgateway-client/build/libs`. The installed CLI
+distribution is under `zb-mom-ww-mxgateway-cli/build/install/zb-mom-ww-mxgateway-cli`.

 ## Integration Checks

@@ -267,9 +289,40 @@ $env:MXGATEWAY_INTEGRATION = '1'
 $env:MXGATEWAY_ENDPOINT = 'localhost:5000'
 $env:MXGATEWAY_API_KEY = '<gateway-api-key>'
 $env:MXGATEWAY_TEST_ITEM = 'TestObject.TestInt'
-gradle :mxgateway-cli:run --args="smoke --endpoint $env:MXGATEWAY_ENDPOINT --plaintext --api-key-env MXGATEWAY_API_KEY --item $env:MXGATEWAY_TEST_ITEM --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="smoke --endpoint $env:MXGATEWAY_ENDPOINT --plaintext --api-key-env MXGATEWAY_API_KEY --item $env:MXGATEWAY_TEST_ITEM --json"
 ```

+## Installing from the Gitea Maven repository
+
+The client publishes to the internal Gitea Maven repository at
+`https://gitea.dohertylan.com/api/packages/dohertj2/maven`.
+
+In your consumer project's `build.gradle`:
+
+````groovy
+repositories {
+    maven {
+        url 'https://gitea.dohertylan.com/api/packages/dohertj2/maven'
+        credentials {
+            username = System.getenv('GITEA_USERNAME')
+            password = System.getenv('GITEA_TOKEN')
+        }
+    }
+}
+
+dependencies {
+    implementation 'com.zb.mom.ww.mxgateway:zb-mom-ww-mxgateway-client:0.1.0'
+}
+````
+
+To publish a new version from this repo:
+
+````bash
+export GITEA_USERNAME=dohertj2
+export GITEA_TOKEN=<your-gitea-token>
+gradle :zb-mom-ww-mxgateway-client:publish
+````
+
 ## Related Documentation

 - [Client Packaging](../../docs/ClientPackaging.md)
@@ -12,7 +12,7 @@ ext {
 }

 subprojects {
-    group = 'com.dohertylan.mxgateway'
+    group = 'com.zb.mom.ww.mxgateway'
    version = '0.1.0'

    pluginManager.withPlugin('java') {
@@ -37,4 +37,44 @@ subprojects {
            testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
        }
    }
+
+    pluginManager.withPlugin('maven-publish') {
+        publishing {
+            publications {
+                maven(MavenPublication) {
+                    from components.java
+                    pom {
+                        url = 'https://gitea.dohertylan.com/dohertj2/mxaccessgw'
+                        description = 'MxAccessGateway Java client'
+                        scm {
+                            url = 'https://gitea.dohertylan.com/dohertj2/mxaccessgw'
+                            connection = 'scm:git:https://gitea.dohertylan.com/dohertj2/mxaccessgw.git'
+                        }
+                        developers {
+                            developer {
+                                id = 'dohertj2'
+                                name = 'Joseph Doherty'
+                            }
+                        }
+                        licenses {
+                            license {
+                                name = 'Proprietary'
+                                distribution = 'repo'
+                            }
+                        }
+                    }
+                }
+            }
+            repositories {
+                maven {
+                    name = 'GiteaPackages'
+                    url = 'https://gitea.dohertylan.com/api/packages/dohertj2/maven'
+                    credentials {
+                        username = System.getenv('GITEA_USERNAME') ?: ''
+                        password = System.getenv('GITEA_TOKEN') ?: ''
+                    }
+                }
+            }
+        }
+    }
 }
@@ -1,65 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import galaxy_repository.v1.GalaxyRepositoryOuterClass.DeployEvent;
-import galaxy_repository.v1.GalaxyRepositoryOuterClass.WatchDeployEventsRequest;
-import io.grpc.stub.ClientCallStreamObserver;
-import io.grpc.stub.ClientResponseObserver;
-import io.grpc.stub.StreamObserver;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicReference;
-
-/**
- * Cancellable handle returned by the async {@code watchDeployEvents} variant.
- * Mirrors {@link MxGatewayEventSubscription} but for the Galaxy Repository
- * deploy-event stream.
- */
-public final class DeployEventSubscription implements AutoCloseable {
-    private final AtomicReference<ClientCallStreamObserver<WatchDeployEventsRequest>> requestStream =
-            new AtomicReference<>();
-    private final AtomicBoolean cancelled = new AtomicBoolean();
-
-    ClientResponseObserver<WatchDeployEventsRequest, DeployEvent> wrap(StreamObserver<DeployEvent> observer) {
-        return new ClientResponseObserver<>() {
-            @Override
-            public void beforeStart(ClientCallStreamObserver<WatchDeployEventsRequest> stream) {
-                requestStream.set(stream);
-                if (cancelled.get()) {
-                    stream.cancel("client cancelled deploy event stream", null);
-                }
-            }
-
-            @Override
-            public void onNext(DeployEvent value) {
-                observer.onNext(value);
-            }
-
-            @Override
-            public void onError(Throwable error) {
-                observer.onError(error);
-            }
-
-            @Override
-            public void onCompleted() {
-                observer.onCompleted();
-            }
-        };
-    }
-
-    /**
-     * Cancels the underlying gRPC call. Safe to invoke before the call has
-     * started; cancellation is recorded and applied as soon as the stream
-     * attaches.
-     */
-    public void cancel() {
-        cancelled.set(true);
-        ClientCallStreamObserver<WatchDeployEventsRequest> stream = requestStream.get();
-        if (stream != null) {
-            stream.cancel("client cancelled deploy event stream", null);
-        }
-    }
-
-    @Override
-    public void close() {
-        cancel();
-    }
-}
@@ -1,67 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import io.grpc.stub.ClientCallStreamObserver;
-import io.grpc.stub.ClientResponseObserver;
-import io.grpc.stub.StreamObserver;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicReference;
-import mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage;
-import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;
-
-/**
- * Cancellable handle returned by {@code streamAlarms}.
- *
- * <p>Wraps a caller-supplied {@link StreamObserver} and exposes a
- * {@link #cancel()} entry point that aborts the underlying gRPC call. The
- * subscription also implements {@link AutoCloseable} so it can participate in
- * try-with-resources blocks.
- */
-public final class MxGatewayAlarmFeedSubscription implements AutoCloseable {
-    private final AtomicReference<ClientCallStreamObserver<StreamAlarmsRequest>> requestStream = new AtomicReference<>();
-    private final AtomicBoolean cancelled = new AtomicBoolean();
-
-    ClientResponseObserver<StreamAlarmsRequest, AlarmFeedMessage> wrap(StreamObserver<AlarmFeedMessage> observer) {
-        return new ClientResponseObserver<>() {
-            @Override
-            public void beforeStart(ClientCallStreamObserver<StreamAlarmsRequest> stream) {
-                requestStream.set(stream);
-                if (cancelled.get()) {
-                    stream.cancel("client cancelled alarm feed", null);
-                }
-            }
-
-            @Override
-            public void onNext(AlarmFeedMessage value) {
-                observer.onNext(value);
-            }
-
-            @Override
-            public void onError(Throwable error) {
-                observer.onError(error);
-            }
-
-            @Override
-            public void onCompleted() {
-                observer.onCompleted();
-            }
-        };
-    }
-
-    /**
-     * Cancels the underlying gRPC call. Safe to invoke before the call has
-     * started; cancellation is recorded and applied as soon as the stream
-     * attaches.
-     */
-    public void cancel() {
-        cancelled.set(true);
-        ClientCallStreamObserver<StreamAlarmsRequest> stream = requestStream.get();
-        if (stream != null) {
-            stream.cancel("client cancelled alarm feed", null);
-        }
-    }
-
-    @Override
-    public void close() {
-        cancel();
-    }
-}
@@ -1,321 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import com.google.common.util.concurrent.FutureCallback;
-import com.google.common.util.concurrent.Futures;
-import com.google.common.util.concurrent.ListenableFuture;
-import com.google.common.util.concurrent.MoreExecutors;
-import io.grpc.ManagedChannel;
-import io.grpc.netty.shaded.io.grpc.netty.GrpcSslContexts;
-import io.grpc.netty.shaded.io.grpc.netty.NettyChannelBuilder;
-import io.grpc.stub.AbstractStub;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.TimeUnit;
-import java.util.function.Function;
-import javax.net.ssl.SSLException;
-
-/**
- * Shared channel-builder and future-adaptor helpers used by both
- * {@link MxGatewayClient} and {@link GalaxyRepositoryClient}.
- *
- * <p>Extracted so transport construction, per-call deadlines, and the
- * {@link ListenableFuture}-to-{@link CompletableFuture} bridge live in one
- * place instead of being duplicated verbatim across the two clients.
- */
-final class MxGatewayChannels {
-    private MxGatewayChannels() {
-    }
-
-    /**
-     * Builds a Netty managed channel from the supplied options, applying the
-     * connect timeout, message-size limit, and the configured transport
-     * security mode (plaintext, custom CA trust, or system trust).
-     *
-     * @param options the client options carrying endpoint and transport config
-     * @param tlsErrorPrefix a human-readable prefix for the {@link MxGatewayException}
-     *     thrown when a custom CA certificate cannot be loaded
-     * @return a new managed channel; the caller owns its lifecycle
-     */
-    static ManagedChannel createChannel(MxGatewayClientOptions options, String tlsErrorPrefix) {
-        NettyChannelBuilder builder = NettyChannelBuilder.forTarget(options.endpoint())
-                .maxInboundMessageSize(options.maxGrpcMessageBytes());
-        if (!options.connectTimeout().isNegative()) {
-            builder.withOption(
-                    io.grpc.netty.shaded.io.netty.channel.ChannelOption.CONNECT_TIMEOUT_MILLIS,
-                    Math.toIntExact(options.connectTimeout().toMillis()));
-        }
-        if (options.plaintext()) {
-            builder.usePlaintext();
-        } else if (options.caCertificatePath() != null) {
-            try {
-                builder.sslContext(GrpcSslContexts.forClient()
-                        .trustManager(options.caCertificatePath().toFile())
-                        .build());
-            } catch (SSLException | RuntimeException error) {
-                // SSLException covers handshake-context failures; RuntimeException
-                // (IllegalArgumentException wrapping CertificateException) covers a
-                // missing or unreadable CA file. Either way callers see one typed
-                // failure instead of a raw, unwrapped exception leaking out.
-                throw new MxGatewayException(tlsErrorPrefix, error);
-            }
-        } else {
-            builder.useTransportSecurity();
-        }
-        if (!options.serverNameOverride().isBlank()) {
-            builder.overrideAuthority(options.serverNameOverride());
-        }
-        return builder.build();
-    }
-
-    /**
-     * Applies the configured per-call deadline to a unary stub.
-     *
-     * @param stub the stub to decorate
-     * @param options the client options carrying the call timeout
-     * @param <T> the concrete stub type
-     * @return the stub with the call deadline applied, or the stub unchanged
-     *     when the call timeout is negative (disabled)
-     */
-    static <T extends AbstractStub<T>> T withDeadline(T stub, MxGatewayClientOptions options) {
-        if (options.callTimeout().isNegative()) {
-            return stub;
-        }
-        return stub.withDeadlineAfter(options.callTimeout().toNanos(), TimeUnit.NANOSECONDS);
-    }
-
-    /**
-     * Applies the configured streaming deadline to a streaming stub.
-     *
-     * @param stub the stub to decorate
-     * @param options the client options carrying the stream timeout
-     * @param <T> the concrete stub type
-     * @return the stub with the stream deadline applied, or the stub unchanged
-     *     when the stream timeout is unset or negative (disabled)
-     */
-    static <T extends AbstractStub<T>> T withStreamDeadline(T stub, MxGatewayClientOptions options) {
-        if (options.streamTimeout() == null || options.streamTimeout().isNegative()) {
-            return stub;
-        }
-        return stub.withDeadlineAfter(options.streamTimeout().toNanos(), TimeUnit.NANOSECONDS);
-    }
-
-    /**
-     * Shuts a client-owned channel down and waits up to the configured
-     * {@link MxGatewayClientOptions#shutdownTimeout()} for graceful
-     * termination, forcing {@code shutdownNow()} on timeout. If the calling
-     * thread is interrupted while waiting, the channel is forcibly shut down
-     * and the thread's interrupt flag is restored — this matches the
-     * try-with-resources {@code close()} contract that cannot throw a checked
-     * exception.
-     *
-     * <p>No-op when {@code ownedChannel} is {@code null} (i.e. the caller owns
-     * the channel lifecycle on a borrowed channel).
-     *
-     * @param ownedChannel the channel to shut down, may be {@code null}
-     * @param options the client options carrying the shutdown timeout
-     */
-    static void shutdown(ManagedChannel ownedChannel, MxGatewayClientOptions options) {
-        if (ownedChannel == null) {
-            return;
-        }
-        ownedChannel.shutdown();
-        try {
-            if (!ownedChannel.awaitTermination(options.shutdownTimeout().toMillis(), TimeUnit.MILLISECONDS)) {
-                ownedChannel.shutdownNow();
-            }
-        } catch (InterruptedException error) {
-            ownedChannel.shutdownNow();
-            Thread.currentThread().interrupt();
-        }
-    }
-
-    /**
-     * Shuts a client-owned channel down and waits up to the configured
-     * {@link MxGatewayClientOptions#shutdownTimeout()} for termination,
-     * forcing {@code shutdownNow()} on timeout. Throws
-     * {@link InterruptedException} when the calling thread is interrupted —
-     * for callers that want a checked, blocking-aware shutdown.
-     *
-     * <p>No-op when {@code ownedChannel} is {@code null}.
-     *
-     * @param ownedChannel the channel to shut down, may be {@code null}
-     * @param options the client options carrying the shutdown timeout
-     * @throws InterruptedException if the calling thread is interrupted while waiting
-     */
-    static void shutdownAndAwaitTermination(ManagedChannel ownedChannel, MxGatewayClientOptions options)
-            throws InterruptedException {
-        if (ownedChannel == null) {
-            return;
-        }
-        ownedChannel.shutdown();
-        if (!ownedChannel.awaitTermination(options.shutdownTimeout().toMillis(), TimeUnit.MILLISECONDS)) {
-            ownedChannel.shutdownNow();
-        }
-    }
-
-    /**
-     * Bridges a Guava {@link ListenableFuture} to a {@link CompletableFuture},
-     * normalising any failure through {@link MxGatewayErrors#fromGrpc} so the
-     * async error surface matches the synchronous methods. Cancelling the
-     * returned future cancels the source RPC.
-     *
-     * <p><strong>Cancellation contract:</strong> the returned future is a
-     * {@link CancellingCompletableFuture} that overrides
-     * {@link CompletableFuture#cancel(boolean)} so cancelling the
-     * <em>direct return value</em> forwards to the source
-     * {@link ListenableFuture}, aborting the underlying gRPC call. This is the
-     * fix for Client.Java-015.
-     *
-     * <p><strong>Important — derived stages do <em>not</em> propagate
-     * cancellation upstream.</strong> Calling
-     * {@code cancel(...)} on a future obtained via
-     * {@code thenApply}/{@code thenCompose}/{@code thenAccept}/{@code whenComplete}
-     * of the value returned by this method only marks <em>that</em> derived stage
-     * as cancelled; it does <strong>not</strong> propagate back to this
-     * {@code CancellingCompletableFuture}, so the source RPC continues until its
-     * deadline expires. {@link CompletableFuture#thenApply} (and the other
-     * chaining methods) deliberately do not forward cancellation to the upstream
-     * stage they were derived from.
-     *
-     * <p>If a caller needs cancellation through a chained pipeline, either:
-     * <ul>
-     *   <li>use the {@link #toCompletable(ListenableFuture, String, Function)}
-     *       overload below, which inlines a validator into the
-     *       {@code FutureCallback} so the user-visible future is the same
-     *       future cancellation is bound to (this is what the {@code *Async}
-     *       methods on {@link MxGatewayClient} and the unary methods on
-     *       {@link GalaxyRepositoryClient} do); or</li>
-     *   <li>follow {@link GalaxyRepositoryClient#discoverHierarchyAsync}'s
-     *       pattern of returning a custom {@link CompletableFuture} subclass
-     *       that tracks the current in-flight stage via an
-     *       {@link java.util.concurrent.atomic.AtomicReference} and forwards
-     *       {@code cancel(...)} to it (necessary when chaining
-     *       {@code thenCompose} stages across paged calls).</li>
-     * </ul>
-     *
-     * @param source the gRPC future-stub result
-     * @param operation the operation name used in normalised error messages
-     * @param <T> the reply type
-     * @return a completable future mirroring the source
-     */
-    static <T> CompletableFuture<T> toCompletable(ListenableFuture<T> source, String operation) {
-        CancellingCompletableFuture<T> target = new CancellingCompletableFuture<>(source);
-        Futures.addCallback(
-                source,
-                new FutureCallback<>() {
-                    @Override
-                    public void onSuccess(T result) {
-                        target.complete(result);
-                    }
-
-                    @Override
-                    public void onFailure(Throwable error) {
-                        if (error instanceof RuntimeException runtimeException) {
-                            target.completeExceptionally(MxGatewayErrors.fromGrpc(operation, runtimeException));
-                            return;
-                        }
-                        target.completeExceptionally(error);
-                    }
-                },
-                MoreExecutors.directExecutor());
-        return target;
-    }
-
-    /**
-     * Bridges a Guava {@link ListenableFuture} to a {@link CompletableFuture}
-     * and applies {@code validator} to the reply inline (i.e. without a
-     * downstream {@code thenApply}), so the user-visible future is the same
-     * future cancellation is bound to. Any non-{@link MxGatewayException}
-     * {@link RuntimeException} thrown by {@code validator} is routed through
-     * {@link MxGatewayErrors#fromGrpc} to match the synchronous error surface.
-     *
-     * <p>This overload exists because the prior {@code toCompletable(...)
-     * .thenApply(validator)} pattern broke cancellation propagation: the
-     * future returned by {@code thenApply} is a new stage whose cancellation
-     * does not propagate to the underlying gRPC call. Using this overload, the
-     * single returned future is the one users hold, so calling {@code cancel}
-     * on it forwards to the source RPC.
-     *
-     * @param source the gRPC future-stub result
-     * @param operation the operation name used in normalised error messages
-     * @param validator the validating/transforming function applied to the reply
-     * @param <T> the reply type
-     * @param <R> the validated/transformed result type
-     * @return a completable future mirroring the validated source
-     */
-    static <T, R> CompletableFuture<R> toCompletable(
-            ListenableFuture<T> source, String operation, Function<T, R> validator) {
-        CancellingCompletableFuture<R> target = new CancellingCompletableFuture<>(source);
-        Futures.addCallback(
-                source,
-                new FutureCallback<>() {
-                    @Override
-                    public void onSuccess(T result) {
-                        try {
-                            target.complete(validator.apply(result));
-                        } catch (MxGatewayException error) {
-                            target.completeExceptionally(error);
-                        } catch (RuntimeException error) {
-                            target.completeExceptionally(MxGatewayErrors.fromGrpc(operation, error));
-                        }
-                    }
-
-                    @Override
-                    public void onFailure(Throwable error) {
-                        if (error instanceof RuntimeException runtimeException) {
-                            target.completeExceptionally(MxGatewayErrors.fromGrpc(operation, runtimeException));
-                            return;
-                        }
-                        target.completeExceptionally(error);
-                    }
-                },
-                MoreExecutors.directExecutor());
-        return target;
-    }
-
-    /**
-     * {@link CompletableFuture} subclass that forwards {@link #cancel(boolean)}
-     * to a backing {@link ListenableFuture}. Used by {@link #toCompletable} so
-     * cancelling the user-visible future cancels the underlying gRPC call.
-     */
-    static final class CancellingCompletableFuture<T> extends CompletableFuture<T> {
-        private final ListenableFuture<?> source;
-
-        CancellingCompletableFuture(ListenableFuture<?> source) {
-            this.source = source;
-        }
-
-        @Override
-        public boolean cancel(boolean mayInterruptIfRunning) {
-            boolean cancelled = super.cancel(mayInterruptIfRunning);
-            // Always forward; the source future is idempotent on cancel and the
-            // user contract is that cancelling the future cancels the RPC.
-            source.cancel(mayInterruptIfRunning);
-            return cancelled;
-        }
-    }
-
-    /**
-     * Adapts a reply-validating function for use inside {@code thenApply} so
-     * any non-{@link MxGatewayException} {@link RuntimeException} it raises is
-     * routed through {@link MxGatewayErrors#fromGrpc}. This keeps the async
-     * error surface consistent with the synchronous methods, which normalise
-     * failures with a {@code try/catch}.
-     *
-     * @param operation the operation name used in normalised error messages
-     * @param validator the validating/transforming function applied to the reply
-     * @param <T> the reply type
-     * @param <R> the result type
-     * @return a function suitable for {@link CompletableFuture#thenApply}
-     */
-    static <T, R> Function<T, R> normalisingValidator(String operation, Function<T, R> validator) {
-        return reply -> {
-            try {
-                return validator.apply(reply);
-            } catch (MxGatewayException error) {
-                throw error;
-            } catch (RuntimeException error) {
-                throw MxGatewayErrors.fromGrpc(operation, error);
-            }
-        };
-    }
-}
@@ -1,67 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import io.grpc.stub.ClientCallStreamObserver;
-import io.grpc.stub.ClientResponseObserver;
-import io.grpc.stub.StreamObserver;
-import java.util.concurrent.atomic.AtomicReference;
-import java.util.concurrent.atomic.AtomicBoolean;
-import mxaccess_gateway.v1.MxaccessGateway.MxEvent;
-import mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest;
-
-/**
- * Cancellable handle returned by the async {@code streamEvents} variant.
- *
- * <p>Wraps a caller-supplied {@link StreamObserver} and exposes a
- * {@link #cancel()} entry point that aborts the underlying gRPC call. The
- * subscription also implements {@link AutoCloseable} so it can participate in
- * try-with-resources blocks.
- */
-public final class MxGatewayEventSubscription implements AutoCloseable {
-    private final AtomicReference<ClientCallStreamObserver<StreamEventsRequest>> requestStream = new AtomicReference<>();
-    private final AtomicBoolean cancelled = new AtomicBoolean();
-
-    ClientResponseObserver<StreamEventsRequest, MxEvent> wrap(StreamObserver<MxEvent> observer) {
-        return new ClientResponseObserver<>() {
-            @Override
-            public void beforeStart(ClientCallStreamObserver<StreamEventsRequest> stream) {
-                requestStream.set(stream);
-                if (cancelled.get()) {
-                    stream.cancel("client cancelled event stream", null);
-                }
-            }
-
-            @Override
-            public void onNext(MxEvent value) {
-                observer.onNext(value);
-            }
-
-            @Override
-            public void onError(Throwable error) {
-                observer.onError(error);
-            }
-
-            @Override
-            public void onCompleted() {
-                observer.onCompleted();
-            }
-        };
-    }
-
-    /**
-     * Cancels the underlying gRPC call. Safe to invoke before the call has
-     * started; cancellation is recorded and applied as soon as the stream
-     * attaches.
-     */
-    public void cancel() {
-        cancelled.set(true);
-        ClientCallStreamObserver<StreamEventsRequest> stream = requestStream.get();
-        if (stream != null) {
-            stream.cancel("client cancelled event stream", null);
-        }
-    }
-
-    @Override
-    public void close() {
-        cancel();
-    }
-}
@@ -1,81 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import java.util.regex.Pattern;
-
-/**
- * Helpers for redacting secrets such as gateway API keys from log output.
- *
- * <p>API keys must never reach logs in plaintext. The methods on this class
- * produce shortened, masked forms safe for diagnostic messages.
- */
-public final class MxGatewaySecrets {
-    // Match any gateway-shaped credential anywhere in the string, regardless of
-    // surrounding punctuation: quoted, colon/comma-delimited, embedded in URLs
-    // or parens. The underscore-separated character class also covers a
-    // trailing hyphen in case a future key format introduces one.
-    private static final Pattern MXGW_TOKEN = Pattern.compile("mxgw_[A-Za-z0-9_-]+");
-    // Mask the token after a Bearer marker as a unit so callers cannot
-    // accidentally leak the secret when the surrounding text is a header-style
-    // string (e.g. "Bearer mxgw_id_secret").
-    private static final Pattern BEARER_TOKEN = Pattern.compile("(?i)bearer\\s+\\S+");
-
-    private MxGatewaySecrets() {
-    }
-
-    /**
-     * Redacts the secret portion of an API key, leaving only the non-secret
-     * key identifier visible so the value remains comparable in logs.
-     *
-     * <p>A gateway API key has the form {@code mxgw_<key-id>_<secret>}. Only the
-     * {@code mxgw_<key-id>_} prefix is non-secret; everything after the second
-     * underscore is the secret and is masked entirely &mdash; no leading or
-     * trailing characters of the secret are echoed. Tokens that do not match
-     * the gateway shape are masked completely as {@code "<redacted>"}.
-     *
-     * @param apiKey the API key to redact, may be {@code null} or empty
-     * @return an empty string for {@code null}/empty input, {@code "<redacted>"}
-     *         for non-gateway-shaped tokens, or {@code mxgw_<key-id>_***} with the
-     *         secret masked for gateway-shaped keys
-     */
-    public static String redactApiKey(String apiKey) {
-        if (apiKey == null || apiKey.isEmpty()) {
-            return "";
-        }
-
-        // Gateway keys are mxgw_<key-id>_<secret>; keep only the non-secret prefix.
-        if (apiKey.startsWith("mxgw_")) {
-            int secretSeparator = apiKey.indexOf('_', "mxgw_".length());
-            if (secretSeparator >= 0 && secretSeparator < apiKey.length() - 1) {
-                return apiKey.substring(0, secretSeparator + 1) + "***";
-            }
-        }
-
-        // Anything else is treated as wholly secret — reveal nothing.
-        return "<redacted>";
-    }
-
-    /**
-     * Replaces gateway-style credential tokens inside a free-form string with a
-     * redaction placeholder.
-     *
-     * <p>Matches any {@code mxgw_<...>} token anywhere in the string,
-     * irrespective of surrounding punctuation (whitespace, colons, commas,
-     * single/double quotes, parentheses, embedded URL paths). Also masks the
-     * argument of an authorization-header style {@code Bearer <token>} marker
-     * as a unit so the token cannot leak through when the surrounding string
-     * is a raw header value.
-     *
-     * @param value the string to scrub, may be {@code null}
-     * @return an empty string for {@code null}, the original value when blank,
-     *         or the value with credential tokens replaced by {@code "<redacted>"}
-     */
-    public static String redactCredentials(String value) {
-        if (value == null || value.isBlank()) {
-            return value == null ? "" : value;
-        }
-
-        String scrubbed = MXGW_TOKEN.matcher(value).replaceAll("<redacted>");
-        scrubbed = BEARER_TOKEN.matcher(scrubbed).replaceAll("Bearer <redacted>");
-        return scrubbed;
-    }
-}
@@ -1,182 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import io.grpc.CallOptions;
-import io.grpc.ClientCall;
-import io.grpc.ConnectivityState;
-import io.grpc.ManagedChannel;
-import io.grpc.MethodDescriptor;
-import java.time.Duration;
-import java.util.concurrent.TimeUnit;
-import org.junit.jupiter.api.Test;
-
-/**
- * Regression tests for the second-pass Low-severity Client.Java findings
- * Client.Java-016, Client.Java-019, and the shared shutdown helpers extracted
- * to {@link MxGatewayChannels}.
- */
-final class MxGatewayLowFindingsIITests {
-
-    // --- Client.Java-019: shutdown timeout is independent of connect timeout ---
-
-    @Test
-    void shutdownAndAwaitTerminationHonoursShutdownTimeoutNotConnectTimeout() throws Exception {
-        // The historical bug: close() used connectTimeout as the awaitTermination
-        // deadline, so a small connectTimeout forced a premature shutdownNow()
-        // on in-flight calls. The fix uses a dedicated shutdownTimeout. This
-        // test verifies the helper waits up to shutdownTimeout (1s) even when
-        // connectTimeout is set to a tiny value (50ms).
-        RecordingChannel channel = new RecordingChannel(/* terminatesAfterMillis = */ 200);
-        MxGatewayClientOptions options = MxGatewayClientOptions.builder()
-                .endpoint("in-process")
-                .plaintext(true)
-                .connectTimeout(Duration.ofMillis(50))
-                .shutdownTimeout(Duration.ofSeconds(1))
-                .build();
-
-        long start = System.nanoTime();
-        MxGatewayChannels.shutdownAndAwaitTermination(channel, options);
-        long elapsedMillis = (System.nanoTime() - start) / 1_000_000L;
-
-        // The channel finished orderly termination within the shutdown timeout
-        // window, so shutdownNow() must NOT have been called. With the old
-        // implementation a 50ms connect-timeout-as-shutdown-deadline would
-        // have escalated to shutdownNow() before the channel's 200ms graceful
-        // termination completed.
-        assertTrue(channel.shutdownCalled, "shutdown() must be called");
-        assertFalse(
-                channel.shutdownNowCalled,
-                "graceful termination finished within shutdownTimeout; shutdownNow() must not have been called");
-        // Allow ample slack for build-machine variance but assert we waited at
-        // least the channel's graceful-termination window.
-        assertTrue(elapsedMillis >= 150, "should have waited for graceful termination, elapsed=" + elapsedMillis);
-    }
-
-    @Test
-    void shutdownEscalatesToShutdownNowWhenTimeoutExceeded() {
-        // The other half of the contract: a channel that does not terminate
-        // within the shutdownTimeout window must be forcibly shut down.
-        RecordingChannel channel = new RecordingChannel(/* terminatesAfterMillis = */ 5_000);
-        MxGatewayClientOptions options = MxGatewayClientOptions.builder()
-                .endpoint("in-process")
-                .plaintext(true)
-                .shutdownTimeout(Duration.ofMillis(100))
-                .build();
-
-        MxGatewayChannels.shutdown(channel, options);
-
-        assertTrue(channel.shutdownCalled);
-        assertTrue(channel.shutdownNowCalled, "stuck channel must be forcibly shut down");
-    }
-
-    @Test
-    void shutdownTimeoutDefaultIsTenSecondsIndependentOfConnectTimeout() {
-        MxGatewayClientOptions defaults = MxGatewayClientOptions.builder()
-                .endpoint("in-process")
-                .build();
-        // Default is 10s; an unset connectTimeout-of-10s default coincides but
-        // the two are now independent options.
-        assertEquals(Duration.ofSeconds(10), defaults.shutdownTimeout());
-
-        MxGatewayClientOptions tinyConnect = MxGatewayClientOptions.builder()
-                .endpoint("in-process")
-                .connectTimeout(Duration.ofMillis(500))
-                .build();
-        assertEquals(Duration.ofSeconds(10), tinyConnect.shutdownTimeout(),
-                "shutdownTimeout default is independent of connectTimeout");
-    }
-
-    // --- Client.Java-016: shared shutdown helpers behave identically for both clients ---
-
-    @Test
-    void sharedShutdownHelperIsNoOpForNullChannel() throws Exception {
-        MxGatewayClientOptions options = MxGatewayClientOptions.builder()
-                .endpoint("in-process")
-                .plaintext(true)
-                .shutdownTimeout(Duration.ofMillis(50))
-                .build();
-        // Both helpers must tolerate a null owned-channel (caller-managed channel case).
-        MxGatewayChannels.shutdown(null, options);
-        MxGatewayChannels.shutdownAndAwaitTermination(null, options);
-    }
-
-    /**
-     * Test double for {@link ManagedChannel} that records {@code shutdown}/
-     * {@code shutdownNow} invocations and simulates an orderly termination
-     * after a configurable delay. Avoids the heavy in-process gRPC machinery —
-     * the shutdown helpers only touch the three lifecycle methods.
-     */
-    private static final class RecordingChannel extends ManagedChannel {
-        private final long terminatesAfterMillis;
-        private final long createdAtNanos;
-        private volatile boolean shutdownCalled;
-        private volatile boolean shutdownNowCalled;
-
-        RecordingChannel(long terminatesAfterMillis) {
-            this.terminatesAfterMillis = terminatesAfterMillis;
-            this.createdAtNanos = System.nanoTime();
-        }
-
-        @Override
-        public ManagedChannel shutdown() {
-            shutdownCalled = true;
-            return this;
-        }
-
-        @Override
-        public boolean isShutdown() {
-            return shutdownCalled || shutdownNowCalled;
-        }
-
-        @Override
-        public boolean isTerminated() {
-            if (shutdownNowCalled) {
-                return true;
-            }
-            if (!shutdownCalled) {
-                return false;
-            }
-            long elapsed = (System.nanoTime() - createdAtNanos) / 1_000_000L;
-            return elapsed >= terminatesAfterMillis;
-        }
-
-        @Override
-        public ManagedChannel shutdownNow() {
-            shutdownNowCalled = true;
-            return this;
-        }
-
-        @Override
-        public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException {
-            long deadlineNanos = System.nanoTime() + unit.toNanos(timeout);
-            while (System.nanoTime() < deadlineNanos) {
-                if (isTerminated()) {
-                    return true;
-                }
-                long remaining = Math.max(1, (deadlineNanos - System.nanoTime()) / 1_000_000L);
-                Thread.sleep(Math.min(remaining, 10));
-            }
-            return isTerminated();
-        }
-
-        @Override
-        public <RequestT, ResponseT> ClientCall<RequestT, ResponseT> newCall(
-                MethodDescriptor<RequestT, ResponseT> methodDescriptor, CallOptions callOptions) {
-            throw new UnsupportedOperationException("no RPCs are issued in shutdown tests");
-        }
-
-        @Override
-        public String authority() {
-            return "in-process";
-        }
-
-        @Override
-        public ConnectivityState getState(boolean requestConnection) {
-            return ConnectivityState.IDLE;
-        }
-    }
-
-}
@@ -1,509 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import io.grpc.ManagedChannel;
-import io.grpc.Server;
-import io.grpc.Status;
-import io.grpc.inprocess.InProcessChannelBuilder;
-import io.grpc.inprocess.InProcessServerBuilder;
-import io.grpc.stub.ClientCallStreamObserver;
-import io.grpc.stub.ClientResponseObserver;
-import io.grpc.stub.StreamObserver;
-import java.nio.file.Path;
-import java.time.Duration;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.UUID;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CompletionException;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.atomic.AtomicReference;
-import mxaccess_gateway.v1.MxAccessGatewayGrpc;
-import mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmReply;
-import mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmRequest;
-import mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot;
-import mxaccess_gateway.v1.MxaccessGateway.AlarmConditionState;
-import mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage;
-import mxaccess_gateway.v1.MxaccessGateway.MxEvent;
-import mxaccess_gateway.v1.MxaccessGateway.ProtocolStatus;
-import mxaccess_gateway.v1.MxaccessGateway.ProtocolStatusCode;
-import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;
-import mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest;
-import org.junit.jupiter.api.Test;
-
-/**
- * Regression tests for the Low-severity Client.Java code-review findings
- * (Client.Java-006 through Client.Java-012). Covers the alarm RPC surface,
- * async streaming/subscription cancellation, queue overflow, and TLS-config
- * construction that Client.Java-007 reports as untested.
- */
-final class MxGatewayLowFindingsTests {
-
-    // --- Client.Java-007: AcknowledgeAlarm RPC coverage ---
-
-    @Test
-    void acknowledgeAlarmReturnsReplyAndSendsAuthMetadata() throws Exception {
-        AtomicReference<String> authorization = new AtomicReference<>();
-        AtomicReference<AcknowledgeAlarmRequest> seen = new AtomicReference<>();
-        TestService service = new TestService() {
-            @Override
-            public void acknowledgeAlarm(
-                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
-                seen.set(request);
-                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setProtocolStatus(ok())
-                        .setDiagnosticMessage("acked")
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service, "mxgw_keyid_secret", authorization)) {
-            AcknowledgeAlarmReply reply = harness.client().acknowledgeAlarm(AcknowledgeAlarmRequest.newBuilder()
-                    .setAlarmFullReference("Area1.Pump.PV.HiHi")
-                    .setComment("operator note")
-                    .build());
-            assertEquals("acked", reply.getDiagnosticMessage());
-            assertEquals("Area1.Pump.PV.HiHi", seen.get().getAlarmFullReference());
-            assertEquals("Bearer mxgw_keyid_secret", authorization.get());
-        }
-    }
-
-    @Test
-    void acknowledgeAlarmThrowsTypedExceptionOnProtocolFailure() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void acknowledgeAlarm(
-                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
-                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setProtocolStatus(ProtocolStatus.newBuilder()
-                                .setCode(ProtocolStatusCode.PROTOCOL_STATUS_CODE_SESSION_NOT_FOUND))
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            assertThrows(
-                    MxGatewayException.class,
-                    () -> harness.client().acknowledgeAlarm(AcknowledgeAlarmRequest.newBuilder()
-                            .setAlarmFullReference("Area1.Pump.PV.HiHi")
-                            .build()));
-        }
-    }
-
-    @Test
-    void acknowledgeAlarmAsyncCompletesWithReply() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void acknowledgeAlarm(
-                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
-                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setProtocolStatus(ok())
-                        .setDiagnosticMessage("async-acked")
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            CompletableFuture<AcknowledgeAlarmReply> future = harness.client()
-                    .acknowledgeAlarmAsync(AcknowledgeAlarmRequest.newBuilder()
-                            .setAlarmFullReference("Area1.Pump.PV.HiHi")
-                            .build());
-            assertEquals("async-acked", future.get(5, TimeUnit.SECONDS).getDiagnosticMessage());
-        }
-    }
-
-    @Test
-    void acknowledgeAlarmAsyncFailsExceptionallyWithTypedException() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void acknowledgeAlarm(
-                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
-                responseObserver.onError(Status.UNAVAILABLE.withDescription("worker down").asRuntimeException());
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            CompletableFuture<AcknowledgeAlarmReply> future = harness.client()
-                    .acknowledgeAlarmAsync(AcknowledgeAlarmRequest.newBuilder()
-                            .setAlarmFullReference("Area1.Pump.PV.HiHi")
-                            .build());
-            ExecutionException error = assertThrows(
-                    ExecutionException.class, () -> future.get(5, TimeUnit.SECONDS));
-            assertTrue(error.getCause() instanceof MxGatewayException, () -> String.valueOf(error.getCause()));
-        }
-    }
-
-    // --- Client.Java-007: StreamAlarms RPC + subscription coverage ---
-
-    @Test
-    void streamAlarmsDeliversFeedMessagesToObserver() throws Exception {
-        AlarmFeedMessage active = AlarmFeedMessage.newBuilder()
-                .setActiveAlarm(ActiveAlarmSnapshot.newBuilder()
-                        .setAlarmFullReference("Area1.Tank.Level.Hi")
-                        .setSeverity(800)
-                        .setCurrentState(AlarmConditionState.ALARM_CONDITION_STATE_ACTIVE))
-                .build();
-        AlarmFeedMessage snapshotComplete =
-                AlarmFeedMessage.newBuilder().setSnapshotComplete(true).build();
-        TestService service = new TestService() {
-            @Override
-            public void streamAlarms(
-                    StreamAlarmsRequest request, StreamObserver<AlarmFeedMessage> responseObserver) {
-                responseObserver.onNext(active);
-                responseObserver.onNext(snapshotComplete);
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            List<AlarmFeedMessage> received = new ArrayList<>();
-            CountDownLatch done = new CountDownLatch(1);
-            harness.client().streamAlarms(
-                    StreamAlarmsRequest.newBuilder().build(),
-                    new StreamObserver<>() {
-                        @Override
-                        public void onNext(AlarmFeedMessage value) {
-                            received.add(value);
-                        }
-
-                        @Override
-                        public void onError(Throwable t) {
-                            done.countDown();
-                        }
-
-                        @Override
-                        public void onCompleted() {
-                            done.countDown();
-                        }
-                    });
-            assertTrue(done.await(5, TimeUnit.SECONDS), "stream should complete");
-            assertEquals(2, received.size());
-            assertEquals("Area1.Tank.Level.Hi", received.get(0).getActiveAlarm().getAlarmFullReference());
-            assertTrue(received.get(1).getSnapshotComplete());
-        }
-    }
-
-    @Test
-    void alarmFeedSubscriptionCancelBeforeBeforeStartCancelsStream() {
-        MxGatewayAlarmFeedSubscription subscription = new MxGatewayAlarmFeedSubscription();
-        ClientResponseObserver<StreamAlarmsRequest, AlarmFeedMessage> observer =
-                subscription.wrap(new StreamObserver<>() {
-                    @Override
-                    public void onNext(AlarmFeedMessage value) {
-                    }
-
-                    @Override
-                    public void onError(Throwable t) {
-                    }
-
-                    @Override
-                    public void onCompleted() {
-                    }
-                });
-        RecordingAlarmFeedRequestStream requestStream = new RecordingAlarmFeedRequestStream();
-
-        subscription.cancel();
-        observer.beforeStart(requestStream);
-
-        assertTrue(requestStream.cancelled);
-        assertEquals("client cancelled alarm feed", requestStream.cancelMessage);
-    }
-
-    // --- Client.Java-007: async streamEvents + subscription cancellation ---
-
-    @Test
-    void streamEventsAsyncDeliversEventsToObserver() throws Exception {
-        MxEvent event = MxEvent.newBuilder().setWorkerSequence(7).build();
-        TestService service = new TestService() {
-            @Override
-            public void streamEvents(StreamEventsRequest request, StreamObserver<MxEvent> responseObserver) {
-                responseObserver.onNext(event);
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            List<MxEvent> received = new ArrayList<>();
-            CountDownLatch done = new CountDownLatch(1);
-            harness.client().streamEventsAsync(
-                    StreamEventsRequest.newBuilder().setSessionId("s-5").build(),
-                    new StreamObserver<>() {
-                        @Override
-                        public void onNext(MxEvent value) {
-                            received.add(value);
-                        }
-
-                        @Override
-                        public void onError(Throwable t) {
-                            done.countDown();
-                        }
-
-                        @Override
-                        public void onCompleted() {
-                            done.countDown();
-                        }
-                    });
-            assertTrue(done.await(5, TimeUnit.SECONDS), "stream should complete");
-            assertEquals(1, received.size());
-            assertEquals(7, received.get(0).getWorkerSequence());
-        }
-    }
-
-    @Test
-    void eventSubscriptionCancelBeforeBeforeStartCancelsStream() {
-        MxGatewayEventSubscription subscription = new MxGatewayEventSubscription();
-        ClientResponseObserver<StreamEventsRequest, MxEvent> observer =
-                subscription.wrap(new StreamObserver<>() {
-                    @Override
-                    public void onNext(MxEvent value) {
-                    }
-
-                    @Override
-                    public void onError(Throwable t) {
-                    }
-
-                    @Override
-                    public void onCompleted() {
-                    }
-                });
-        RecordingEventsRequestStream requestStream = new RecordingEventsRequestStream();
-
-        subscription.cancel();
-        observer.beforeStart(requestStream);
-
-        assertTrue(requestStream.cancelled);
-        assertEquals("client cancelled event stream", requestStream.cancelMessage);
-    }
-
-    // --- Client.Java-007 / Client.Java-011: MxEventStream queue overflow ---
-
-    @Test
-    void eventStreamQueueOverflowSurfacesExceptionFromNext() {
-        MxEventStream stream = new MxEventStream(2);
-        ClientResponseObserver<StreamEventsRequest, MxEvent> observer = stream.observer();
-        RecordingEventsRequestStream requestStream = new RecordingEventsRequestStream();
-        observer.beforeStart(requestStream);
-
-        // Push far more events than the capacity-2 buffer can hold without draining.
-        for (int i = 0; i < 16; i++) {
-            observer.onNext(MxEvent.newBuilder().setWorkerSequence(i).build());
-        }
-
-        // Overflow must cancel the gRPC call and surface as MxGatewayException.
-        assertTrue(requestStream.cancelled, "overflow should cancel the underlying call");
-        MxGatewayException error = assertThrows(MxGatewayException.class, () -> {
-            while (stream.hasNext()) {
-                stream.next();
-            }
-        });
-        assertTrue(error.getMessage().contains("overflow"), error::getMessage);
-    }
-
-    // --- Client.Java-007: TLS channel construction ---
-
-    @Test
-    void connectWithMissingCaCertificateThrowsTypedTlsException() {
-        MxGatewayClientOptions options = MxGatewayClientOptions.builder()
-                .endpoint("localhost:5001")
-                .apiKey("mxgw_id_secret")
-                .plaintext(false)
-                .caCertificatePath(Path.of("does-not-exist-" + UUID.randomUUID() + ".pem"))
-                .build();
-
-        MxGatewayException error = assertThrows(MxGatewayException.class, () -> MxGatewayClient.connect(options));
-        assertTrue(error.getMessage().contains("TLS"), error::getMessage);
-
-        MxGatewayException galaxyError =
-                assertThrows(MxGatewayException.class, () -> GalaxyRepositoryClient.connect(options));
-        assertTrue(galaxyError.getMessage().contains("TLS"), galaxyError::getMessage);
-    }
-
-    @Test
-    void connectWithSystemTrustBuildsTlsChannelWithoutError() {
-        // No CA path and plaintext=false exercises the useTransportSecurity() branch.
-        MxGatewayClientOptions options = MxGatewayClientOptions.builder()
-                .endpoint("localhost:5001")
-                .apiKey("mxgw_id_secret")
-                .plaintext(false)
-                .build();
-
-        try (MxGatewayClient client = MxGatewayClient.connect(options)) {
-            assertNotNull(client);
-        }
-        try (GalaxyRepositoryClient galaxy = GalaxyRepositoryClient.connect(options)) {
-            assertNotNull(galaxy);
-        }
-    }
-
-    // --- Client.Java-008: async error surface is normalised ---
-
-    @Test
-    void openSessionAsyncNormalisesNonGatewayRuntimeExceptionFromValidator() {
-        // ensureGatewayProtocolCompatible already throws MxGatewayException; this verifies
-        // the normalisingValidator wrapper routes a stray RuntimeException through fromGrpc.
-        CompletableFuture<String> source = new CompletableFuture<>();
-        CompletableFuture<String> wrapped =
-                source.thenApply(MxGatewayChannels.normalisingValidator("open session", reply -> {
-                    throw new IllegalStateException("malformed reply");
-                }));
-        source.complete("payload");
-
-        CompletionException error = assertThrows(CompletionException.class, wrapped::join);
-        assertTrue(error.getCause() instanceof MxGatewayException, () -> String.valueOf(error.getCause()));
-    }
-
-    private static ProtocolStatus ok() {
-        return ProtocolStatus.newBuilder()
-                .setCode(ProtocolStatusCode.PROTOCOL_STATUS_CODE_OK)
-                .build();
-    }
-
-    private static class TestService extends MxAccessGatewayGrpc.MxAccessGatewayImplBase {
-    }
-
-    private record Harness(Server server, ManagedChannel channel, MxGatewayClient client) implements AutoCloseable {
-        static Harness start(MxAccessGatewayGrpc.MxAccessGatewayImplBase service) throws Exception {
-            return start(service, "", new AtomicReference<>());
-        }
-
-        static Harness start(
-                MxAccessGatewayGrpc.MxAccessGatewayImplBase service,
-                String apiKey,
-                AtomicReference<String> authorization)
-                throws Exception {
-            String name = "mxgw-low-" + UUID.randomUUID();
-            io.grpc.ServerInterceptor interceptor = new io.grpc.ServerInterceptor() {
-                @Override
-                public <ReqT, RespT> io.grpc.ServerCall.Listener<ReqT> interceptCall(
-                        io.grpc.ServerCall<ReqT, RespT> call,
-                        io.grpc.Metadata headers,
-                        io.grpc.ServerCallHandler<ReqT, RespT> next) {
-                    authorization.set(headers.get(MxGatewayAuthInterceptor.AUTHORIZATION_HEADER));
-                    return next.startCall(call, headers);
-                }
-            };
-            Server server = InProcessServerBuilder.forName(name)
-                    .directExecutor()
-                    .addService(io.grpc.ServerInterceptors.intercept(service, interceptor))
-                    .build()
-                    .start();
-            ManagedChannel channel = InProcessChannelBuilder.forName(name).directExecutor().build();
-            MxGatewayClient client = new MxGatewayClient(
-                    channel,
-                    MxGatewayClientOptions.builder()
-                            .endpoint("in-process")
-                            .apiKey(apiKey)
-                            .plaintext(true)
-                            .callTimeout(Duration.ofSeconds(5))
-                            .streamTimeout(Duration.ofSeconds(5))
-                            .build());
-            return new Harness(server, channel, client);
-        }
-
-        @Override
-        public void close() {
-            channel.shutdownNow();
-            server.shutdownNow();
-        }
-    }
-
-    private static final class RecordingEventsRequestStream
-            extends ClientCallStreamObserver<StreamEventsRequest> {
-        private boolean cancelled;
-        private String cancelMessage;
-
-        @Override
-        public void cancel(String message, Throwable cause) {
-            cancelled = true;
-            cancelMessage = message;
-        }
-
-        @Override
-        public boolean isReady() {
-            return true;
-        }
-
-        @Override
-        public void setOnReadyHandler(Runnable onReadyHandler) {
-        }
-
-        @Override
-        public void request(int count) {
-        }
-
-        @Override
-        public void setMessageCompression(boolean enable) {
-        }
-
-        @Override
-        public void disableAutoInboundFlowControl() {
-        }
-
-        @Override
-        public void onNext(StreamEventsRequest value) {
-        }
-
-        @Override
-        public void onError(Throwable t) {
-        }
-
-        @Override
-        public void onCompleted() {
-        }
-    }
-
-    private static final class RecordingAlarmFeedRequestStream
-            extends ClientCallStreamObserver<StreamAlarmsRequest> {
-        private boolean cancelled;
-        private String cancelMessage;
-
-        @Override
-        public void cancel(String message, Throwable cause) {
-            cancelled = true;
-            cancelMessage = message;
-        }
-
-        @Override
-        public boolean isReady() {
-            return true;
-        }
-
-        @Override
-        public void setOnReadyHandler(Runnable onReadyHandler) {
-        }
-
-        @Override
-        public void request(int count) {
-        }
-
-        @Override
-        public void setMessageCompression(boolean enable) {
-        }
-
-        @Override
-        public void disableAutoInboundFlowControl() {
-        }
-
-        @Override
-        public void onNext(StreamAlarmsRequest value) {
-        }
-
-        @Override
-        public void onError(Throwable t) {
-        }
-
-        @Override
-        public void onCompleted() {
-        }
-    }
-}
@@ -1,527 +0,0 @@
-package com.dohertylan.mxgateway.client;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import io.grpc.ManagedChannel;
-import io.grpc.Server;
-import io.grpc.inprocess.InProcessChannelBuilder;
-import io.grpc.inprocess.InProcessServerBuilder;
-import io.grpc.stub.StreamObserver;
-import java.time.Duration;
-import java.util.UUID;
-import java.util.concurrent.CompletableFuture;
-import mxaccess_gateway.v1.MxAccessGatewayGrpc;
-import mxaccess_gateway.v1.MxaccessGateway.CloseSessionReply;
-import mxaccess_gateway.v1.MxaccessGateway.CloseSessionRequest;
-import mxaccess_gateway.v1.MxaccessGateway.MxCommandKind;
-import mxaccess_gateway.v1.MxaccessGateway.MxCommandReply;
-import mxaccess_gateway.v1.MxaccessGateway.MxCommandRequest;
-import mxaccess_gateway.v1.MxaccessGateway.OpenSessionReply;
-import mxaccess_gateway.v1.MxaccessGateway.OpenSessionRequest;
-import mxaccess_gateway.v1.MxaccessGateway.ProtocolStatus;
-import mxaccess_gateway.v1.MxaccessGateway.ProtocolStatusCode;
-import org.junit.jupiter.api.Test;
-
-/**
- * Regression tests for the Medium-severity Client.Java code-review findings
- * (Client.Java-001 through Client.Java-005, and Client.Java-014/015).
- */
-final class MxGatewayMediumFindingsTests {
-
-    // --- Client.Java-001: redactApiKey must not leak trailing secret chars ---
-
-    @Test
-    void redactApiKeyDoesNotLeakAnyCharacterOfTheSecret() {
-        // mxgw_<key-id>_<secret> — the secret is the segment after the second underscore.
-        String apiKey = "mxgw_keyid01_supersecretvalue";
-        String redacted = MxGatewaySecrets.redactApiKey(apiKey);
-
-        // None of the secret characters may appear in the redacted output.
-        assertFalse(redacted.contains("value"), () -> "redacted form leaked secret tail: " + redacted);
-        assertFalse(redacted.endsWith("alue"), () -> "redacted form leaked trailing secret chars: " + redacted);
-        assertFalse(redacted.contains("supersecret"), () -> "redacted form leaked secret: " + redacted);
-        // The non-secret key-id prefix may stay so the value is still comparable in logs.
-        assertTrue(redacted.startsWith("mxgw_keyid01_"), () -> "redacted form lost key-id prefix: " + redacted);
-    }
-
-    @Test
-    void redactApiKeyForNonGatewayShapedKeyRevealsNothing() {
-        String redacted = MxGatewaySecrets.redactApiKey("plain-opaque-token-1234");
-        assertFalse(redacted.contains("1234"), () -> "redacted form leaked trailing chars: " + redacted);
-        assertFalse(redacted.contains("plain-opaque-token"), () -> "redacted form leaked body: " + redacted);
-    }
-
-    @Test
-    void redactApiKeyStillHandlesNullAndShortInput() {
-        assertEquals("", MxGatewaySecrets.redactApiKey(null));
-        assertEquals("", MxGatewaySecrets.redactApiKey(""));
-        assertEquals("<redacted>", MxGatewaySecrets.redactApiKey("short"));
-    }
-
-    // --- Client.Java-002: terminal-state transition must be deterministic ---
-
-    @Test
-    void eventStreamOverflowExceptionSurvivesASubsequentClose() {
-        // Deterministic reproduction of Client.Java-002: an overflow enqueues the
-        // overflow exception, then a later close() must NOT discard it. The first
-        // terminal condition (overflow) must win and stay observable by next().
-        MxEventStream stream = new MxEventStream(2);
-        io.grpc.stub.ClientResponseObserver<
-                        mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest,
-                        mxaccess_gateway.v1.MxaccessGateway.MxEvent>
-                observer = stream.observer();
-        observer.beforeStart(new NoopRequestStream());
-
-        // Force a queue overflow on a capacity-2 stream.
-        for (int i = 0; i < 8; i++) {
-            observer.onNext(testEvent(i));
-        }
-
-        // A close() arriving after the overflow must not erase the overflow signal.
-        stream.close();
-
-        MxGatewayException error = assertThrows(MxGatewayException.class, () -> {
-            while (stream.hasNext()) {
-                stream.next();
-            }
-        });
-        assertTrue(error.getMessage().contains("overflow"), error::getMessage);
-    }
-
-    @Test
-    void eventStreamConcurrentOverflowAndCloseAlwaysTerminate() throws Exception {
-        // The terminal-state transition must be serialised: whatever the interleaving
-        // of overflow and close, hasNext() always reaches a terminal state.
-        for (int iteration = 0; iteration < 300; iteration++) {
-            MxEventStream stream = new MxEventStream(2);
-            io.grpc.stub.ClientResponseObserver<
-                            mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest,
-                            mxaccess_gateway.v1.MxaccessGateway.MxEvent>
-                    observer = stream.observer();
-            observer.beforeStart(new NoopRequestStream());
-
-            Thread filler = new Thread(() -> {
-                for (int i = 0; i < 8; i++) {
-                    observer.onNext(testEvent(i));
-                }
-            });
-            Thread closer = new Thread(stream::close);
-            filler.start();
-            closer.start();
-            filler.join();
-            closer.join();
-
-            try {
-                while (stream.hasNext()) {
-                    stream.next();
-                }
-            } catch (MxGatewayException expected) {
-                assertTrue(expected.getMessage().contains("overflow"), expected::getMessage);
-            }
-            assertFalse(stream.hasNext());
-        }
-    }
-
-    private static final class NoopRequestStream
-            extends io.grpc.stub.ClientCallStreamObserver<mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest> {
-        @Override
-        public void cancel(String message, Throwable cause) {
-        }
-
-        @Override
-        public boolean isReady() {
-            return true;
-        }
-
-        @Override
-        public void setOnReadyHandler(Runnable onReadyHandler) {
-        }
-
-        @Override
-        public void request(int count) {
-        }
-
-        @Override
-        public void setMessageCompression(boolean enable) {
-        }
-
-        @Override
-        public void disableAutoInboundFlowControl() {
-        }
-
-        @Override
-        public void onNext(mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest value) {
-        }
-
-        @Override
-        public void onError(Throwable t) {
-        }
-
-        @Override
-        public void onCompleted() {
-        }
-    }
-
-    // --- Client.Java-003: gateway protocol version mismatch must be rejected ---
-
-    @Test
-    void openSessionRejectsIncompatibleGatewayProtocolVersion() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void openSession(OpenSessionRequest request, StreamObserver<OpenSessionReply> responseObserver) {
-                responseObserver.onNext(OpenSessionReply.newBuilder()
-                        .setSessionId("session-mismatch")
-                        .setGatewayProtocolVersion(MxGatewayClientVersion.gatewayProtocolVersion() + 1)
-                        .setProtocolStatus(ok())
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            MxGatewayException error = assertThrows(
-                    MxGatewayException.class,
-                    () -> harness.client().openSession("junit-session"));
-            assertTrue(error.getMessage().contains("protocol version"), error::getMessage);
-        }
-    }
-
-    @Test
-    void openSessionAcceptsMatchingOrUnsetGatewayProtocolVersion() throws Exception {
-        TestService matching = new TestService() {
-            @Override
-            public void openSession(OpenSessionRequest request, StreamObserver<OpenSessionReply> responseObserver) {
-                responseObserver.onNext(OpenSessionReply.newBuilder()
-                        .setSessionId("session-ok")
-                        .setGatewayProtocolVersion(MxGatewayClientVersion.gatewayProtocolVersion())
-                        .setProtocolStatus(ok())
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-        try (Harness harness = Harness.start(matching)) {
-            assertEquals("session-ok", harness.client().openSession("junit-session").sessionId());
-        }
-
-        // A gateway that leaves the field unset (0) must not be rejected — older gateways
-        // simply do not populate it.
-        TestService unset = new TestService();
-        try (Harness harness = Harness.start(unset)) {
-            assertEquals("session-java", harness.client().openSession("junit-session").sessionId());
-        }
-    }
-
-    // --- Client.Java-004: missing typed payload AND missing return_value must throw ---
-
-    @Test
-    void registerThrowsWhenReplyHasNeitherTypedPayloadNorReturnValue() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void invoke(MxCommandRequest request, StreamObserver<MxCommandReply> responseObserver) {
-                // Reply with neither register payload nor return_value set.
-                responseObserver.onNext(MxCommandReply.newBuilder()
-                        .setSessionId(request.getSessionId())
-                        .setKind(request.getCommand().getKind())
-                        .setProtocolStatus(ok())
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            MxGatewaySession session = MxGatewaySession.forSessionId(harness.client(), "s");
-            MxGatewayException error = assertThrows(
-                    MxGatewayException.class, () -> session.register("c"));
-            assertTrue(error.getMessage().contains("register"), error::getMessage);
-        }
-    }
-
-    @Test
-    void addItemThrowsWhenReplyHasNeitherTypedPayloadNorReturnValue() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void invoke(MxCommandRequest request, StreamObserver<MxCommandReply> responseObserver) {
-                responseObserver.onNext(MxCommandReply.newBuilder()
-                        .setSessionId(request.getSessionId())
-                        .setKind(request.getCommand().getKind())
-                        .setProtocolStatus(ok())
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            MxGatewaySession session = MxGatewaySession.forSessionId(harness.client(), "s");
-            assertThrows(MxGatewayException.class, () -> session.addItem(1, "Tag"));
-            assertThrows(MxGatewayException.class, () -> session.addItem2(1, "Tag", "ctx"));
-        }
-    }
-
-    @Test
-    void addItemStillHonoursReturnValueFallback() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void invoke(MxCommandRequest request, StreamObserver<MxCommandReply> responseObserver) {
-                responseObserver.onNext(MxCommandReply.newBuilder()
-                        .setSessionId(request.getSessionId())
-                        .setKind(request.getCommand().getKind())
-                        .setProtocolStatus(ok())
-                        .setReturnValue(mxaccess_gateway.v1.MxaccessGateway.MxValue.newBuilder()
-                                .setInt32Value(99))
-                        .build());
-                responseObserver.onCompleted();
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            MxGatewaySession session = MxGatewaySession.forSessionId(harness.client(), "s");
-            assertEquals(99, session.addItem(1, "Tag"));
-        }
-    }
-
-    // --- Client.Java-005: close() must not mask the primary try-with-resources error ---
-
-    @Test
-    void closeSuppressesCloseTimeFailureInsteadOfMaskingBodyException() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void closeSession(CloseSessionRequest request, StreamObserver<CloseSessionReply> responseObserver) {
-                responseObserver.onError(io.grpc.Status.UNAVAILABLE
-                        .withDescription("WORKER_UNAVAILABLE")
-                        .asRuntimeException());
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            IllegalStateException bodyError = assertThrows(IllegalStateException.class, () -> {
-                try (MxGatewaySession session = MxGatewaySession.forSessionId(harness.client(), "s")) {
-                    throw new IllegalStateException("body failure");
-                }
-            });
-            // The body exception must propagate; the close-time RPC failure must not replace it.
-            assertEquals("body failure", bodyError.getMessage());
-        }
-    }
-
-    @Test
-    void closeRawStillSurfacesCloseTimeFailureForCallersWhoWantIt() throws Exception {
-        TestService service = new TestService() {
-            @Override
-            public void closeSession(CloseSessionRequest request, StreamObserver<CloseSessionReply> responseObserver) {
-                responseObserver.onError(io.grpc.Status.UNAVAILABLE
-                        .withDescription("WORKER_UNAVAILABLE")
-                        .asRuntimeException());
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            MxGatewaySession session = MxGatewaySession.forSessionId(harness.client(), "s");
-            assertThrows(MxGatewayException.class, session::closeRaw);
-        }
-    }
-
-    // --- Client.Java-014: MxEventStream.close() before beforeStart must cancel the call ---
-
-    @Test
-    void mxEventStreamCloseBeforeBeforeStartCancelsStream() {
-        // Mirrors GalaxyRepositoryClientTests.deployEventStreamCloseBeforeBeforeStartCancelsStream:
-        // if close() runs before the gRPC call has attached its ClientCallStreamObserver,
-        // beforeStart() must observe the prior close and cancel the underlying call so the
-        // gRPC subscription does not leak open after the consumer has stopped iterating.
-        MxEventStream stream = new MxEventStream(4);
-        io.grpc.stub.ClientResponseObserver<
-                        mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest,
-                        mxaccess_gateway.v1.MxaccessGateway.MxEvent>
-                observer = stream.observer();
-        RecordingEventsRequestStream requestStream = new RecordingEventsRequestStream();
-
-        stream.close();
-        observer.beforeStart(requestStream);
-
-        assertTrue(requestStream.cancelled, "beforeStart must cancel the underlying call after a prior close()");
-        assertEquals("client cancelled event stream", requestStream.cancelMessage);
-        assertFalse(stream.hasNext());
-    }
-
-    // --- Client.Java-015: cancelling the user-visible *Async future cancels the gRPC call ---
-
-    @Test
-    void invokeAsyncCancellationCancelsUnderlyingGrpcCall() throws Exception {
-        // Set up a gateway service that never completes the invoke call so cancellation is
-        // the only way the call terminates. Hook ServerCallStreamObserver.setOnCancelHandler
-        // to latch when the server observes cancellation.
-        java.util.concurrent.CountDownLatch serverCancelled = new java.util.concurrent.CountDownLatch(1);
-        TestService service = new TestService() {
-            @Override
-            public void invoke(MxCommandRequest request, StreamObserver<MxCommandReply> responseObserver) {
-                io.grpc.stub.ServerCallStreamObserver<MxCommandReply> serverObserver =
-                        (io.grpc.stub.ServerCallStreamObserver<MxCommandReply>) responseObserver;
-                serverObserver.setOnCancelHandler(serverCancelled::countDown);
-                // Intentionally never complete — the call must be terminated by the client
-                // cancelling its future, which must propagate to the gRPC cancellation.
-            }
-        };
-
-        try (Harness harness = Harness.start(service)) {
-            CompletableFuture<MxCommandReply> future = harness.client().invokeAsync(MxCommandRequest.newBuilder()
-                    .setSessionId("s-cancel")
-                    .setCommand(mxaccess_gateway.v1.MxaccessGateway.MxCommand.newBuilder()
-                            .setKind(MxCommandKind.MX_COMMAND_KIND_REGISTER))
-                    .build());
-
-            // Cancellation of the user-visible future must propagate to the gRPC call.
-            assertTrue(future.cancel(true), "cancel(true) should return true on a pending future");
-            assertTrue(
-                    serverCancelled.await(5, java.util.concurrent.TimeUnit.SECONDS),
-                    "server must observe RPC cancellation after future.cancel(true)");
-        }
-    }
-
-    @Test
-    void toCompletableValidatorOverloadForwardsCancellationToSource() {
-        // Unit-level proof: cancel() on the future returned by the validator-aware
-        // toCompletable overload must call cancel(true) on the source ListenableFuture.
-        // This is the core fix for Client.Java-015 — the validator runs inside
-        // toCompletable instead of via .thenApply, so the user holds the future
-        // that is bound to the source.
-        com.google.common.util.concurrent.SettableFuture<String> source =
-                com.google.common.util.concurrent.SettableFuture.create();
-        java.util.concurrent.CompletableFuture<Integer> target =
-                MxGatewayChannels.toCompletable(source, "noop", String::length);
-
-        assertFalse(source.isCancelled());
-        assertTrue(target.cancel(true));
-        assertTrue(source.isCancelled(), "source ListenableFuture must be cancelled");
-    }
-
-    @Test
-    void toCompletableNoValidatorOverloadForwardsCancellationToSource() {
-        // Regression for the no-validator overload (the historic toCompletable shape).
-        com.google.common.util.concurrent.SettableFuture<String> source =
-                com.google.common.util.concurrent.SettableFuture.create();
-        java.util.concurrent.CompletableFuture<String> target = MxGatewayChannels.toCompletable(source, "noop");
-
-        assertFalse(source.isCancelled());
-        assertTrue(target.cancel(true));
-        assertTrue(source.isCancelled(), "source ListenableFuture must be cancelled");
-    }
-
-    private static final class RecordingEventsRequestStream
-            extends io.grpc.stub.ClientCallStreamObserver<
-                    mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest> {
-        private boolean cancelled;
-        private String cancelMessage;
-
-        @Override
-        public void cancel(String message, Throwable cause) {
-            cancelled = true;
-            cancelMessage = message;
-        }
-
-        @Override
-        public boolean isReady() {
-            return true;
-        }
-
-        @Override
-        public void setOnReadyHandler(Runnable onReadyHandler) {
-        }
-
-        @Override
-        public void request(int count) {
-        }
-
-        @Override
-        public void setMessageCompression(boolean enable) {
-        }
-
-        @Override
-        public void disableAutoInboundFlowControl() {
-        }
-
-        @Override
-        public void onNext(mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest value) {
-        }
-
-        @Override
-        public void onError(Throwable t) {
-        }
-
-        @Override
-        public void onCompleted() {
-        }
-    }
-
-    private static mxaccess_gateway.v1.MxaccessGateway.MxEvent testEvent(int sequence) {
-        return mxaccess_gateway.v1.MxaccessGateway.MxEvent.newBuilder()
-                .setWorkerSequence(sequence)
-                .build();
-    }
-
-    private static ProtocolStatus ok() {
-        return ProtocolStatus.newBuilder()
-                .setCode(ProtocolStatusCode.PROTOCOL_STATUS_CODE_OK)
-                .build();
-    }
-
-    private static class TestService extends MxAccessGatewayGrpc.MxAccessGatewayImplBase {
-        @Override
-        public void openSession(OpenSessionRequest request, StreamObserver<OpenSessionReply> responseObserver) {
-            responseObserver.onNext(OpenSessionReply.newBuilder()
-                    .setSessionId("session-java")
-                    .setProtocolStatus(ok())
-                    .build());
-            responseObserver.onCompleted();
-        }
-
-        @Override
-        public void closeSession(CloseSessionRequest request, StreamObserver<CloseSessionReply> responseObserver) {
-            responseObserver.onNext(CloseSessionReply.newBuilder()
-                    .setSessionId(request.getSessionId())
-                    .setProtocolStatus(ok())
-                    .build());
-            responseObserver.onCompleted();
-        }
-
-        @Override
-        public void invoke(MxCommandRequest request, StreamObserver<MxCommandReply> responseObserver) {
-            responseObserver.onNext(MxCommandReply.newBuilder()
-                    .setSessionId(request.getSessionId())
-                    .setKind(MxCommandKind.MX_COMMAND_KIND_UNSPECIFIED)
-                    .setProtocolStatus(ok())
-                    .build());
-            responseObserver.onCompleted();
-        }
-    }
-
-    private record Harness(Server server, ManagedChannel channel, MxGatewayClient client) implements AutoCloseable {
-        static Harness start(MxAccessGatewayGrpc.MxAccessGatewayImplBase service) throws Exception {
-            String name = "mxgw-medium-" + UUID.randomUUID();
-            Server server = InProcessServerBuilder.forName(name)
-                    .directExecutor()
-                    .addService(service)
-                    .build()
-                    .start();
-            ManagedChannel channel = InProcessChannelBuilder.forName(name).directExecutor().build();
-            MxGatewayClient client = new MxGatewayClient(
-                    channel,
-                    MxGatewayClientOptions.builder()
-                            .endpoint("in-process")
-                            .apiKey("")
-                            .plaintext(true)
-                            .callTimeout(Duration.ofSeconds(5))
-                            .build());
-            return new Harness(server, channel, client);
-        }
-
-        @Override
-        public void close() {
-            channel.shutdownNow();
-            server.shutdownNow();
-        }
-    }
-}
@@ -9,6 +9,10 @@ pluginManagement {
    }
 }

+plugins {
+    id 'org.gradle.toolchains.foojay-resolver-convention' version '1.0.0'
+}
+
 dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
@@ -16,7 +20,7 @@ dependencyResolutionManagement {
    }
 }

-rootProject.name = 'mxaccessgw-java'
+rootProject.name = 'zb-mom-ww-mxaccessgw-java'

-include 'mxgateway-client'
-include 'mxgateway-cli'
+include 'zb-mom-ww-mxgateway-client'
+include 'zb-mom-ww-mxgateway-cli'
@@ -142,6 +142,37 @@ public final class GalaxyRepositoryGrpc {
    return getWatchDeployEventsMethod;
  }

+  private static volatile io.grpc.MethodDescriptor<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest,
+      galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> getBrowseChildrenMethod;
+
+  @io.grpc.stub.annotations.RpcMethod(
+      fullMethodName = SERVICE_NAME + '/' + "BrowseChildren",
+      requestType = galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest.class,
+      responseType = galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply.class,
+      methodType = io.grpc.MethodDescriptor.MethodType.UNARY)
+  public static io.grpc.MethodDescriptor<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest,
+      galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> getBrowseChildrenMethod() {
+    io.grpc.MethodDescriptor<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest, galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> getBrowseChildrenMethod;
+    if ((getBrowseChildrenMethod = GalaxyRepositoryGrpc.getBrowseChildrenMethod) == null) {
+      synchronized (GalaxyRepositoryGrpc.class) {
+        if ((getBrowseChildrenMethod = GalaxyRepositoryGrpc.getBrowseChildrenMethod) == null) {
+          GalaxyRepositoryGrpc.getBrowseChildrenMethod = getBrowseChildrenMethod =
+              io.grpc.MethodDescriptor.<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest, galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply>newBuilder()
+              .setType(io.grpc.MethodDescriptor.MethodType.UNARY)
+              .setFullMethodName(generateFullMethodName(SERVICE_NAME, "BrowseChildren"))
+              .setSampledToLocalTracing(true)
+              .setRequestMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
+                  galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest.getDefaultInstance()))
+              .setResponseMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
+                  galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply.getDefaultInstance()))
+              .setSchemaDescriptor(new GalaxyRepositoryMethodDescriptorSupplier("BrowseChildren"))
+              .build();
+        }
+      }
+    }
+    return getBrowseChildrenMethod;
+  }
+
  /**
   * Creates a new async stub that supports all call types for the service
   */
@@ -246,6 +277,19 @@ public final class GalaxyRepositoryGrpc {
        io.grpc.stub.StreamObserver<galaxy_repository.v1.GalaxyRepositoryOuterClass.DeployEvent> responseObserver) {
      io.grpc.stub.ServerCalls.asyncUnimplementedUnaryCall(getWatchDeployEventsMethod(), responseObserver);
    }
+
+    /**
+     * <pre>
+     * Returns the direct children of a parent object (or the root objects when
+     * `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+     * one level at a time instead of paging the full hierarchy. Filters mirror
+     * DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+     * </pre>
+     */
+    default void browseChildren(galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest request,
+        io.grpc.stub.StreamObserver<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> responseObserver) {
+      io.grpc.stub.ServerCalls.asyncUnimplementedUnaryCall(getBrowseChildrenMethod(), responseObserver);
+    }
  }

  /**
@@ -326,6 +370,20 @@ public final class GalaxyRepositoryGrpc {
      io.grpc.stub.ClientCalls.asyncServerStreamingCall(
          getChannel().newCall(getWatchDeployEventsMethod(), getCallOptions()), request, responseObserver);
    }
+
+    /**
+     * <pre>
+     * Returns the direct children of a parent object (or the root objects when
+     * `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+     * one level at a time instead of paging the full hierarchy. Filters mirror
+     * DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+     * </pre>
+     */
+    public void browseChildren(galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest request,
+        io.grpc.stub.StreamObserver<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> responseObserver) {
+      io.grpc.stub.ClientCalls.asyncUnaryCall(
+          getChannel().newCall(getBrowseChildrenMethod(), getCallOptions()), request, responseObserver);
+    }
  }

  /**
@@ -387,6 +445,19 @@ public final class GalaxyRepositoryGrpc {
      return io.grpc.stub.ClientCalls.blockingV2ServerStreamingCall(
          getChannel(), getWatchDeployEventsMethod(), getCallOptions(), request);
    }
+
+    /**
+     * <pre>
+     * Returns the direct children of a parent object (or the root objects when
+     * `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+     * one level at a time instead of paging the full hierarchy. Filters mirror
+     * DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+     * </pre>
+     */
+    public galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply browseChildren(galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest request) throws io.grpc.StatusException {
+      return io.grpc.stub.ClientCalls.blockingV2UnaryCall(
+          getChannel(), getBrowseChildrenMethod(), getCallOptions(), request);
+    }
  }

  /**
@@ -447,6 +518,19 @@ public final class GalaxyRepositoryGrpc {
      return io.grpc.stub.ClientCalls.blockingServerStreamingCall(
          getChannel(), getWatchDeployEventsMethod(), getCallOptions(), request);
    }
+
+    /**
+     * <pre>
+     * Returns the direct children of a parent object (or the root objects when
+     * `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+     * one level at a time instead of paging the full hierarchy. Filters mirror
+     * DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+     * </pre>
+     */
+    public galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply browseChildren(galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest request) {
+      return io.grpc.stub.ClientCalls.blockingUnaryCall(
+          getChannel(), getBrowseChildrenMethod(), getCallOptions(), request);
+    }
  }

  /**
@@ -494,12 +578,27 @@ public final class GalaxyRepositoryGrpc {
      return io.grpc.stub.ClientCalls.futureUnaryCall(
          getChannel().newCall(getDiscoverHierarchyMethod(), getCallOptions()), request);
    }
+
+    /**
+     * <pre>
+     * Returns the direct children of a parent object (or the root objects when
+     * `parent` is unset). Designed for OPC UA-style lazy expand: clients walk
+     * one level at a time instead of paging the full hierarchy. Filters mirror
+     * DiscoverHierarchy exactly. Backed by the same shared hierarchy cache.
+     * </pre>
+     */
+    public com.google.common.util.concurrent.ListenableFuture<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply> browseChildren(
+        galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest request) {
+      return io.grpc.stub.ClientCalls.futureUnaryCall(
+          getChannel().newCall(getBrowseChildrenMethod(), getCallOptions()), request);
+    }
  }

  private static final int METHODID_TEST_CONNECTION = 0;
  private static final int METHODID_GET_LAST_DEPLOY_TIME = 1;
  private static final int METHODID_DISCOVER_HIERARCHY = 2;
  private static final int METHODID_WATCH_DEPLOY_EVENTS = 3;
+  private static final int METHODID_BROWSE_CHILDREN = 4;

  private static final class MethodHandlers<Req, Resp> implements
      io.grpc.stub.ServerCalls.UnaryMethod<Req, Resp>,
@@ -534,6 +633,10 @@ public final class GalaxyRepositoryGrpc {
          serviceImpl.watchDeployEvents((galaxy_repository.v1.GalaxyRepositoryOuterClass.WatchDeployEventsRequest) request,
              (io.grpc.stub.StreamObserver<galaxy_repository.v1.GalaxyRepositoryOuterClass.DeployEvent>) responseObserver);
          break;
+        case METHODID_BROWSE_CHILDREN:
+          serviceImpl.browseChildren((galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest) request,
+              (io.grpc.stub.StreamObserver<galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply>) responseObserver);
+          break;
        default:
          throw new AssertionError();
      }
@@ -580,6 +683,13 @@ public final class GalaxyRepositoryGrpc {
              galaxy_repository.v1.GalaxyRepositoryOuterClass.WatchDeployEventsRequest,
              galaxy_repository.v1.GalaxyRepositoryOuterClass.DeployEvent>(
                service, METHODID_WATCH_DEPLOY_EVENTS)))
+        .addMethod(
+          getBrowseChildrenMethod(),
+          io.grpc.stub.ServerCalls.asyncUnaryCall(
+            new MethodHandlers<
+              galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest,
+              galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply>(
+                service, METHODID_BROWSE_CHILDREN)))
        .build();
  }

@@ -632,6 +742,7 @@ public final class GalaxyRepositoryGrpc {
              .addMethod(getGetLastDeployTimeMethod())
              .addMethod(getDiscoverHierarchyMethod())
              .addMethod(getWatchDeployEventsMethod())
+              .addMethod(getBrowseChildrenMethod())
              .build();
        }
      }
@@ -201,6 +201,37 @@ public final class MxAccessGatewayGrpc {
    return getStreamAlarmsMethod;
  }

+  private static volatile io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest,
+      mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> getQueryActiveAlarmsMethod;
+
+  @io.grpc.stub.annotations.RpcMethod(
+      fullMethodName = SERVICE_NAME + '/' + "QueryActiveAlarms",
+      requestType = mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest.class,
+      responseType = mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot.class,
+      methodType = io.grpc.MethodDescriptor.MethodType.SERVER_STREAMING)
+  public static io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest,
+      mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> getQueryActiveAlarmsMethod() {
+    io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest, mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> getQueryActiveAlarmsMethod;
+    if ((getQueryActiveAlarmsMethod = MxAccessGatewayGrpc.getQueryActiveAlarmsMethod) == null) {
+      synchronized (MxAccessGatewayGrpc.class) {
+        if ((getQueryActiveAlarmsMethod = MxAccessGatewayGrpc.getQueryActiveAlarmsMethod) == null) {
+          MxAccessGatewayGrpc.getQueryActiveAlarmsMethod = getQueryActiveAlarmsMethod =
+              io.grpc.MethodDescriptor.<mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest, mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot>newBuilder()
+              .setType(io.grpc.MethodDescriptor.MethodType.SERVER_STREAMING)
+              .setFullMethodName(generateFullMethodName(SERVICE_NAME, "QueryActiveAlarms"))
+              .setSampledToLocalTracing(true)
+              .setRequestMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
+                  mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest.getDefaultInstance()))
+              .setResponseMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
+                  mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot.getDefaultInstance()))
+              .setSchemaDescriptor(new MxAccessGatewayMethodDescriptorSupplier("QueryActiveAlarms"))
+              .build();
+        }
+      }
+    }
+    return getQueryActiveAlarmsMethod;
+  }
+
  /**
   * Creates a new async stub that supports all call types for the service
   */
@@ -315,6 +346,23 @@ public final class MxAccessGatewayGrpc {
        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> responseObserver) {
      io.grpc.stub.ServerCalls.asyncUnimplementedUnaryCall(getStreamAlarmsMethod(), responseObserver);
    }
+
+    /**
+     * <pre>
+     * Point-in-time snapshot of the currently-active alarm set served from the
+     * gateway's always-on alarm monitor cache (session-less). Used after a
+     * reconnect to seed Part 9 client state, or to reconcile alarms that may
+     * have been missed during a transport blip. Streamed so callers can
+     * begin processing without buffering the full set.
+     * `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+     * snapshot to alarms whose `alarm_full_reference` starts with the given
+     * prefix; an empty prefix returns the full set.
+     * </pre>
+     */
+    default void queryActiveAlarms(mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request,
+        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> responseObserver) {
+      io.grpc.stub.ServerCalls.asyncUnimplementedUnaryCall(getQueryActiveAlarmsMethod(), responseObserver);
+    }
  }

  /**
@@ -404,6 +452,24 @@ public final class MxAccessGatewayGrpc {
      io.grpc.stub.ClientCalls.asyncServerStreamingCall(
          getChannel().newCall(getStreamAlarmsMethod(), getCallOptions()), request, responseObserver);
    }
+
+    /**
+     * <pre>
+     * Point-in-time snapshot of the currently-active alarm set served from the
+     * gateway's always-on alarm monitor cache (session-less). Used after a
+     * reconnect to seed Part 9 client state, or to reconcile alarms that may
+     * have been missed during a transport blip. Streamed so callers can
+     * begin processing without buffering the full set.
+     * `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+     * snapshot to alarms whose `alarm_full_reference` starts with the given
+     * prefix; an empty prefix returns the full set.
+     * </pre>
+     */
+    public void queryActiveAlarms(mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request,
+        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> responseObserver) {
+      io.grpc.stub.ClientCalls.asyncServerStreamingCall(
+          getChannel().newCall(getQueryActiveAlarmsMethod(), getCallOptions()), request, responseObserver);
+    }
  }

  /**
@@ -477,6 +543,25 @@ public final class MxAccessGatewayGrpc {
      return io.grpc.stub.ClientCalls.blockingV2ServerStreamingCall(
          getChannel(), getStreamAlarmsMethod(), getCallOptions(), request);
    }
+
+    /**
+     * <pre>
+     * Point-in-time snapshot of the currently-active alarm set served from the
+     * gateway's always-on alarm monitor cache (session-less). Used after a
+     * reconnect to seed Part 9 client state, or to reconcile alarms that may
+     * have been missed during a transport blip. Streamed so callers can
+     * begin processing without buffering the full set.
+     * `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+     * snapshot to alarms whose `alarm_full_reference` starts with the given
+     * prefix; an empty prefix returns the full set.
+     * </pre>
+     */
+    @io.grpc.ExperimentalApi("https://github.com/grpc/grpc-java/issues/10918")
+    public io.grpc.stub.BlockingClientCall<?, mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot>
+        queryActiveAlarms(mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request) {
+      return io.grpc.stub.ClientCalls.blockingV2ServerStreamingCall(
+          getChannel(), getQueryActiveAlarmsMethod(), getCallOptions(), request);
+    }
  }

  /**
@@ -548,6 +633,24 @@ public final class MxAccessGatewayGrpc {
      return io.grpc.stub.ClientCalls.blockingServerStreamingCall(
          getChannel(), getStreamAlarmsMethod(), getCallOptions(), request);
    }
+
+    /**
+     * <pre>
+     * Point-in-time snapshot of the currently-active alarm set served from the
+     * gateway's always-on alarm monitor cache (session-less). Used after a
+     * reconnect to seed Part 9 client state, or to reconcile alarms that may
+     * have been missed during a transport blip. Streamed so callers can
+     * begin processing without buffering the full set.
+     * `QueryActiveAlarmsRequest.alarm_filter_prefix` optionally narrows the
+     * snapshot to alarms whose `alarm_full_reference` starts with the given
+     * prefix; an empty prefix returns the full set.
+     * </pre>
+     */
+    public java.util.Iterator<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> queryActiveAlarms(
+        mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request) {
+      return io.grpc.stub.ClientCalls.blockingServerStreamingCall(
+          getChannel(), getQueryActiveAlarmsMethod(), getCallOptions(), request);
+    }
  }

  /**
@@ -608,6 +711,7 @@ public final class MxAccessGatewayGrpc {
  private static final int METHODID_STREAM_EVENTS = 3;
  private static final int METHODID_ACKNOWLEDGE_ALARM = 4;
  private static final int METHODID_STREAM_ALARMS = 5;
+  private static final int METHODID_QUERY_ACTIVE_ALARMS = 6;

  private static final class MethodHandlers<Req, Resp> implements
      io.grpc.stub.ServerCalls.UnaryMethod<Req, Resp>,
@@ -650,6 +754,10 @@ public final class MxAccessGatewayGrpc {
          serviceImpl.streamAlarms((mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest) request,
              (io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>) responseObserver);
          break;
+        case METHODID_QUERY_ACTIVE_ALARMS:
+          serviceImpl.queryActiveAlarms((mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest) request,
+              (io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot>) responseObserver);
+          break;
        default:
          throw new AssertionError();
      }
@@ -710,6 +818,13 @@ public final class MxAccessGatewayGrpc {
              mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest,
              mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>(
                service, METHODID_STREAM_ALARMS)))
+        .addMethod(
+          getQueryActiveAlarmsMethod(),
+          io.grpc.stub.ServerCalls.asyncServerStreamingCall(
+            new MethodHandlers<
+              mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest,
+              mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot>(
+                service, METHODID_QUERY_ACTIVE_ALARMS)))
        .build();
  }

@@ -764,6 +879,7 @@ public final class MxAccessGatewayGrpc {
              .addMethod(getStreamEventsMethod())
              .addMethod(getAcknowledgeAlarmMethod())
              .addMethod(getStreamAlarmsMethod())
+              .addMethod(getQueryActiveAlarmsMethod())
              .build();
        }
      }
--- a/Show More
+++ b/Show More