Remove the AlarmClientDiscovery probe log

Delete docs/AlarmClientDiscovery.md — an archival AVEVA alarm-consumer investigation log whose durable findings now live in the alarm worker/monitor code. Drop the now-dangling links from Grpc.md and GatewayConfiguration.md. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Document the session-less StreamAlarms feed and alarm config
2026-05-21 17:04:29 -04:00 · 2026-05-21 16:59:48 -04:00 · 2026-05-21 16:55:20 -04:00 · 2026-05-21 16:49:26 -04:00 · 2026-05-21 16:45:53 -04:00 · 2026-05-21 16:45:47 -04:00
23 changed files with 2360 additions and 2216 deletions
@@ -687,18 +687,32 @@ func (x *GalaxyObject) GetAttributes() []*GalaxyAttribute {
 }

 type GalaxyAttribute struct {
-	state                  protoimpl.MessageState `protogen:"open.v1"`
-	AttributeName          string                 `protobuf:"bytes,1,opt,name=attribute_name,json=attributeName,proto3" json:"attribute_name,omitempty"`
-	FullTagReference       string                 `protobuf:"bytes,2,opt,name=full_tag_reference,json=fullTagReference,proto3" json:"full_tag_reference,omitempty"`
-	MxDataType             int32                  `protobuf:"varint,3,opt,name=mx_data_type,json=mxDataType,proto3" json:"mx_data_type,omitempty"`
-	DataTypeName           string                 `protobuf:"bytes,4,opt,name=data_type_name,json=dataTypeName,proto3" json:"data_type_name,omitempty"`
-	IsArray                bool                   `protobuf:"varint,5,opt,name=is_array,json=isArray,proto3" json:"is_array,omitempty"`
-	ArrayDimension         int32                  `protobuf:"varint,6,opt,name=array_dimension,json=arrayDimension,proto3" json:"array_dimension,omitempty"`
-	ArrayDimensionPresent  bool                   `protobuf:"varint,7,opt,name=array_dimension_present,json=arrayDimensionPresent,proto3" json:"array_dimension_present,omitempty"`
-	MxAttributeCategory    int32                  `protobuf:"varint,8,opt,name=mx_attribute_category,json=mxAttributeCategory,proto3" json:"mx_attribute_category,omitempty"`
-	SecurityClassification int32                  `protobuf:"varint,9,opt,name=security_classification,json=securityClassification,proto3" json:"security_classification,omitempty"`
-	IsHistorized           bool                   `protobuf:"varint,10,opt,name=is_historized,json=isHistorized,proto3" json:"is_historized,omitempty"`
-	IsAlarm                bool                   `protobuf:"varint,11,opt,name=is_alarm,json=isAlarm,proto3" json:"is_alarm,omitempty"`
+	state            protoimpl.MessageState `protogen:"open.v1"`
+	AttributeName    string                 `protobuf:"bytes,1,opt,name=attribute_name,json=attributeName,proto3" json:"attribute_name,omitempty"`
+	FullTagReference string                 `protobuf:"bytes,2,opt,name=full_tag_reference,json=fullTagReference,proto3" json:"full_tag_reference,omitempty"`
+	// Raw Galaxy SQL `dbo.data_type` identifier, passed through unchanged.
+	// This is NOT a member of `mxaccess_gateway.v1.MxDataType` — Galaxy's
+	// type enumeration is distinct from MXAccess's wire data-type enum and
+	// the two must not be cast or compared. The GalaxyRepository service is
+	// metadata-only and deliberately does not share types with
+	// mxaccess_gateway.proto. See docs/GalaxyRepository.md.
+	MxDataType int32 `protobuf:"varint,3,opt,name=mx_data_type,json=mxDataType,proto3" json:"mx_data_type,omitempty"`
+	// Human-readable name from Galaxy's `dbo.data_type` table (e.g. "Float",
+	// "Integer", "Boolean"). Free-form Galaxy text; not a stable enum.
+	DataTypeName          string `protobuf:"bytes,4,opt,name=data_type_name,json=dataTypeName,proto3" json:"data_type_name,omitempty"`
+	IsArray               bool   `protobuf:"varint,5,opt,name=is_array,json=isArray,proto3" json:"is_array,omitempty"`
+	ArrayDimension        int32  `protobuf:"varint,6,opt,name=array_dimension,json=arrayDimension,proto3" json:"array_dimension,omitempty"`
+	ArrayDimensionPresent bool   `protobuf:"varint,7,opt,name=array_dimension_present,json=arrayDimensionPresent,proto3" json:"array_dimension_present,omitempty"`
+	// Raw Galaxy SQL attribute-category identifier, passed through unchanged.
+	// Galaxy-specific; not mapped to any gateway enum. See
+	// docs/GalaxyRepository.md.
+	MxAttributeCategory int32 `protobuf:"varint,8,opt,name=mx_attribute_category,json=mxAttributeCategory,proto3" json:"mx_attribute_category,omitempty"`
+	// Raw Galaxy SQL security-classification identifier, passed through
+	// unchanged. Galaxy-specific; not mapped to any gateway enum. See
+	// docs/GalaxyRepository.md.
+	SecurityClassification int32 `protobuf:"varint,9,opt,name=security_classification,json=securityClassification,proto3" json:"security_classification,omitempty"`
+	IsHistorized           bool  `protobuf:"varint,10,opt,name=is_historized,json=isHistorized,proto3" json:"is_historized,omitempty"`
+	IsAlarm                bool  `protobuf:"varint,11,opt,name=is_alarm,json=isAlarm,proto3" json:"is_alarm,omitempty"`
 	unknownFields          protoimpl.UnknownFields
 	sizeCache              protoimpl.SizeCache
 }
@@ -3792,9 +3792,11 @@ type WriteSecuredBulkEntry struct {
 	ItemHandle     int32                  `protobuf:"varint,1,opt,name=item_handle,json=itemHandle,proto3" json:"item_handle,omitempty"`
 	CurrentUserId  int32                  `protobuf:"varint,2,opt,name=current_user_id,json=currentUserId,proto3" json:"current_user_id,omitempty"`
 	VerifierUserId int32                  `protobuf:"varint,3,opt,name=verifier_user_id,json=verifierUserId,proto3" json:"verifier_user_id,omitempty"`
-	Value          *MxValue               `protobuf:"bytes,4,opt,name=value,proto3" json:"value,omitempty"`
-	unknownFields  protoimpl.UnknownFields
-	sizeCache      protoimpl.SizeCache
+	// Credential-sensitive write value. Implementations must not log this field
+	// unless an explicit redacted value-logging path is enabled.
+	Value         *MxValue `protobuf:"bytes,4,opt,name=value,proto3" json:"value,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
 }

 func (x *WriteSecuredBulkEntry) Reset() {
@@ -3914,8 +3916,10 @@ type WriteSecured2BulkEntry struct {
 	ItemHandle     int32                  `protobuf:"varint,1,opt,name=item_handle,json=itemHandle,proto3" json:"item_handle,omitempty"`
 	CurrentUserId  int32                  `protobuf:"varint,2,opt,name=current_user_id,json=currentUserId,proto3" json:"current_user_id,omitempty"`
 	VerifierUserId int32                  `protobuf:"varint,3,opt,name=verifier_user_id,json=verifierUserId,proto3" json:"verifier_user_id,omitempty"`
-	Value          *MxValue               `protobuf:"bytes,4,opt,name=value,proto3" json:"value,omitempty"`
-	TimestampValue *MxValue               `protobuf:"bytes,5,opt,name=timestamp_value,json=timestampValue,proto3" json:"timestamp_value,omitempty"`
+	// Credential-sensitive write value. Implementations must not log this field
+	// unless an explicit redacted value-logging path is enabled.
+	Value          *MxValue `protobuf:"bytes,4,opt,name=value,proto3" json:"value,omitempty"`
+	TimestampValue *MxValue `protobuf:"bytes,5,opt,name=timestamp_value,json=timestampValue,proto3" json:"timestamp_value,omitempty"`
 	unknownFields  protoimpl.UnknownFields
 	sizeCache      protoimpl.SizeCache
 }
@@ -3987,6 +3991,7 @@ func (x *WriteSecured2BulkEntry) GetTimestampValue() *MxValue {

 // Bulk Read — snapshot the current value for each requested tag. MXAccess COM
 // has no synchronous Read; the worker implements ReadBulk as:
+//
 //   - If the tag is already in the session's item registry AND that item is
 //     currently advised AND the worker has a cached OnDataChange for it, the
 //     reply returns the cached value WITHOUT modifying the existing
@@ -5245,9 +5250,11 @@ func (x *BulkSubscribeReply) GetResults() []*SubscribeResult {

 // Per-item result for the four bulk write families. `item_handle` mirrors the
 // request entry's item_handle so callers can correlate inputs to outputs even
-// when the gateway's tag-allowlist filter dropped some entries before reaching
-// the worker. Per-item failures populate `error_message` + `hresult` and never
-// raise — callers iterate and inspect each entry.
+// when the gateway's per-entry `IConstraintEnforcer.CheckWriteHandleAsync`
+// filter (see `MxAccessGatewayService.ReplaceWriteBulkEntries` and
+// `docs/Authorization.md`) dropped some entries before reaching the worker.
+// Per-item failures populate `error_message` + `hresult` and never raise —
+// callers iterate and inspect each entry.
 type BulkWriteResult struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
 	ServerHandle  int32                  `protobuf:"varint,1,opt,name=server_handle,json=serverHandle,proto3" json:"server_handle,omitempty"`
@@ -5380,6 +5387,20 @@ func (x *BulkWriteReply) GetResults() []*BulkWriteResult {
 // an existing live subscription's last OnDataChange (the worker did not touch
 // the subscription); false when the worker took the AddItem + Advise + wait +
 // UnAdvise + RemoveItem snapshot lifecycle itself.
+//
+// On `was_successful = true`, `value`, `quality`, `source_timestamp`, and
+// `statuses` carry the read data (from the cached subscription or the snapshot
+// lifecycle, depending on `was_cached`) and `error_message` is empty. On
+// `was_successful = false`, only `server_handle`, `tag_address`, `item_handle`
+// (when allocated), `was_cached`, and `error_message` are populated; `value`,
+// `quality`, `source_timestamp`, and `statuses` are left at their proto3
+// defaults (null / 0 / null / empty) and must not be read as data — they are
+// wire-indistinguishable from "value is null with quality bad" data and serve
+// only as absent markers. ReadBulk has no `hresult` field by design (its
+// outcomes are timeout / cache / lifecycle states, not MXAccess COM return
+// codes — see `docs/DesignDecisions.md` "Bulk Command Family"). Per-tag
+// failures populate `error_message` and never raise — callers iterate and
+// inspect each entry.
 type BulkReadResult struct {
 	state           protoimpl.MessageState `protogen:"open.v1"`
 	ServerHandle    int32                  `protobuf:"varint,1,opt,name=server_handle,json=serverHandle,proto3" json:"server_handle,omitempty"`
@@ -6528,7 +6549,6 @@ func (x *ActiveAlarmSnapshot) GetLimitValue() *MxValue {

 type AcknowledgeAlarmRequest struct {
 	state               protoimpl.MessageState `protogen:"open.v1"`
-	SessionId           string                 `protobuf:"bytes,1,opt,name=session_id,json=sessionId,proto3" json:"session_id,omitempty"`
 	ClientCorrelationId string                 `protobuf:"bytes,2,opt,name=client_correlation_id,json=clientCorrelationId,proto3" json:"client_correlation_id,omitempty"`
 	// Fully-qualified alarm reference matching OnAlarmTransitionEvent.alarm_full_reference.
 	AlarmFullReference string `protobuf:"bytes,3,opt,name=alarm_full_reference,json=alarmFullReference,proto3" json:"alarm_full_reference,omitempty"`
@@ -6571,13 +6591,6 @@ func (*AcknowledgeAlarmRequest) Descriptor() ([]byte, []int) {
 	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{77}
 }

-func (x *AcknowledgeAlarmRequest) GetSessionId() string {
-	if x != nil {
-		return x.SessionId
-	}
-	return ""
-}
-
 func (x *AcknowledgeAlarmRequest) GetClientCorrelationId() string {
 	if x != nil {
 		return x.ClientCorrelationId
@@ -6608,7 +6621,6 @@ func (x *AcknowledgeAlarmRequest) GetOperatorUser() string {

 type AcknowledgeAlarmReply struct {
 	state          protoimpl.MessageState `protogen:"open.v1"`
-	SessionId      string                 `protobuf:"bytes,1,opt,name=session_id,json=sessionId,proto3" json:"session_id,omitempty"`
 	CorrelationId  string                 `protobuf:"bytes,2,opt,name=correlation_id,json=correlationId,proto3" json:"correlation_id,omitempty"`
 	ProtocolStatus *ProtocolStatus        `protobuf:"bytes,3,opt,name=protocol_status,json=protocolStatus,proto3" json:"protocol_status,omitempty"`
 	// Native ack return code echoed from the worker. The worker carries the
@@ -6659,13 +6671,6 @@ func (*AcknowledgeAlarmReply) Descriptor() ([]byte, []int) {
 	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{78}
 }

-func (x *AcknowledgeAlarmReply) GetSessionId() string {
-	if x != nil {
-		return x.SessionId
-	}
-	return ""
-}
-
 func (x *AcknowledgeAlarmReply) GetCorrelationId() string {
 	if x != nil {
 		return x.CorrelationId
@@ -6701,31 +6706,31 @@ func (x *AcknowledgeAlarmReply) GetDiagnosticMessage() string {
 	return ""
 }

-type QueryActiveAlarmsRequest struct {
+// Request to attach to the gateway's central alarm feed (StreamAlarms).
+type StreamAlarmsRequest struct {
 	state               protoimpl.MessageState `protogen:"open.v1"`
-	SessionId           string                 `protobuf:"bytes,1,opt,name=session_id,json=sessionId,proto3" json:"session_id,omitempty"`
-	ClientCorrelationId string                 `protobuf:"bytes,2,opt,name=client_correlation_id,json=clientCorrelationId,proto3" json:"client_correlation_id,omitempty"`
-	// Optional alarm-reference prefix used to scope a partial ConditionRefresh
-	// (e.g. equipment sub-tree). Empty means full refresh.
-	AlarmFilterPrefix string `protobuf:"bytes,3,opt,name=alarm_filter_prefix,json=alarmFilterPrefix,proto3" json:"alarm_filter_prefix,omitempty"`
+	ClientCorrelationId string                 `protobuf:"bytes,1,opt,name=client_correlation_id,json=clientCorrelationId,proto3" json:"client_correlation_id,omitempty"`
+	// Optional alarm-reference prefix scoping the feed to an equipment
+	// sub-tree. Empty streams every active alarm.
+	AlarmFilterPrefix string `protobuf:"bytes,2,opt,name=alarm_filter_prefix,json=alarmFilterPrefix,proto3" json:"alarm_filter_prefix,omitempty"`
 	unknownFields     protoimpl.UnknownFields
 	sizeCache         protoimpl.SizeCache
 }

-func (x *QueryActiveAlarmsRequest) Reset() {
-	*x = QueryActiveAlarmsRequest{}
+func (x *StreamAlarmsRequest) Reset() {
+	*x = StreamAlarmsRequest{}
 	mi := &file_mxaccess_gateway_proto_msgTypes[79]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }

-func (x *QueryActiveAlarmsRequest) String() string {
+func (x *StreamAlarmsRequest) String() string {
 	return protoimpl.X.MessageStringOf(x)
 }

-func (*QueryActiveAlarmsRequest) ProtoMessage() {}
+func (*StreamAlarmsRequest) ProtoMessage() {}

-func (x *QueryActiveAlarmsRequest) ProtoReflect() protoreflect.Message {
+func (x *StreamAlarmsRequest) ProtoReflect() protoreflect.Message {
 	mi := &file_mxaccess_gateway_proto_msgTypes[79]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
@@ -6737,32 +6742,130 @@ func (x *QueryActiveAlarmsRequest) ProtoReflect() protoreflect.Message {
 	return mi.MessageOf(x)
 }

-// Deprecated: Use QueryActiveAlarmsRequest.ProtoReflect.Descriptor instead.
-func (*QueryActiveAlarmsRequest) Descriptor() ([]byte, []int) {
+// Deprecated: Use StreamAlarmsRequest.ProtoReflect.Descriptor instead.
+func (*StreamAlarmsRequest) Descriptor() ([]byte, []int) {
 	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{79}
 }

-func (x *QueryActiveAlarmsRequest) GetSessionId() string {
-	if x != nil {
-		return x.SessionId
-	}
-	return ""
-}
-
-func (x *QueryActiveAlarmsRequest) GetClientCorrelationId() string {
+func (x *StreamAlarmsRequest) GetClientCorrelationId() string {
 	if x != nil {
 		return x.ClientCorrelationId
 	}
 	return ""
 }

-func (x *QueryActiveAlarmsRequest) GetAlarmFilterPrefix() string {
+func (x *StreamAlarmsRequest) GetAlarmFilterPrefix() string {
 	if x != nil {
 		return x.AlarmFilterPrefix
 	}
 	return ""
 }

+// One message on the StreamAlarms feed. The stream opens with one
+// `active_alarm` per currently-active alarm, then a single
+// `snapshot_complete`, then a `transition` for every subsequent change.
+type AlarmFeedMessage struct {
+	state protoimpl.MessageState `protogen:"open.v1"`
+	// Types that are valid to be assigned to Payload:
+	//
+	//	*AlarmFeedMessage_ActiveAlarm
+	//	*AlarmFeedMessage_SnapshotComplete
+	//	*AlarmFeedMessage_Transition
+	Payload       isAlarmFeedMessage_Payload `protobuf_oneof:"payload"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *AlarmFeedMessage) Reset() {
+	*x = AlarmFeedMessage{}
+	mi := &file_mxaccess_gateway_proto_msgTypes[80]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *AlarmFeedMessage) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*AlarmFeedMessage) ProtoMessage() {}
+
+func (x *AlarmFeedMessage) ProtoReflect() protoreflect.Message {
+	mi := &file_mxaccess_gateway_proto_msgTypes[80]
+	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 AlarmFeedMessage.ProtoReflect.Descriptor instead.
+func (*AlarmFeedMessage) Descriptor() ([]byte, []int) {
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{80}
+}
+
+func (x *AlarmFeedMessage) GetPayload() isAlarmFeedMessage_Payload {
+	if x != nil {
+		return x.Payload
+	}
+	return nil
+}
+
+func (x *AlarmFeedMessage) GetActiveAlarm() *ActiveAlarmSnapshot {
+	if x != nil {
+		if x, ok := x.Payload.(*AlarmFeedMessage_ActiveAlarm); ok {
+			return x.ActiveAlarm
+		}
+	}
+	return nil
+}
+
+func (x *AlarmFeedMessage) GetSnapshotComplete() bool {
+	if x != nil {
+		if x, ok := x.Payload.(*AlarmFeedMessage_SnapshotComplete); ok {
+			return x.SnapshotComplete
+		}
+	}
+	return false
+}
+
+func (x *AlarmFeedMessage) GetTransition() *OnAlarmTransitionEvent {
+	if x != nil {
+		if x, ok := x.Payload.(*AlarmFeedMessage_Transition); ok {
+			return x.Transition
+		}
+	}
+	return nil
+}
+
+type isAlarmFeedMessage_Payload interface {
+	isAlarmFeedMessage_Payload()
+}
+
+type AlarmFeedMessage_ActiveAlarm struct {
+	// Part of the initial active-alarm snapshot (ConditionRefresh).
+	ActiveAlarm *ActiveAlarmSnapshot `protobuf:"bytes,1,opt,name=active_alarm,json=activeAlarm,proto3,oneof"`
+}
+
+type AlarmFeedMessage_SnapshotComplete struct {
+	// Sentinel: the initial snapshot is fully delivered and `transition`
+	// messages follow. Always true when present.
+	SnapshotComplete bool `protobuf:"varint,2,opt,name=snapshot_complete,json=snapshotComplete,proto3,oneof"`
+}
+
+type AlarmFeedMessage_Transition struct {
+	// A live alarm state change (raise / acknowledge / clear).
+	Transition *OnAlarmTransitionEvent `protobuf:"bytes,3,opt,name=transition,proto3,oneof"`
+}
+
+func (*AlarmFeedMessage_ActiveAlarm) isAlarmFeedMessage_Payload() {}
+
+func (*AlarmFeedMessage_SnapshotComplete) isAlarmFeedMessage_Payload() {}
+
+func (*AlarmFeedMessage_Transition) isAlarmFeedMessage_Payload() {}
+
 type MxStatusProxy struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// Mirrors the `success` member of the MXAccess MXSTATUS_PROXY struct
@@ -6787,7 +6890,7 @@ type MxStatusProxy struct {

 func (x *MxStatusProxy) Reset() {
 	*x = MxStatusProxy{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[80]
+	mi := &file_mxaccess_gateway_proto_msgTypes[81]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -6799,7 +6902,7 @@ func (x *MxStatusProxy) String() string {
 func (*MxStatusProxy) ProtoMessage() {}

 func (x *MxStatusProxy) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[80]
+	mi := &file_mxaccess_gateway_proto_msgTypes[81]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -6812,7 +6915,7 @@ func (x *MxStatusProxy) ProtoReflect() protoreflect.Message {

 // Deprecated: Use MxStatusProxy.ProtoReflect.Descriptor instead.
 func (*MxStatusProxy) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{80}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{81}
 }

 func (x *MxStatusProxy) GetSuccess() int32 {
@@ -6889,7 +6992,7 @@ type MxValue struct {

 func (x *MxValue) Reset() {
 	*x = MxValue{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[81]
+	mi := &file_mxaccess_gateway_proto_msgTypes[82]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -6901,7 +7004,7 @@ func (x *MxValue) String() string {
 func (*MxValue) ProtoMessage() {}

 func (x *MxValue) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[81]
+	mi := &file_mxaccess_gateway_proto_msgTypes[82]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -6914,7 +7017,7 @@ func (x *MxValue) ProtoReflect() protoreflect.Message {

 // Deprecated: Use MxValue.ProtoReflect.Descriptor instead.
 func (*MxValue) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{81}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{82}
 }

 func (x *MxValue) GetDataType() MxDataType {
@@ -7122,7 +7225,7 @@ type MxArray struct {

 func (x *MxArray) Reset() {
 	*x = MxArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[82]
+	mi := &file_mxaccess_gateway_proto_msgTypes[83]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7134,7 +7237,7 @@ func (x *MxArray) String() string {
 func (*MxArray) ProtoMessage() {}

 func (x *MxArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[82]
+	mi := &file_mxaccess_gateway_proto_msgTypes[83]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7147,7 +7250,7 @@ func (x *MxArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use MxArray.ProtoReflect.Descriptor instead.
 func (*MxArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{82}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{83}
 }

 func (x *MxArray) GetElementDataType() MxDataType {
@@ -7325,7 +7428,7 @@ type BoolArray struct {

 func (x *BoolArray) Reset() {
 	*x = BoolArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[83]
+	mi := &file_mxaccess_gateway_proto_msgTypes[84]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7337,7 +7440,7 @@ func (x *BoolArray) String() string {
 func (*BoolArray) ProtoMessage() {}

 func (x *BoolArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[83]
+	mi := &file_mxaccess_gateway_proto_msgTypes[84]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7350,7 +7453,7 @@ func (x *BoolArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use BoolArray.ProtoReflect.Descriptor instead.
 func (*BoolArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{83}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{84}
 }

 func (x *BoolArray) GetValues() []bool {
@@ -7369,7 +7472,7 @@ type Int32Array struct {

 func (x *Int32Array) Reset() {
 	*x = Int32Array{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[84]
+	mi := &file_mxaccess_gateway_proto_msgTypes[85]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7381,7 +7484,7 @@ func (x *Int32Array) String() string {
 func (*Int32Array) ProtoMessage() {}

 func (x *Int32Array) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[84]
+	mi := &file_mxaccess_gateway_proto_msgTypes[85]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7394,7 +7497,7 @@ func (x *Int32Array) ProtoReflect() protoreflect.Message {

 // Deprecated: Use Int32Array.ProtoReflect.Descriptor instead.
 func (*Int32Array) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{84}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{85}
 }

 func (x *Int32Array) GetValues() []int32 {
@@ -7413,7 +7516,7 @@ type Int64Array struct {

 func (x *Int64Array) Reset() {
 	*x = Int64Array{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[85]
+	mi := &file_mxaccess_gateway_proto_msgTypes[86]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7425,7 +7528,7 @@ func (x *Int64Array) String() string {
 func (*Int64Array) ProtoMessage() {}

 func (x *Int64Array) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[85]
+	mi := &file_mxaccess_gateway_proto_msgTypes[86]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7438,7 +7541,7 @@ func (x *Int64Array) ProtoReflect() protoreflect.Message {

 // Deprecated: Use Int64Array.ProtoReflect.Descriptor instead.
 func (*Int64Array) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{85}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{86}
 }

 func (x *Int64Array) GetValues() []int64 {
@@ -7457,7 +7560,7 @@ type FloatArray struct {

 func (x *FloatArray) Reset() {
 	*x = FloatArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[86]
+	mi := &file_mxaccess_gateway_proto_msgTypes[87]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7469,7 +7572,7 @@ func (x *FloatArray) String() string {
 func (*FloatArray) ProtoMessage() {}

 func (x *FloatArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[86]
+	mi := &file_mxaccess_gateway_proto_msgTypes[87]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7482,7 +7585,7 @@ func (x *FloatArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use FloatArray.ProtoReflect.Descriptor instead.
 func (*FloatArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{86}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{87}
 }

 func (x *FloatArray) GetValues() []float32 {
@@ -7501,7 +7604,7 @@ type DoubleArray struct {

 func (x *DoubleArray) Reset() {
 	*x = DoubleArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[87]
+	mi := &file_mxaccess_gateway_proto_msgTypes[88]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7513,7 +7616,7 @@ func (x *DoubleArray) String() string {
 func (*DoubleArray) ProtoMessage() {}

 func (x *DoubleArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[87]
+	mi := &file_mxaccess_gateway_proto_msgTypes[88]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7526,7 +7629,7 @@ func (x *DoubleArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use DoubleArray.ProtoReflect.Descriptor instead.
 func (*DoubleArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{87}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{88}
 }

 func (x *DoubleArray) GetValues() []float64 {
@@ -7545,7 +7648,7 @@ type StringArray struct {

 func (x *StringArray) Reset() {
 	*x = StringArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[88]
+	mi := &file_mxaccess_gateway_proto_msgTypes[89]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7557,7 +7660,7 @@ func (x *StringArray) String() string {
 func (*StringArray) ProtoMessage() {}

 func (x *StringArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[88]
+	mi := &file_mxaccess_gateway_proto_msgTypes[89]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7570,7 +7673,7 @@ func (x *StringArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use StringArray.ProtoReflect.Descriptor instead.
 func (*StringArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{88}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{89}
 }

 func (x *StringArray) GetValues() []string {
@@ -7589,7 +7692,7 @@ type TimestampArray struct {

 func (x *TimestampArray) Reset() {
 	*x = TimestampArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[89]
+	mi := &file_mxaccess_gateway_proto_msgTypes[90]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7601,7 +7704,7 @@ func (x *TimestampArray) String() string {
 func (*TimestampArray) ProtoMessage() {}

 func (x *TimestampArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[89]
+	mi := &file_mxaccess_gateway_proto_msgTypes[90]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7614,7 +7717,7 @@ func (x *TimestampArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use TimestampArray.ProtoReflect.Descriptor instead.
 func (*TimestampArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{89}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{90}
 }

 func (x *TimestampArray) GetValues() []*timestamppb.Timestamp {
@@ -7633,7 +7736,7 @@ type RawArray struct {

 func (x *RawArray) Reset() {
 	*x = RawArray{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[90]
+	mi := &file_mxaccess_gateway_proto_msgTypes[91]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7645,7 +7748,7 @@ func (x *RawArray) String() string {
 func (*RawArray) ProtoMessage() {}

 func (x *RawArray) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[90]
+	mi := &file_mxaccess_gateway_proto_msgTypes[91]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7658,7 +7761,7 @@ func (x *RawArray) ProtoReflect() protoreflect.Message {

 // Deprecated: Use RawArray.ProtoReflect.Descriptor instead.
 func (*RawArray) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{90}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{91}
 }

 func (x *RawArray) GetValues() [][]byte {
@@ -7678,7 +7781,7 @@ type ProtocolStatus struct {

 func (x *ProtocolStatus) Reset() {
 	*x = ProtocolStatus{}
-	mi := &file_mxaccess_gateway_proto_msgTypes[91]
+	mi := &file_mxaccess_gateway_proto_msgTypes[92]
 	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 	ms.StoreMessageInfo(mi)
 }
@@ -7690,7 +7793,7 @@ func (x *ProtocolStatus) String() string {
 func (*ProtocolStatus) ProtoMessage() {}

 func (x *ProtocolStatus) ProtoReflect() protoreflect.Message {
-	mi := &file_mxaccess_gateway_proto_msgTypes[91]
+	mi := &file_mxaccess_gateway_proto_msgTypes[92]
 	if x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -7703,7 +7806,7 @@ func (x *ProtocolStatus) ProtoReflect() protoreflect.Message {

 // Deprecated: Use ProtocolStatus.ProtoReflect.Descriptor instead.
 func (*ProtocolStatus) Descriptor() ([]byte, []int) {
-	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{91}
+	return file_mxaccess_gateway_proto_rawDescGZIP(), []int{92}
 }

 func (x *ProtocolStatus) GetCode() ProtocolStatusCode {
@@ -8155,29 +8258,32 @@ const file_mxaccess_gateway_proto_rawDesc = "" +
 	"\x10operator_comment\x18\v \x01(\tR\x0foperatorComment\x12A\n" +
 	"\rcurrent_value\x18\f \x01(\v2\x1c.mxaccess_gateway.v1.MxValueR\fcurrentValue\x12=\n" +
 	"\vlimit_value\x18\r \x01(\v2\x1c.mxaccess_gateway.v1.MxValueR\n" +
-	"limitValue\"\xdd\x01\n" +
-	"\x17AcknowledgeAlarmRequest\x12\x1d\n" +
-	"\n" +
-	"session_id\x18\x01 \x01(\tR\tsessionId\x122\n" +
+	"limitValue\"\xd0\x01\n" +
+	"\x17AcknowledgeAlarmRequest\x122\n" +
 	"\x15client_correlation_id\x18\x02 \x01(\tR\x13clientCorrelationId\x120\n" +
 	"\x14alarm_full_reference\x18\x03 \x01(\tR\x12alarmFullReference\x12\x18\n" +
 	"\acomment\x18\x04 \x01(\tR\acomment\x12#\n" +
-	"\roperator_user\x18\x05 \x01(\tR\foperatorUser\"\xc1\x02\n" +
-	"\x15AcknowledgeAlarmReply\x12\x1d\n" +
-	"\n" +
-	"session_id\x18\x01 \x01(\tR\tsessionId\x12%\n" +
+	"\roperator_user\x18\x05 \x01(\tR\foperatorUserJ\x04\b\x01\x10\x02R\n" +
+	"session_id\"\xb4\x02\n" +
+	"\x15AcknowledgeAlarmReply\x12%\n" +
 	"\x0ecorrelation_id\x18\x02 \x01(\tR\rcorrelationId\x12L\n" +
 	"\x0fprotocol_status\x18\x03 \x01(\v2#.mxaccess_gateway.v1.ProtocolStatusR\x0eprotocolStatus\x12\x1d\n" +
 	"\ahresult\x18\x04 \x01(\x05H\x00R\ahresult\x88\x01\x01\x12:\n" +
 	"\x06status\x18\x05 \x01(\v2\".mxaccess_gateway.v1.MxStatusProxyR\x06status\x12-\n" +
 	"\x12diagnostic_message\x18\x06 \x01(\tR\x11diagnosticMessageB\n" +
 	"\n" +
-	"\b_hresult\"\x9d\x01\n" +
-	"\x18QueryActiveAlarmsRequest\x12\x1d\n" +
+	"\b_hresultJ\x04\b\x01\x10\x02R\n" +
+	"session_id\"y\n" +
+	"\x13StreamAlarmsRequest\x122\n" +
+	"\x15client_correlation_id\x18\x01 \x01(\tR\x13clientCorrelationId\x12.\n" +
+	"\x13alarm_filter_prefix\x18\x02 \x01(\tR\x11alarmFilterPrefix\"\xea\x01\n" +
+	"\x10AlarmFeedMessage\x12M\n" +
+	"\factive_alarm\x18\x01 \x01(\v2(.mxaccess_gateway.v1.ActiveAlarmSnapshotH\x00R\vactiveAlarm\x12-\n" +
+	"\x11snapshot_complete\x18\x02 \x01(\bH\x00R\x10snapshotComplete\x12M\n" +
 	"\n" +
-	"session_id\x18\x01 \x01(\tR\tsessionId\x122\n" +
-	"\x15client_correlation_id\x18\x02 \x01(\tR\x13clientCorrelationId\x12.\n" +
-	"\x13alarm_filter_prefix\x18\x03 \x01(\tR\x11alarmFilterPrefix\"\xbe\x02\n" +
+	"transition\x18\x03 \x01(\v2+.mxaccess_gateway.v1.OnAlarmTransitionEventH\x00R\n" +
+	"transitionB\t\n" +
+	"\apayload\"\xbe\x02\n" +
 	"\rMxStatusProxy\x12\x18\n" +
 	"\asuccess\x18\x01 \x01(\x05R\asuccess\x12A\n" +
 	"\bcategory\x18\x02 \x01(\x0e2%.mxaccess_gateway.v1.MxStatusCategoryR\bcategory\x12D\n" +
@@ -8377,14 +8483,14 @@ const file_mxaccess_gateway_proto_rawDesc = "" +
 	"\x13SESSION_STATE_READY\x10\x06\x12\x19\n" +
 	"\x15SESSION_STATE_CLOSING\x10\a\x12\x18\n" +
 	"\x14SESSION_STATE_CLOSED\x10\b\x12\x19\n" +
-	"\x15SESSION_STATE_FAULTED\x10\t2\xe0\x04\n" +
+	"\x15SESSION_STATE_FAULTED\x10\t2\xd3\x04\n" +
 	"\x0fMxAccessGateway\x12]\n" +
 	"\vOpenSession\x12'.mxaccess_gateway.v1.OpenSessionRequest\x1a%.mxaccess_gateway.v1.OpenSessionReply\x12`\n" +
 	"\fCloseSession\x12(.mxaccess_gateway.v1.CloseSessionRequest\x1a&.mxaccess_gateway.v1.CloseSessionReply\x12T\n" +
 	"\x06Invoke\x12%.mxaccess_gateway.v1.MxCommandRequest\x1a#.mxaccess_gateway.v1.MxCommandReply\x12X\n" +
 	"\fStreamEvents\x12(.mxaccess_gateway.v1.StreamEventsRequest\x1a\x1c.mxaccess_gateway.v1.MxEvent0\x01\x12l\n" +
-	"\x10AcknowledgeAlarm\x12,.mxaccess_gateway.v1.AcknowledgeAlarmRequest\x1a*.mxaccess_gateway.v1.AcknowledgeAlarmReply\x12n\n" +
-	"\x11QueryActiveAlarms\x12-.mxaccess_gateway.v1.QueryActiveAlarmsRequest\x1a(.mxaccess_gateway.v1.ActiveAlarmSnapshot0\x01B\x1c\xaa\x02\x19MxGateway.Contracts.Protob\x06proto3"
+	"\x10AcknowledgeAlarm\x12,.mxaccess_gateway.v1.AcknowledgeAlarmRequest\x1a*.mxaccess_gateway.v1.AcknowledgeAlarmReply\x12a\n" +
+	"\fStreamAlarms\x12(.mxaccess_gateway.v1.StreamAlarmsRequest\x1a%.mxaccess_gateway.v1.AlarmFeedMessage0\x01B\x1c\xaa\x02\x19MxGateway.Contracts.Protob\x06proto3"

 var (
 	file_mxaccess_gateway_proto_rawDescOnce sync.Once
@@ -8399,7 +8505,7 @@ func file_mxaccess_gateway_proto_rawDescGZIP() []byte {
 }

 var file_mxaccess_gateway_proto_enumTypes = make([]protoimpl.EnumInfo, 9)
-var file_mxaccess_gateway_proto_msgTypes = make([]protoimpl.MessageInfo, 92)
+var file_mxaccess_gateway_proto_msgTypes = make([]protoimpl.MessageInfo, 93)
 var file_mxaccess_gateway_proto_goTypes = []any{
 	(MxCommandKind)(0),                       // 0: mxaccess_gateway.v1.MxCommandKind
 	(MxEventFamily)(0),                       // 1: mxaccess_gateway.v1.MxEventFamily
@@ -8489,28 +8595,29 @@ var file_mxaccess_gateway_proto_goTypes = []any{
 	(*ActiveAlarmSnapshot)(nil),              // 85: mxaccess_gateway.v1.ActiveAlarmSnapshot
 	(*AcknowledgeAlarmRequest)(nil),          // 86: mxaccess_gateway.v1.AcknowledgeAlarmRequest
 	(*AcknowledgeAlarmReply)(nil),            // 87: mxaccess_gateway.v1.AcknowledgeAlarmReply
-	(*QueryActiveAlarmsRequest)(nil),         // 88: mxaccess_gateway.v1.QueryActiveAlarmsRequest
-	(*MxStatusProxy)(nil),                    // 89: mxaccess_gateway.v1.MxStatusProxy
-	(*MxValue)(nil),                          // 90: mxaccess_gateway.v1.MxValue
-	(*MxArray)(nil),                          // 91: mxaccess_gateway.v1.MxArray
-	(*BoolArray)(nil),                        // 92: mxaccess_gateway.v1.BoolArray
-	(*Int32Array)(nil),                       // 93: mxaccess_gateway.v1.Int32Array
-	(*Int64Array)(nil),                       // 94: mxaccess_gateway.v1.Int64Array
-	(*FloatArray)(nil),                       // 95: mxaccess_gateway.v1.FloatArray
-	(*DoubleArray)(nil),                      // 96: mxaccess_gateway.v1.DoubleArray
-	(*StringArray)(nil),                      // 97: mxaccess_gateway.v1.StringArray
-	(*TimestampArray)(nil),                   // 98: mxaccess_gateway.v1.TimestampArray
-	(*RawArray)(nil),                         // 99: mxaccess_gateway.v1.RawArray
-	(*ProtocolStatus)(nil),                   // 100: mxaccess_gateway.v1.ProtocolStatus
-	(*durationpb.Duration)(nil),              // 101: google.protobuf.Duration
-	(*timestamppb.Timestamp)(nil),            // 102: google.protobuf.Timestamp
+	(*StreamAlarmsRequest)(nil),              // 88: mxaccess_gateway.v1.StreamAlarmsRequest
+	(*AlarmFeedMessage)(nil),                 // 89: mxaccess_gateway.v1.AlarmFeedMessage
+	(*MxStatusProxy)(nil),                    // 90: mxaccess_gateway.v1.MxStatusProxy
+	(*MxValue)(nil),                          // 91: mxaccess_gateway.v1.MxValue
+	(*MxArray)(nil),                          // 92: mxaccess_gateway.v1.MxArray
+	(*BoolArray)(nil),                        // 93: mxaccess_gateway.v1.BoolArray
+	(*Int32Array)(nil),                       // 94: mxaccess_gateway.v1.Int32Array
+	(*Int64Array)(nil),                       // 95: mxaccess_gateway.v1.Int64Array
+	(*FloatArray)(nil),                       // 96: mxaccess_gateway.v1.FloatArray
+	(*DoubleArray)(nil),                      // 97: mxaccess_gateway.v1.DoubleArray
+	(*StringArray)(nil),                      // 98: mxaccess_gateway.v1.StringArray
+	(*TimestampArray)(nil),                   // 99: mxaccess_gateway.v1.TimestampArray
+	(*RawArray)(nil),                         // 100: mxaccess_gateway.v1.RawArray
+	(*ProtocolStatus)(nil),                   // 101: mxaccess_gateway.v1.ProtocolStatus
+	(*durationpb.Duration)(nil),              // 102: google.protobuf.Duration
+	(*timestamppb.Timestamp)(nil),            // 103: google.protobuf.Timestamp
 }
 var file_mxaccess_gateway_proto_depIdxs = []int32{
-	101, // 0: mxaccess_gateway.v1.OpenSessionRequest.command_timeout:type_name -> google.protobuf.Duration
-	101, // 1: mxaccess_gateway.v1.OpenSessionReply.default_command_timeout:type_name -> google.protobuf.Duration
-	100, // 2: mxaccess_gateway.v1.OpenSessionReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
+	102, // 0: mxaccess_gateway.v1.OpenSessionRequest.command_timeout:type_name -> google.protobuf.Duration
+	102, // 1: mxaccess_gateway.v1.OpenSessionReply.default_command_timeout:type_name -> google.protobuf.Duration
+	101, // 2: mxaccess_gateway.v1.OpenSessionReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
 	8,   // 3: mxaccess_gateway.v1.CloseSessionReply.final_state:type_name -> mxaccess_gateway.v1.SessionState
-	100, // 4: mxaccess_gateway.v1.CloseSessionReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
+	101, // 4: mxaccess_gateway.v1.CloseSessionReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
 	15,  // 5: mxaccess_gateway.v1.MxCommandRequest.command:type_name -> mxaccess_gateway.v1.MxCommand
 	0,   // 6: mxaccess_gateway.v1.MxCommand.kind:type_name -> mxaccess_gateway.v1.MxCommandKind
 	16,  // 7: mxaccess_gateway.v1.MxCommand.register:type_name -> mxaccess_gateway.v1.RegisterCommand
@@ -8552,27 +8659,27 @@ var file_mxaccess_gateway_proto_depIdxs = []int32{
 	56,  // 43: mxaccess_gateway.v1.MxCommand.get_worker_info:type_name -> mxaccess_gateway.v1.GetWorkerInfoCommand
 	57,  // 44: mxaccess_gateway.v1.MxCommand.drain_events:type_name -> mxaccess_gateway.v1.DrainEventsCommand
 	58,  // 45: mxaccess_gateway.v1.MxCommand.shutdown_worker:type_name -> mxaccess_gateway.v1.ShutdownWorkerCommand
-	90,  // 46: mxaccess_gateway.v1.WriteCommand.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 47: mxaccess_gateway.v1.Write2Command.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 48: mxaccess_gateway.v1.Write2Command.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 49: mxaccess_gateway.v1.WriteSecuredCommand.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 50: mxaccess_gateway.v1.WriteSecured2Command.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 51: mxaccess_gateway.v1.WriteSecured2Command.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 46: mxaccess_gateway.v1.WriteCommand.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 47: mxaccess_gateway.v1.Write2Command.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 48: mxaccess_gateway.v1.Write2Command.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 49: mxaccess_gateway.v1.WriteSecuredCommand.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 50: mxaccess_gateway.v1.WriteSecured2Command.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 51: mxaccess_gateway.v1.WriteSecured2Command.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
 	46,  // 52: mxaccess_gateway.v1.WriteBulkCommand.entries:type_name -> mxaccess_gateway.v1.WriteBulkEntry
-	90,  // 53: mxaccess_gateway.v1.WriteBulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 53: mxaccess_gateway.v1.WriteBulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
 	48,  // 54: mxaccess_gateway.v1.Write2BulkCommand.entries:type_name -> mxaccess_gateway.v1.Write2BulkEntry
-	90,  // 55: mxaccess_gateway.v1.Write2BulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 56: mxaccess_gateway.v1.Write2BulkEntry.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 55: mxaccess_gateway.v1.Write2BulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 56: mxaccess_gateway.v1.Write2BulkEntry.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
 	50,  // 57: mxaccess_gateway.v1.WriteSecuredBulkCommand.entries:type_name -> mxaccess_gateway.v1.WriteSecuredBulkEntry
-	90,  // 58: mxaccess_gateway.v1.WriteSecuredBulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 58: mxaccess_gateway.v1.WriteSecuredBulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
 	52,  // 59: mxaccess_gateway.v1.WriteSecured2BulkCommand.entries:type_name -> mxaccess_gateway.v1.WriteSecured2BulkEntry
-	90,  // 60: mxaccess_gateway.v1.WriteSecured2BulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 61: mxaccess_gateway.v1.WriteSecured2BulkEntry.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
-	101, // 62: mxaccess_gateway.v1.ShutdownWorkerCommand.grace_period:type_name -> google.protobuf.Duration
+	91,  // 60: mxaccess_gateway.v1.WriteSecured2BulkEntry.value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 61: mxaccess_gateway.v1.WriteSecured2BulkEntry.timestamp_value:type_name -> mxaccess_gateway.v1.MxValue
+	102, // 62: mxaccess_gateway.v1.ShutdownWorkerCommand.grace_period:type_name -> google.protobuf.Duration
 	0,   // 63: mxaccess_gateway.v1.MxCommandReply.kind:type_name -> mxaccess_gateway.v1.MxCommandKind
-	100, // 64: mxaccess_gateway.v1.MxCommandReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
-	90,  // 65: mxaccess_gateway.v1.MxCommandReply.return_value:type_name -> mxaccess_gateway.v1.MxValue
-	89,  // 66: mxaccess_gateway.v1.MxCommandReply.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	101, // 64: mxaccess_gateway.v1.MxCommandReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
+	91,  // 65: mxaccess_gateway.v1.MxCommandReply.return_value:type_name -> mxaccess_gateway.v1.MxValue
+	90,  // 66: mxaccess_gateway.v1.MxCommandReply.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
 	60,  // 67: mxaccess_gateway.v1.MxCommandReply.register:type_name -> mxaccess_gateway.v1.RegisterReply
 	61,  // 68: mxaccess_gateway.v1.MxCommandReply.add_item:type_name -> mxaccess_gateway.v1.AddItemReply
 	62,  // 69: mxaccess_gateway.v1.MxCommandReply.add_item2:type_name -> mxaccess_gateway.v1.AddItem2Reply
@@ -8597,77 +8704,79 @@ var file_mxaccess_gateway_proto_depIdxs = []int32{
 	74,  // 88: mxaccess_gateway.v1.MxCommandReply.session_state:type_name -> mxaccess_gateway.v1.SessionStateReply
 	75,  // 89: mxaccess_gateway.v1.MxCommandReply.worker_info:type_name -> mxaccess_gateway.v1.WorkerInfoReply
 	76,  // 90: mxaccess_gateway.v1.MxCommandReply.drain_events:type_name -> mxaccess_gateway.v1.DrainEventsReply
-	89,  // 91: mxaccess_gateway.v1.SuspendReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
-	89,  // 92: mxaccess_gateway.v1.ActivateReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	90,  // 91: mxaccess_gateway.v1.SuspendReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	90,  // 92: mxaccess_gateway.v1.ActivateReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
 	68,  // 93: mxaccess_gateway.v1.BulkSubscribeReply.results:type_name -> mxaccess_gateway.v1.SubscribeResult
-	89,  // 94: mxaccess_gateway.v1.BulkWriteResult.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	90,  // 94: mxaccess_gateway.v1.BulkWriteResult.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
 	70,  // 95: mxaccess_gateway.v1.BulkWriteReply.results:type_name -> mxaccess_gateway.v1.BulkWriteResult
-	90,  // 96: mxaccess_gateway.v1.BulkReadResult.value:type_name -> mxaccess_gateway.v1.MxValue
-	102, // 97: mxaccess_gateway.v1.BulkReadResult.source_timestamp:type_name -> google.protobuf.Timestamp
-	89,  // 98: mxaccess_gateway.v1.BulkReadResult.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	91,  // 96: mxaccess_gateway.v1.BulkReadResult.value:type_name -> mxaccess_gateway.v1.MxValue
+	103, // 97: mxaccess_gateway.v1.BulkReadResult.source_timestamp:type_name -> google.protobuf.Timestamp
+	90,  // 98: mxaccess_gateway.v1.BulkReadResult.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
 	72,  // 99: mxaccess_gateway.v1.BulkReadReply.results:type_name -> mxaccess_gateway.v1.BulkReadResult
 	8,   // 100: mxaccess_gateway.v1.SessionStateReply.state:type_name -> mxaccess_gateway.v1.SessionState
 	79,  // 101: mxaccess_gateway.v1.DrainEventsReply.events:type_name -> mxaccess_gateway.v1.MxEvent
 	85,  // 102: mxaccess_gateway.v1.QueryActiveAlarmsReplyPayload.snapshots:type_name -> mxaccess_gateway.v1.ActiveAlarmSnapshot
 	1,   // 103: mxaccess_gateway.v1.MxEvent.family:type_name -> mxaccess_gateway.v1.MxEventFamily
-	90,  // 104: mxaccess_gateway.v1.MxEvent.value:type_name -> mxaccess_gateway.v1.MxValue
-	102, // 105: mxaccess_gateway.v1.MxEvent.source_timestamp:type_name -> google.protobuf.Timestamp
-	89,  // 106: mxaccess_gateway.v1.MxEvent.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
-	102, // 107: mxaccess_gateway.v1.MxEvent.worker_timestamp:type_name -> google.protobuf.Timestamp
-	102, // 108: mxaccess_gateway.v1.MxEvent.gateway_receive_timestamp:type_name -> google.protobuf.Timestamp
+	91,  // 104: mxaccess_gateway.v1.MxEvent.value:type_name -> mxaccess_gateway.v1.MxValue
+	103, // 105: mxaccess_gateway.v1.MxEvent.source_timestamp:type_name -> google.protobuf.Timestamp
+	90,  // 106: mxaccess_gateway.v1.MxEvent.statuses:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	103, // 107: mxaccess_gateway.v1.MxEvent.worker_timestamp:type_name -> google.protobuf.Timestamp
+	103, // 108: mxaccess_gateway.v1.MxEvent.gateway_receive_timestamp:type_name -> google.protobuf.Timestamp
 	80,  // 109: mxaccess_gateway.v1.MxEvent.on_data_change:type_name -> mxaccess_gateway.v1.OnDataChangeEvent
 	81,  // 110: mxaccess_gateway.v1.MxEvent.on_write_complete:type_name -> mxaccess_gateway.v1.OnWriteCompleteEvent
 	82,  // 111: mxaccess_gateway.v1.MxEvent.operation_complete:type_name -> mxaccess_gateway.v1.OperationCompleteEvent
 	83,  // 112: mxaccess_gateway.v1.MxEvent.on_buffered_data_change:type_name -> mxaccess_gateway.v1.OnBufferedDataChangeEvent
 	84,  // 113: mxaccess_gateway.v1.MxEvent.on_alarm_transition:type_name -> mxaccess_gateway.v1.OnAlarmTransitionEvent
 	6,   // 114: mxaccess_gateway.v1.OnBufferedDataChangeEvent.data_type:type_name -> mxaccess_gateway.v1.MxDataType
-	91,  // 115: mxaccess_gateway.v1.OnBufferedDataChangeEvent.quality_values:type_name -> mxaccess_gateway.v1.MxArray
-	91,  // 116: mxaccess_gateway.v1.OnBufferedDataChangeEvent.timestamp_values:type_name -> mxaccess_gateway.v1.MxArray
+	92,  // 115: mxaccess_gateway.v1.OnBufferedDataChangeEvent.quality_values:type_name -> mxaccess_gateway.v1.MxArray
+	92,  // 116: mxaccess_gateway.v1.OnBufferedDataChangeEvent.timestamp_values:type_name -> mxaccess_gateway.v1.MxArray
 	2,   // 117: mxaccess_gateway.v1.OnAlarmTransitionEvent.transition_kind:type_name -> mxaccess_gateway.v1.AlarmTransitionKind
-	102, // 118: mxaccess_gateway.v1.OnAlarmTransitionEvent.original_raise_timestamp:type_name -> google.protobuf.Timestamp
-	102, // 119: mxaccess_gateway.v1.OnAlarmTransitionEvent.transition_timestamp:type_name -> google.protobuf.Timestamp
-	90,  // 120: mxaccess_gateway.v1.OnAlarmTransitionEvent.current_value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 121: mxaccess_gateway.v1.OnAlarmTransitionEvent.limit_value:type_name -> mxaccess_gateway.v1.MxValue
-	102, // 122: mxaccess_gateway.v1.ActiveAlarmSnapshot.original_raise_timestamp:type_name -> google.protobuf.Timestamp
+	103, // 118: mxaccess_gateway.v1.OnAlarmTransitionEvent.original_raise_timestamp:type_name -> google.protobuf.Timestamp
+	103, // 119: mxaccess_gateway.v1.OnAlarmTransitionEvent.transition_timestamp:type_name -> google.protobuf.Timestamp
+	91,  // 120: mxaccess_gateway.v1.OnAlarmTransitionEvent.current_value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 121: mxaccess_gateway.v1.OnAlarmTransitionEvent.limit_value:type_name -> mxaccess_gateway.v1.MxValue
+	103, // 122: mxaccess_gateway.v1.ActiveAlarmSnapshot.original_raise_timestamp:type_name -> google.protobuf.Timestamp
 	3,   // 123: mxaccess_gateway.v1.ActiveAlarmSnapshot.current_state:type_name -> mxaccess_gateway.v1.AlarmConditionState
-	102, // 124: mxaccess_gateway.v1.ActiveAlarmSnapshot.last_transition_timestamp:type_name -> google.protobuf.Timestamp
-	90,  // 125: mxaccess_gateway.v1.ActiveAlarmSnapshot.current_value:type_name -> mxaccess_gateway.v1.MxValue
-	90,  // 126: mxaccess_gateway.v1.ActiveAlarmSnapshot.limit_value:type_name -> mxaccess_gateway.v1.MxValue
-	100, // 127: mxaccess_gateway.v1.AcknowledgeAlarmReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
-	89,  // 128: mxaccess_gateway.v1.AcknowledgeAlarmReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
-	4,   // 129: mxaccess_gateway.v1.MxStatusProxy.category:type_name -> mxaccess_gateway.v1.MxStatusCategory
-	5,   // 130: mxaccess_gateway.v1.MxStatusProxy.detected_by:type_name -> mxaccess_gateway.v1.MxStatusSource
-	6,   // 131: mxaccess_gateway.v1.MxValue.data_type:type_name -> mxaccess_gateway.v1.MxDataType
-	102, // 132: mxaccess_gateway.v1.MxValue.timestamp_value:type_name -> google.protobuf.Timestamp
-	91,  // 133: mxaccess_gateway.v1.MxValue.array_value:type_name -> mxaccess_gateway.v1.MxArray
-	6,   // 134: mxaccess_gateway.v1.MxArray.element_data_type:type_name -> mxaccess_gateway.v1.MxDataType
-	92,  // 135: mxaccess_gateway.v1.MxArray.bool_values:type_name -> mxaccess_gateway.v1.BoolArray
-	93,  // 136: mxaccess_gateway.v1.MxArray.int32_values:type_name -> mxaccess_gateway.v1.Int32Array
-	94,  // 137: mxaccess_gateway.v1.MxArray.int64_values:type_name -> mxaccess_gateway.v1.Int64Array
-	95,  // 138: mxaccess_gateway.v1.MxArray.float_values:type_name -> mxaccess_gateway.v1.FloatArray
-	96,  // 139: mxaccess_gateway.v1.MxArray.double_values:type_name -> mxaccess_gateway.v1.DoubleArray
-	97,  // 140: mxaccess_gateway.v1.MxArray.string_values:type_name -> mxaccess_gateway.v1.StringArray
-	98,  // 141: mxaccess_gateway.v1.MxArray.timestamp_values:type_name -> mxaccess_gateway.v1.TimestampArray
-	99,  // 142: mxaccess_gateway.v1.MxArray.raw_values:type_name -> mxaccess_gateway.v1.RawArray
-	102, // 143: mxaccess_gateway.v1.TimestampArray.values:type_name -> google.protobuf.Timestamp
-	7,   // 144: mxaccess_gateway.v1.ProtocolStatus.code:type_name -> mxaccess_gateway.v1.ProtocolStatusCode
-	9,   // 145: mxaccess_gateway.v1.MxAccessGateway.OpenSession:input_type -> mxaccess_gateway.v1.OpenSessionRequest
-	11,  // 146: mxaccess_gateway.v1.MxAccessGateway.CloseSession:input_type -> mxaccess_gateway.v1.CloseSessionRequest
-	14,  // 147: mxaccess_gateway.v1.MxAccessGateway.Invoke:input_type -> mxaccess_gateway.v1.MxCommandRequest
-	13,  // 148: mxaccess_gateway.v1.MxAccessGateway.StreamEvents:input_type -> mxaccess_gateway.v1.StreamEventsRequest
-	86,  // 149: mxaccess_gateway.v1.MxAccessGateway.AcknowledgeAlarm:input_type -> mxaccess_gateway.v1.AcknowledgeAlarmRequest
-	88,  // 150: mxaccess_gateway.v1.MxAccessGateway.QueryActiveAlarms:input_type -> mxaccess_gateway.v1.QueryActiveAlarmsRequest
-	10,  // 151: mxaccess_gateway.v1.MxAccessGateway.OpenSession:output_type -> mxaccess_gateway.v1.OpenSessionReply
-	12,  // 152: mxaccess_gateway.v1.MxAccessGateway.CloseSession:output_type -> mxaccess_gateway.v1.CloseSessionReply
-	59,  // 153: mxaccess_gateway.v1.MxAccessGateway.Invoke:output_type -> mxaccess_gateway.v1.MxCommandReply
-	79,  // 154: mxaccess_gateway.v1.MxAccessGateway.StreamEvents:output_type -> mxaccess_gateway.v1.MxEvent
-	87,  // 155: mxaccess_gateway.v1.MxAccessGateway.AcknowledgeAlarm:output_type -> mxaccess_gateway.v1.AcknowledgeAlarmReply
-	85,  // 156: mxaccess_gateway.v1.MxAccessGateway.QueryActiveAlarms:output_type -> mxaccess_gateway.v1.ActiveAlarmSnapshot
-	151, // [151:157] is the sub-list for method output_type
-	145, // [145:151] is the sub-list for method input_type
-	145, // [145:145] is the sub-list for extension type_name
-	145, // [145:145] is the sub-list for extension extendee
-	0,   // [0:145] is the sub-list for field type_name
+	103, // 124: mxaccess_gateway.v1.ActiveAlarmSnapshot.last_transition_timestamp:type_name -> google.protobuf.Timestamp
+	91,  // 125: mxaccess_gateway.v1.ActiveAlarmSnapshot.current_value:type_name -> mxaccess_gateway.v1.MxValue
+	91,  // 126: mxaccess_gateway.v1.ActiveAlarmSnapshot.limit_value:type_name -> mxaccess_gateway.v1.MxValue
+	101, // 127: mxaccess_gateway.v1.AcknowledgeAlarmReply.protocol_status:type_name -> mxaccess_gateway.v1.ProtocolStatus
+	90,  // 128: mxaccess_gateway.v1.AcknowledgeAlarmReply.status:type_name -> mxaccess_gateway.v1.MxStatusProxy
+	85,  // 129: mxaccess_gateway.v1.AlarmFeedMessage.active_alarm:type_name -> mxaccess_gateway.v1.ActiveAlarmSnapshot
+	84,  // 130: mxaccess_gateway.v1.AlarmFeedMessage.transition:type_name -> mxaccess_gateway.v1.OnAlarmTransitionEvent
+	4,   // 131: mxaccess_gateway.v1.MxStatusProxy.category:type_name -> mxaccess_gateway.v1.MxStatusCategory
+	5,   // 132: mxaccess_gateway.v1.MxStatusProxy.detected_by:type_name -> mxaccess_gateway.v1.MxStatusSource
+	6,   // 133: mxaccess_gateway.v1.MxValue.data_type:type_name -> mxaccess_gateway.v1.MxDataType
+	103, // 134: mxaccess_gateway.v1.MxValue.timestamp_value:type_name -> google.protobuf.Timestamp
+	92,  // 135: mxaccess_gateway.v1.MxValue.array_value:type_name -> mxaccess_gateway.v1.MxArray
+	6,   // 136: mxaccess_gateway.v1.MxArray.element_data_type:type_name -> mxaccess_gateway.v1.MxDataType
+	93,  // 137: mxaccess_gateway.v1.MxArray.bool_values:type_name -> mxaccess_gateway.v1.BoolArray
+	94,  // 138: mxaccess_gateway.v1.MxArray.int32_values:type_name -> mxaccess_gateway.v1.Int32Array
+	95,  // 139: mxaccess_gateway.v1.MxArray.int64_values:type_name -> mxaccess_gateway.v1.Int64Array
+	96,  // 140: mxaccess_gateway.v1.MxArray.float_values:type_name -> mxaccess_gateway.v1.FloatArray
+	97,  // 141: mxaccess_gateway.v1.MxArray.double_values:type_name -> mxaccess_gateway.v1.DoubleArray
+	98,  // 142: mxaccess_gateway.v1.MxArray.string_values:type_name -> mxaccess_gateway.v1.StringArray
+	99,  // 143: mxaccess_gateway.v1.MxArray.timestamp_values:type_name -> mxaccess_gateway.v1.TimestampArray
+	100, // 144: mxaccess_gateway.v1.MxArray.raw_values:type_name -> mxaccess_gateway.v1.RawArray
+	103, // 145: mxaccess_gateway.v1.TimestampArray.values:type_name -> google.protobuf.Timestamp
+	7,   // 146: mxaccess_gateway.v1.ProtocolStatus.code:type_name -> mxaccess_gateway.v1.ProtocolStatusCode
+	9,   // 147: mxaccess_gateway.v1.MxAccessGateway.OpenSession:input_type -> mxaccess_gateway.v1.OpenSessionRequest
+	11,  // 148: mxaccess_gateway.v1.MxAccessGateway.CloseSession:input_type -> mxaccess_gateway.v1.CloseSessionRequest
+	14,  // 149: mxaccess_gateway.v1.MxAccessGateway.Invoke:input_type -> mxaccess_gateway.v1.MxCommandRequest
+	13,  // 150: mxaccess_gateway.v1.MxAccessGateway.StreamEvents:input_type -> mxaccess_gateway.v1.StreamEventsRequest
+	86,  // 151: mxaccess_gateway.v1.MxAccessGateway.AcknowledgeAlarm:input_type -> mxaccess_gateway.v1.AcknowledgeAlarmRequest
+	88,  // 152: mxaccess_gateway.v1.MxAccessGateway.StreamAlarms:input_type -> mxaccess_gateway.v1.StreamAlarmsRequest
+	10,  // 153: mxaccess_gateway.v1.MxAccessGateway.OpenSession:output_type -> mxaccess_gateway.v1.OpenSessionReply
+	12,  // 154: mxaccess_gateway.v1.MxAccessGateway.CloseSession:output_type -> mxaccess_gateway.v1.CloseSessionReply
+	59,  // 155: mxaccess_gateway.v1.MxAccessGateway.Invoke:output_type -> mxaccess_gateway.v1.MxCommandReply
+	79,  // 156: mxaccess_gateway.v1.MxAccessGateway.StreamEvents:output_type -> mxaccess_gateway.v1.MxEvent
+	87,  // 157: mxaccess_gateway.v1.MxAccessGateway.AcknowledgeAlarm:output_type -> mxaccess_gateway.v1.AcknowledgeAlarmReply
+	89,  // 158: mxaccess_gateway.v1.MxAccessGateway.StreamAlarms:output_type -> mxaccess_gateway.v1.AlarmFeedMessage
+	153, // [153:159] is the sub-list for method output_type
+	147, // [147:153] is the sub-list for method input_type
+	147, // [147:147] is the sub-list for extension type_name
+	147, // [147:147] is the sub-list for extension extendee
+	0,   // [0:147] is the sub-list for field type_name
 }

 func init() { file_mxaccess_gateway_proto_init() }
@@ -8751,7 +8860,12 @@ func file_mxaccess_gateway_proto_init() {
 		(*MxEvent_OnAlarmTransition)(nil),
 	}
 	file_mxaccess_gateway_proto_msgTypes[78].OneofWrappers = []any{}
-	file_mxaccess_gateway_proto_msgTypes[81].OneofWrappers = []any{
+	file_mxaccess_gateway_proto_msgTypes[80].OneofWrappers = []any{
+		(*AlarmFeedMessage_ActiveAlarm)(nil),
+		(*AlarmFeedMessage_SnapshotComplete)(nil),
+		(*AlarmFeedMessage_Transition)(nil),
+	}
+	file_mxaccess_gateway_proto_msgTypes[82].OneofWrappers = []any{
 		(*MxValue_BoolValue)(nil),
 		(*MxValue_Int32Value)(nil),
 		(*MxValue_Int64Value)(nil),
@@ -8762,7 +8876,7 @@ func file_mxaccess_gateway_proto_init() {
 		(*MxValue_ArrayValue)(nil),
 		(*MxValue_RawValue)(nil),
 	}
-	file_mxaccess_gateway_proto_msgTypes[82].OneofWrappers = []any{
+	file_mxaccess_gateway_proto_msgTypes[83].OneofWrappers = []any{
 		(*MxArray_BoolValues)(nil),
 		(*MxArray_Int32Values)(nil),
 		(*MxArray_Int64Values)(nil),
@@ -8778,7 +8892,7 @@ func file_mxaccess_gateway_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: unsafe.Slice(unsafe.StringData(file_mxaccess_gateway_proto_rawDesc), len(file_mxaccess_gateway_proto_rawDesc)),
 			NumEnums:      9,
-			NumMessages:   92,
+			NumMessages:   93,
 			NumExtensions: 0,
 			NumServices:   1,
 		},
@@ -19,12 +19,12 @@ import (
 const _ = grpc.SupportPackageIsVersion9

 const (
-	MxAccessGateway_OpenSession_FullMethodName       = "/mxaccess_gateway.v1.MxAccessGateway/OpenSession"
-	MxAccessGateway_CloseSession_FullMethodName      = "/mxaccess_gateway.v1.MxAccessGateway/CloseSession"
-	MxAccessGateway_Invoke_FullMethodName            = "/mxaccess_gateway.v1.MxAccessGateway/Invoke"
-	MxAccessGateway_StreamEvents_FullMethodName      = "/mxaccess_gateway.v1.MxAccessGateway/StreamEvents"
-	MxAccessGateway_AcknowledgeAlarm_FullMethodName  = "/mxaccess_gateway.v1.MxAccessGateway/AcknowledgeAlarm"
-	MxAccessGateway_QueryActiveAlarms_FullMethodName = "/mxaccess_gateway.v1.MxAccessGateway/QueryActiveAlarms"
+	MxAccessGateway_OpenSession_FullMethodName      = "/mxaccess_gateway.v1.MxAccessGateway/OpenSession"
+	MxAccessGateway_CloseSession_FullMethodName     = "/mxaccess_gateway.v1.MxAccessGateway/CloseSession"
+	MxAccessGateway_Invoke_FullMethodName           = "/mxaccess_gateway.v1.MxAccessGateway/Invoke"
+	MxAccessGateway_StreamEvents_FullMethodName     = "/mxaccess_gateway.v1.MxAccessGateway/StreamEvents"
+	MxAccessGateway_AcknowledgeAlarm_FullMethodName = "/mxaccess_gateway.v1.MxAccessGateway/AcknowledgeAlarm"
+	MxAccessGateway_StreamAlarms_FullMethodName     = "/mxaccess_gateway.v1.MxAccessGateway/StreamAlarms"
 )

 // MxAccessGatewayClient is the client API for MxAccessGateway service.
@@ -38,7 +38,12 @@ type MxAccessGatewayClient interface {
 	Invoke(ctx context.Context, in *MxCommandRequest, opts ...grpc.CallOption) (*MxCommandReply, error)
 	StreamEvents(ctx context.Context, in *StreamEventsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[MxEvent], error)
 	AcknowledgeAlarm(ctx context.Context, in *AcknowledgeAlarmRequest, opts ...grpc.CallOption) (*AcknowledgeAlarmReply, error)
-	QueryActiveAlarms(ctx context.Context, in *QueryActiveAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[ActiveAlarmSnapshot], error)
+	// Session-less central alarm feed. The stream opens with the current
+	// active-alarm snapshot (one `active_alarm` per alarm), then a single
+	// `snapshot_complete`, then a `transition` for every subsequent change.
+	// 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)
 }

 type mxAccessGatewayClient struct {
@@ -108,13 +113,13 @@ func (c *mxAccessGatewayClient) AcknowledgeAlarm(ctx context.Context, in *Acknow
 	return out, nil
 }

-func (c *mxAccessGatewayClient) QueryActiveAlarms(ctx context.Context, in *QueryActiveAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[ActiveAlarmSnapshot], error) {
+func (c *mxAccessGatewayClient) StreamAlarms(ctx context.Context, in *StreamAlarmsRequest, opts ...grpc.CallOption) (grpc.ServerStreamingClient[AlarmFeedMessage], error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	stream, err := c.cc.NewStream(ctx, &MxAccessGateway_ServiceDesc.Streams[1], MxAccessGateway_QueryActiveAlarms_FullMethodName, cOpts...)
+	stream, err := c.cc.NewStream(ctx, &MxAccessGateway_ServiceDesc.Streams[1], MxAccessGateway_StreamAlarms_FullMethodName, cOpts...)
 	if err != nil {
 		return nil, err
 	}
-	x := &grpc.GenericClientStream[QueryActiveAlarmsRequest, ActiveAlarmSnapshot]{ClientStream: stream}
+	x := &grpc.GenericClientStream[StreamAlarmsRequest, AlarmFeedMessage]{ClientStream: stream}
 	if err := x.ClientStream.SendMsg(in); err != nil {
 		return nil, err
 	}
@@ -125,7 +130,7 @@ func (c *mxAccessGatewayClient) QueryActiveAlarms(ctx context.Context, in *Query
 }

 // 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]
+type MxAccessGateway_StreamAlarmsClient = grpc.ServerStreamingClient[AlarmFeedMessage]

 // MxAccessGatewayServer is the server API for MxAccessGateway service.
 // All implementations must embed UnimplementedMxAccessGatewayServer
@@ -138,7 +143,12 @@ type MxAccessGatewayServer interface {
 	Invoke(context.Context, *MxCommandRequest) (*MxCommandReply, error)
 	StreamEvents(*StreamEventsRequest, grpc.ServerStreamingServer[MxEvent]) error
 	AcknowledgeAlarm(context.Context, *AcknowledgeAlarmRequest) (*AcknowledgeAlarmReply, error)
-	QueryActiveAlarms(*QueryActiveAlarmsRequest, grpc.ServerStreamingServer[ActiveAlarmSnapshot]) error
+	// Session-less central alarm feed. The stream opens with the current
+	// active-alarm snapshot (one `active_alarm` per alarm), then a single
+	// `snapshot_complete`, then a `transition` for every subsequent change.
+	// 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
 	mustEmbedUnimplementedMxAccessGatewayServer()
 }

@@ -164,8 +174,8 @@ func (UnimplementedMxAccessGatewayServer) StreamEvents(*StreamEventsRequest, grp
 func (UnimplementedMxAccessGatewayServer) AcknowledgeAlarm(context.Context, *AcknowledgeAlarmRequest) (*AcknowledgeAlarmReply, error) {
 	return nil, status.Error(codes.Unimplemented, "method AcknowledgeAlarm not implemented")
 }
-func (UnimplementedMxAccessGatewayServer) QueryActiveAlarms(*QueryActiveAlarmsRequest, grpc.ServerStreamingServer[ActiveAlarmSnapshot]) error {
-	return status.Error(codes.Unimplemented, "method QueryActiveAlarms not implemented")
+func (UnimplementedMxAccessGatewayServer) StreamAlarms(*StreamAlarmsRequest, grpc.ServerStreamingServer[AlarmFeedMessage]) error {
+	return status.Error(codes.Unimplemented, "method StreamAlarms not implemented")
 }
 func (UnimplementedMxAccessGatewayServer) mustEmbedUnimplementedMxAccessGatewayServer() {}
 func (UnimplementedMxAccessGatewayServer) testEmbeddedByValue()                         {}
@@ -271,16 +281,16 @@ func _MxAccessGateway_AcknowledgeAlarm_Handler(srv interface{}, ctx context.Cont
 	return interceptor(ctx, in, info, handler)
 }

-func _MxAccessGateway_QueryActiveAlarms_Handler(srv interface{}, stream grpc.ServerStream) error {
-	m := new(QueryActiveAlarmsRequest)
+func _MxAccessGateway_StreamAlarms_Handler(srv interface{}, stream grpc.ServerStream) error {
+	m := new(StreamAlarmsRequest)
 	if err := stream.RecvMsg(m); err != nil {
 		return err
 	}
-	return srv.(MxAccessGatewayServer).QueryActiveAlarms(m, &grpc.GenericServerStream[QueryActiveAlarmsRequest, ActiveAlarmSnapshot]{ServerStream: stream})
+	return srv.(MxAccessGatewayServer).StreamAlarms(m, &grpc.GenericServerStream[StreamAlarmsRequest, AlarmFeedMessage]{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]
+type MxAccessGateway_StreamAlarmsServer = grpc.ServerStreamingServer[AlarmFeedMessage]

 // MxAccessGateway_ServiceDesc is the grpc.ServiceDesc for MxAccessGateway service.
 // It's only intended for direct use with grpc.RegisterService,
@@ -313,8 +323,8 @@ var MxAccessGateway_ServiceDesc = grpc.ServiceDesc{
 			ServerStreams: true,
 		},
 		{
-			StreamName:    "QueryActiveAlarms",
-			Handler:       _MxAccessGateway_QueryActiveAlarms_Handler,
+			StreamName:    "StreamAlarms",
+			Handler:       _MxAccessGateway_StreamAlarms_Handler,
 			ServerStreams: true,
 		},
 	},
@@ -31,22 +31,24 @@ 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.
+// 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
+// every subsequent raise / acknowledge / clear. It is served by the gateway's
+// always-on alarm monitor — no worker session is opened — so any number of
+// clients may attach.
 //
 // 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) {
+func (c *Client) StreamAlarms(ctx context.Context, req *StreamAlarmsRequest) (StreamAlarmsClient, error) {
 	if req == nil {
-		return nil, errors.New("mxgateway: query active alarms request is required")
+		return nil, errors.New("mxgateway: stream alarms request is required")
 	}

-	stream, err := c.raw.QueryActiveAlarms(ctx, req)
+	stream, err := c.raw.StreamAlarms(ctx, req)
 	if err != nil {
-		return nil, &GatewayError{Op: "query active alarms", Err: err}
+		return nil, &GatewayError{Op: "stream alarms", Err: err}
 	}

 	return stream, nil
@@ -14,13 +14,11 @@ import (
 	"google.golang.org/grpc/test/bufconn"
 )

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

 func TestAcknowledgeAlarmSendsRequestAndReturnsReply(t *testing.T) {
 	fake := &fakeGatewayWithAlarms{
 		acknowledgeReply: &pb.AcknowledgeAlarmReply{
-			SessionId:     "session-1",
 			CorrelationId: "corr-1",
 			ProtocolStatus: &pb.ProtocolStatus{
 				Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK,
@@ -35,7 +33,6 @@ func TestAcknowledgeAlarmSendsRequestAndReturnsReply(t *testing.T) {
 	defer cleanup()

 	reply, err := client.AcknowledgeAlarm(context.Background(), &pb.AcknowledgeAlarmRequest{
-		SessionId:           "session-1",
 		ClientCorrelationId: "corr-1",
 		AlarmFullReference:  "Tank01.Level.HiHi",
 		Comment:             "investigating",
@@ -77,7 +74,6 @@ func TestAcknowledgeAlarmMapsUnauthenticated(t *testing.T) {
 	defer cleanup()

 	_, err := client.AcknowledgeAlarm(context.Background(), &pb.AcknowledgeAlarmRequest{
-		SessionId:          "session-1",
 		AlarmFullReference: "Tank01.Level.HiHi",
 		OperatorUser:       "alice",
 	})
@@ -93,7 +89,7 @@ func TestAcknowledgeAlarmMapsUnauthenticated(t *testing.T) {
 	}
 }

-func TestQueryActiveAlarmsStreamsSnapshots(t *testing.T) {
+func TestStreamAlarmsStreamsSnapshotThenSnapshotComplete(t *testing.T) {
 	fake := &fakeGatewayWithAlarms{
 		activeSnapshots: []*pb.ActiveAlarmSnapshot{
 			{
@@ -111,46 +107,46 @@ func TestQueryActiveAlarmsStreamsSnapshots(t *testing.T) {
 	client, cleanup := newBufconnClientWithAlarms(t, fake)
 	defer cleanup()

-	stream, err := client.QueryActiveAlarms(context.Background(), &pb.QueryActiveAlarmsRequest{
-		SessionId: "session-1",
-	})
+	stream, err := client.StreamAlarms(context.Background(), &pb.StreamAlarmsRequest{})
 	if err != nil {
-		t.Fatalf("QueryActiveAlarms() error = %v", err)
+		t.Fatalf("StreamAlarms() error = %v", err)
 	}

-	var received []*pb.ActiveAlarmSnapshot
+	var received []*pb.AlarmFeedMessage
 	for {
-		snap, err := stream.Recv()
+		msg, err := stream.Recv()
 		if errors.Is(err, io.EOF) {
 			break
 		}
 		if err != nil {
 			t.Fatalf("stream.Recv() error = %v", err)
 		}
-		received = append(received, snap)
+		received = append(received, msg)
 	}
-	if len(received) != 2 {
-		t.Fatalf("snapshot count = %d, want 2", len(received))
+	if len(received) != 3 {
+		t.Fatalf("message count = %d, want 3", len(received))
 	}
-	if received[0].GetAlarmFullReference() != "Tank01.Level.HiHi" {
-		t.Fatalf("snapshot[0] ref = %q", received[0].GetAlarmFullReference())
+	if received[0].GetActiveAlarm().GetAlarmFullReference() != "Tank01.Level.HiHi" {
+		t.Fatalf("message[0] ref = %q", received[0].GetActiveAlarm().GetAlarmFullReference())
 	}
-	if received[1].GetCurrentState() != pb.AlarmConditionState_ALARM_CONDITION_STATE_ACTIVE_ACKED {
-		t.Fatalf("snapshot[1] state = %v", received[1].GetCurrentState())
+	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")
 	}
 }

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

-	stream, err := client.QueryActiveAlarms(context.Background(), &pb.QueryActiveAlarmsRequest{
-		SessionId:         "session-1",
+	stream, err := client.StreamAlarms(context.Background(), &pb.StreamAlarmsRequest{
 		AlarmFilterPrefix: "Tank01.",
 	})
 	if err != nil {
-		t.Fatalf("QueryActiveAlarms() error = %v", err)
+		t.Fatalf("StreamAlarms() error = %v", err)
 	}
 	for {
 		_, err := stream.Recv()
@@ -162,7 +158,7 @@ func TestQueryActiveAlarmsPassesFilterPrefix(t *testing.T) {
 		}
 	}

-	if got := fake.queryRequest.GetAlarmFilterPrefix(); got != "Tank01." {
+	if got := fake.streamRequest.GetAlarmFilterPrefix(); got != "Tank01." {
 		t.Fatalf("captured filter prefix = %q", got)
 	}
 }
@@ -175,7 +171,7 @@ type fakeGatewayWithAlarms struct {
 	acknowledgeError   error
 	acknowledgeAuth    string

-	queryRequest    *pb.QueryActiveAlarmsRequest
+	streamRequest   *pb.StreamAlarmsRequest
 	activeSnapshots []*pb.ActiveAlarmSnapshot
 }

@@ -189,21 +185,24 @@ func (s *fakeGatewayWithAlarms) AcknowledgeAlarm(ctx context.Context, req *pb.Ac
 		return s.acknowledgeReply, nil
 	}
 	return &pb.AcknowledgeAlarmReply{
-		SessionId: req.GetSessionId(),
 		ProtocolStatus: &pb.ProtocolStatus{
 			Code: pb.ProtocolStatusCode_PROTOCOL_STATUS_CODE_OK,
 		},
 	}, nil
 }

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

 func newBufconnClientWithAlarms(t *testing.T, fake *fakeGatewayWithAlarms) (*Client, func()) {
@@ -110,9 +110,12 @@ type (
 	AcknowledgeAlarmRequest = pb.AcknowledgeAlarmRequest
 	// AcknowledgeAlarmReply is the gateway AcknowledgeAlarm reply message.
 	AcknowledgeAlarmReply = pb.AcknowledgeAlarmReply
-	// QueryActiveAlarmsRequest is the gateway QueryActiveAlarms request message.
-	QueryActiveAlarmsRequest = pb.QueryActiveAlarmsRequest
-	// ActiveAlarmSnapshot is one row in a ConditionRefresh stream.
+	// 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 = pb.ActiveAlarmSnapshot
 	// OnAlarmTransitionEvent is the body carried by alarm-transition MxEvents.
 	OnAlarmTransitionEvent = pb.OnAlarmTransitionEvent
@@ -126,9 +129,9 @@ 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

 // Enumerations from the generated contract re-exported for client callers.
 type (
@@ -5,33 +5,33 @@ 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.ActiveAlarmSnapshot;
-import mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest;
+import mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage;
+import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;

 /**
- * Cancellable handle returned by {@code queryActiveAlarms}.
+ * 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 MxGatewayActiveAlarmsSubscription implements AutoCloseable {
-    private final AtomicReference<ClientCallStreamObserver<QueryActiveAlarmsRequest>> requestStream = new AtomicReference<>();
+public final class MxGatewayAlarmFeedSubscription implements AutoCloseable {
+    private final AtomicReference<ClientCallStreamObserver<StreamAlarmsRequest>> requestStream = new AtomicReference<>();
    private final AtomicBoolean cancelled = new AtomicBoolean();

-    ClientResponseObserver<QueryActiveAlarmsRequest, ActiveAlarmSnapshot> wrap(StreamObserver<ActiveAlarmSnapshot> observer) {
+    ClientResponseObserver<StreamAlarmsRequest, AlarmFeedMessage> wrap(StreamObserver<AlarmFeedMessage> observer) {
        return new ClientResponseObserver<>() {
            @Override
-            public void beforeStart(ClientCallStreamObserver<QueryActiveAlarmsRequest> stream) {
+            public void beforeStart(ClientCallStreamObserver<StreamAlarmsRequest> stream) {
                requestStream.set(stream);
                if (cancelled.get()) {
-                    stream.cancel("client cancelled active-alarms query", null);
+                    stream.cancel("client cancelled alarm feed", null);
                }
            }

            @Override
-            public void onNext(ActiveAlarmSnapshot value) {
+            public void onNext(AlarmFeedMessage value) {
                observer.onNext(value);
            }

@@ -54,9 +54,9 @@ public final class MxGatewayActiveAlarmsSubscription implements AutoCloseable {
     */
    public void cancel() {
        cancelled.set(true);
-        ClientCallStreamObserver<QueryActiveAlarmsRequest> stream = requestStream.get();
+        ClientCallStreamObserver<StreamAlarmsRequest> stream = requestStream.get();
        if (stream != null) {
-            stream.cancel("client cancelled active-alarms query", null);
+            stream.cancel("client cancelled alarm feed", null);
        }
    }

@@ -10,7 +10,7 @@ import java.util.concurrent.CompletableFuture;
 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.AlarmFeedMessage;
 import mxaccess_gateway.v1.MxaccessGateway.CloseSessionReply;
 import mxaccess_gateway.v1.MxaccessGateway.CloseSessionRequest;
 import mxaccess_gateway.v1.MxaccessGateway.MxCommandReply;
@@ -19,7 +19,7 @@ import mxaccess_gateway.v1.MxaccessGateway.MxEvent;
 import mxaccess_gateway.v1.MxaccessGateway.OpenSessionReply;
 import mxaccess_gateway.v1.MxaccessGateway.OpenSessionRequest;
 import mxaccess_gateway.v1.MxaccessGateway.ProtocolStatusCode;
-import mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest;
+import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;
 import mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest;

 /**
@@ -328,20 +328,24 @@ public final class MxGatewayClient implements AutoCloseable {
    }

    /**
-     * Streams a snapshot of all alarms currently Active or ActiveAcked — the
-     * gateway's ConditionRefresh equivalent. Used after reconnect to seed
-     * local Part 9 state.
+     * Attaches to the gateway's central alarm feed. The stream opens with one
+     * {@code AlarmFeedMessage} per currently-active alarm (the ConditionRefresh
+     * snapshot), then a single {@code snapshot_complete}, then a
+     * {@code transition} for every subsequent raise / acknowledge / clear.
     *
-     * @param request the {@code QueryActiveAlarmsRequest}, optionally scoped by
+     * <p>Served by the gateway's always-on alarm monitor — no worker session is
+     * opened — so any number of clients may attach.
+     *
+     * @param request the {@code StreamAlarmsRequest}, optionally scoped by
     *                alarm-reference prefix
-     * @param observer caller-supplied observer that receives snapshots and completion
+     * @param observer caller-supplied observer that receives feed messages and completion
     * @return a cancellable subscription handle
     */
-    public MxGatewayActiveAlarmsSubscription queryActiveAlarms(
-            QueryActiveAlarmsRequest request, StreamObserver<ActiveAlarmSnapshot> observer) {
-        MxGatewayActiveAlarmsSubscription subscription = new MxGatewayActiveAlarmsSubscription();
+    public MxGatewayAlarmFeedSubscription streamAlarms(
+            StreamAlarmsRequest request, StreamObserver<AlarmFeedMessage> observer) {
+        MxGatewayAlarmFeedSubscription subscription = new MxGatewayAlarmFeedSubscription();
        MxGatewayChannels.withStreamDeadline(rawAsyncStub(), options)
-                .queryActiveAlarms(request, subscription.wrap(observer));
+                .streamAlarms(request, subscription.wrap(observer));
        return subscription;
    }

@@ -30,10 +30,11 @@ 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.QueryActiveAlarmsRequest;
+import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;
 import mxaccess_gateway.v1.MxaccessGateway.StreamEventsRequest;
 import org.junit.jupiter.api.Test;

@@ -57,7 +58,6 @@ final class MxGatewayLowFindingsTests {
                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
                seen.set(request);
                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setSessionId(request.getSessionId())
                        .setProtocolStatus(ok())
                        .setDiagnosticMessage("acked")
                        .build());
@@ -67,7 +67,6 @@ final class MxGatewayLowFindingsTests {

        try (Harness harness = Harness.start(service, "mxgw_keyid_secret", authorization)) {
            AcknowledgeAlarmReply reply = harness.client().acknowledgeAlarm(AcknowledgeAlarmRequest.newBuilder()
-                    .setSessionId("s-1")
                    .setAlarmFullReference("Area1.Pump.PV.HiHi")
                    .setComment("operator note")
                    .build());
@@ -84,7 +83,6 @@ final class MxGatewayLowFindingsTests {
            public void acknowledgeAlarm(
                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setSessionId(request.getSessionId())
                        .setProtocolStatus(ProtocolStatus.newBuilder()
                                .setCode(ProtocolStatusCode.PROTOCOL_STATUS_CODE_SESSION_NOT_FOUND))
                        .build());
@@ -96,7 +94,7 @@ final class MxGatewayLowFindingsTests {
            assertThrows(
                    MxGatewayException.class,
                    () -> harness.client().acknowledgeAlarm(AcknowledgeAlarmRequest.newBuilder()
-                            .setSessionId("missing")
+                            .setAlarmFullReference("Area1.Pump.PV.HiHi")
                            .build()));
        }
    }
@@ -108,7 +106,6 @@ final class MxGatewayLowFindingsTests {
            public void acknowledgeAlarm(
                    AcknowledgeAlarmRequest request, StreamObserver<AcknowledgeAlarmReply> responseObserver) {
                responseObserver.onNext(AcknowledgeAlarmReply.newBuilder()
-                        .setSessionId(request.getSessionId())
                        .setProtocolStatus(ok())
                        .setDiagnosticMessage("async-acked")
                        .build());
@@ -118,7 +115,9 @@ final class MxGatewayLowFindingsTests {

        try (Harness harness = Harness.start(service)) {
            CompletableFuture<AcknowledgeAlarmReply> future = harness.client()
-                    .acknowledgeAlarmAsync(AcknowledgeAlarmRequest.newBuilder().setSessionId("s-2").build());
+                    .acknowledgeAlarmAsync(AcknowledgeAlarmRequest.newBuilder()
+                            .setAlarmFullReference("Area1.Pump.PV.HiHi")
+                            .build());
            assertEquals("async-acked", future.get(5, TimeUnit.SECONDS).getDiagnosticMessage());
        }
    }
@@ -135,39 +134,45 @@ final class MxGatewayLowFindingsTests {

        try (Harness harness = Harness.start(service)) {
            CompletableFuture<AcknowledgeAlarmReply> future = harness.client()
-                    .acknowledgeAlarmAsync(AcknowledgeAlarmRequest.newBuilder().setSessionId("s-3").build());
+                    .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: QueryActiveAlarms RPC + subscription coverage ---
+    // --- Client.Java-007: StreamAlarms RPC + subscription coverage ---

    @Test
-    void queryActiveAlarmsDeliversSnapshotsToObserver() throws Exception {
-        ActiveAlarmSnapshot snapshot = ActiveAlarmSnapshot.newBuilder()
-                .setAlarmFullReference("Area1.Tank.Level.Hi")
-                .setSeverity(800)
-                .setCurrentState(AlarmConditionState.ALARM_CONDITION_STATE_ACTIVE)
+    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 queryActiveAlarms(
-                    QueryActiveAlarmsRequest request, StreamObserver<ActiveAlarmSnapshot> responseObserver) {
-                responseObserver.onNext(snapshot);
+            public void streamAlarms(
+                    StreamAlarmsRequest request, StreamObserver<AlarmFeedMessage> responseObserver) {
+                responseObserver.onNext(active);
+                responseObserver.onNext(snapshotComplete);
                responseObserver.onCompleted();
            }
        };

        try (Harness harness = Harness.start(service)) {
-            List<ActiveAlarmSnapshot> received = new ArrayList<>();
+            List<AlarmFeedMessage> received = new ArrayList<>();
            CountDownLatch done = new CountDownLatch(1);
-            harness.client().queryActiveAlarms(
-                    QueryActiveAlarmsRequest.newBuilder().setSessionId("s-4").build(),
+            harness.client().streamAlarms(
+                    StreamAlarmsRequest.newBuilder().build(),
                    new StreamObserver<>() {
                        @Override
-                        public void onNext(ActiveAlarmSnapshot value) {
+                        public void onNext(AlarmFeedMessage value) {
                            received.add(value);
                        }

@@ -182,18 +187,19 @@ final class MxGatewayLowFindingsTests {
                        }
                    });
            assertTrue(done.await(5, TimeUnit.SECONDS), "stream should complete");
-            assertEquals(1, received.size());
-            assertEquals("Area1.Tank.Level.Hi", received.get(0).getAlarmFullReference());
+            assertEquals(2, received.size());
+            assertEquals("Area1.Tank.Level.Hi", received.get(0).getActiveAlarm().getAlarmFullReference());
+            assertTrue(received.get(1).getSnapshotComplete());
        }
    }

    @Test
-    void activeAlarmsSubscriptionCancelBeforeBeforeStartCancelsStream() {
-        MxGatewayActiveAlarmsSubscription subscription = new MxGatewayActiveAlarmsSubscription();
-        ClientResponseObserver<QueryActiveAlarmsRequest, ActiveAlarmSnapshot> observer =
+    void alarmFeedSubscriptionCancelBeforeBeforeStartCancelsStream() {
+        MxGatewayAlarmFeedSubscription subscription = new MxGatewayAlarmFeedSubscription();
+        ClientResponseObserver<StreamAlarmsRequest, AlarmFeedMessage> observer =
                subscription.wrap(new StreamObserver<>() {
                    @Override
-                    public void onNext(ActiveAlarmSnapshot value) {
+                    public void onNext(AlarmFeedMessage value) {
                    }

                    @Override
@@ -204,13 +210,13 @@ final class MxGatewayLowFindingsTests {
                    public void onCompleted() {
                    }
                });
-        RecordingActiveAlarmsRequestStream requestStream = new RecordingActiveAlarmsRequestStream();
+        RecordingAlarmFeedRequestStream requestStream = new RecordingAlarmFeedRequestStream();

        subscription.cancel();
        observer.beforeStart(requestStream);

        assertTrue(requestStream.cancelled);
-        assertEquals("client cancelled active-alarms query", requestStream.cancelMessage);
+        assertEquals("client cancelled alarm feed", requestStream.cancelMessage);
    }

    // --- Client.Java-007: async streamEvents + subscription cancellation ---
@@ -456,8 +462,8 @@ final class MxGatewayLowFindingsTests {
        }
    }

-    private static final class RecordingActiveAlarmsRequestStream
-            extends ClientCallStreamObserver<QueryActiveAlarmsRequest> {
+    private static final class RecordingAlarmFeedRequestStream
+            extends ClientCallStreamObserver<StreamAlarmsRequest> {
        private boolean cancelled;
        private String cancelMessage;

@@ -489,7 +495,7 @@ final class MxGatewayLowFindingsTests {
        }

        @Override
-        public void onNext(QueryActiveAlarmsRequest value) {
+        public void onNext(StreamAlarmsRequest value) {
        }

        @Override
@@ -170,35 +170,35 @@ public final class MxAccessGatewayGrpc {
    return getAcknowledgeAlarmMethod;
  }

-  private static volatile io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest,
-      mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> getQueryActiveAlarmsMethod;
+  private static volatile io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest,
+      mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> getStreamAlarmsMethod;

  @io.grpc.stub.annotations.RpcMethod(
-      fullMethodName = SERVICE_NAME + '/' + "QueryActiveAlarms",
-      requestType = mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest.class,
-      responseType = mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot.class,
+      fullMethodName = SERVICE_NAME + '/' + "StreamAlarms",
+      requestType = mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest.class,
+      responseType = mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage.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) {
+  public static io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest,
+      mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> getStreamAlarmsMethod() {
+    io.grpc.MethodDescriptor<mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest, mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> getStreamAlarmsMethod;
+    if ((getStreamAlarmsMethod = MxAccessGatewayGrpc.getStreamAlarmsMethod) == 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()
+        if ((getStreamAlarmsMethod = MxAccessGatewayGrpc.getStreamAlarmsMethod) == null) {
+          MxAccessGatewayGrpc.getStreamAlarmsMethod = getStreamAlarmsMethod =
+              io.grpc.MethodDescriptor.<mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest, mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>newBuilder()
              .setType(io.grpc.MethodDescriptor.MethodType.SERVER_STREAMING)
-              .setFullMethodName(generateFullMethodName(SERVICE_NAME, "QueryActiveAlarms"))
+              .setFullMethodName(generateFullMethodName(SERVICE_NAME, "StreamAlarms"))
              .setSampledToLocalTracing(true)
              .setRequestMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
-                  mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest.getDefaultInstance()))
+                  mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest.getDefaultInstance()))
              .setResponseMarshaller(io.grpc.protobuf.ProtoUtils.marshaller(
-                  mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot.getDefaultInstance()))
-              .setSchemaDescriptor(new MxAccessGatewayMethodDescriptorSupplier("QueryActiveAlarms"))
+                  mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage.getDefaultInstance()))
+              .setSchemaDescriptor(new MxAccessGatewayMethodDescriptorSupplier("StreamAlarms"))
              .build();
        }
      }
    }
-    return getQueryActiveAlarmsMethod;
+    return getStreamAlarmsMethod;
  }

  /**
@@ -303,10 +303,17 @@ public final class MxAccessGatewayGrpc {
    }

    /**
+     * <pre>
+     * Session-less central alarm feed. The stream opens with the current
+     * active-alarm snapshot (one `active_alarm` per alarm), then a single
+     * `snapshot_complete`, then a `transition` for every subsequent change.
+     * Served by the gateway's always-on alarm monitor; any number of clients
+     * fan out from the single monitor without opening a worker session.
+     * </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);
+    default void streamAlarms(mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest request,
+        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> responseObserver) {
+      io.grpc.stub.ServerCalls.asyncUnimplementedUnaryCall(getStreamAlarmsMethod(), responseObserver);
    }
  }

@@ -384,11 +391,18 @@ public final class MxAccessGatewayGrpc {
    }

    /**
+     * <pre>
+     * Session-less central alarm feed. The stream opens with the current
+     * active-alarm snapshot (one `active_alarm` per alarm), then a single
+     * `snapshot_complete`, then a `transition` for every subsequent change.
+     * Served by the gateway's always-on alarm monitor; any number of clients
+     * fan out from the single monitor without opening a worker session.
+     * </pre>
     */
-    public void queryActiveAlarms(mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request,
-        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> responseObserver) {
+    public void streamAlarms(mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest request,
+        io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> responseObserver) {
      io.grpc.stub.ClientCalls.asyncServerStreamingCall(
-          getChannel().newCall(getQueryActiveAlarmsMethod(), getCallOptions()), request, responseObserver);
+          getChannel().newCall(getStreamAlarmsMethod(), getCallOptions()), request, responseObserver);
    }
  }

@@ -449,12 +463,19 @@ public final class MxAccessGatewayGrpc {
    }

    /**
+     * <pre>
+     * Session-less central alarm feed. The stream opens with the current
+     * active-alarm snapshot (one `active_alarm` per alarm), then a single
+     * `snapshot_complete`, then a `transition` for every subsequent change.
+     * Served by the gateway's always-on alarm monitor; any number of clients
+     * fan out from the single monitor without opening a worker session.
+     * </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) {
+    public io.grpc.stub.BlockingClientCall<?, mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>
+        streamAlarms(mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest request) {
      return io.grpc.stub.ClientCalls.blockingV2ServerStreamingCall(
-          getChannel(), getQueryActiveAlarmsMethod(), getCallOptions(), request);
+          getChannel(), getStreamAlarmsMethod(), getCallOptions(), request);
    }
  }

@@ -514,11 +535,18 @@ public final class MxAccessGatewayGrpc {
    }

    /**
+     * <pre>
+     * Session-less central alarm feed. The stream opens with the current
+     * active-alarm snapshot (one `active_alarm` per alarm), then a single
+     * `snapshot_complete`, then a `transition` for every subsequent change.
+     * Served by the gateway's always-on alarm monitor; any number of clients
+     * fan out from the single monitor without opening a worker session.
+     * </pre>
     */
-    public java.util.Iterator<mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot> queryActiveAlarms(
-        mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest request) {
+    public java.util.Iterator<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage> streamAlarms(
+        mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest request) {
      return io.grpc.stub.ClientCalls.blockingServerStreamingCall(
-          getChannel(), getQueryActiveAlarmsMethod(), getCallOptions(), request);
+          getChannel(), getStreamAlarmsMethod(), getCallOptions(), request);
    }
  }

@@ -579,7 +607,7 @@ public final class MxAccessGatewayGrpc {
  private static final int METHODID_INVOKE = 2;
  private static final int METHODID_STREAM_EVENTS = 3;
  private static final int METHODID_ACKNOWLEDGE_ALARM = 4;
-  private static final int METHODID_QUERY_ACTIVE_ALARMS = 5;
+  private static final int METHODID_STREAM_ALARMS = 5;

  private static final class MethodHandlers<Req, Resp> implements
      io.grpc.stub.ServerCalls.UnaryMethod<Req, Resp>,
@@ -618,9 +646,9 @@ public final class MxAccessGatewayGrpc {
          serviceImpl.acknowledgeAlarm((mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmRequest) request,
              (io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmReply>) 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);
+        case METHODID_STREAM_ALARMS:
+          serviceImpl.streamAlarms((mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest) request,
+              (io.grpc.stub.StreamObserver<mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>) responseObserver);
          break;
        default:
          throw new AssertionError();
@@ -676,12 +704,12 @@ public final class MxAccessGatewayGrpc {
              mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmReply>(
                service, METHODID_ACKNOWLEDGE_ALARM)))
        .addMethod(
-          getQueryActiveAlarmsMethod(),
+          getStreamAlarmsMethod(),
          io.grpc.stub.ServerCalls.asyncServerStreamingCall(
            new MethodHandlers<
-              mxaccess_gateway.v1.MxaccessGateway.QueryActiveAlarmsRequest,
-              mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot>(
-                service, METHODID_QUERY_ACTIVE_ALARMS)))
+              mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest,
+              mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage>(
+                service, METHODID_STREAM_ALARMS)))
        .build();
  }

@@ -735,7 +763,7 @@ public final class MxAccessGatewayGrpc {
              .addMethod(getInvokeMethod())
              .addMethod(getStreamEventsMethod())
              .addMethod(getAcknowledgeAlarmMethod())
-              .addMethod(getQueryActiveAlarmsMethod())
+              .addMethod(getStreamAlarmsMethod())
              .build();
        }
      }
@@ -166,25 +166,27 @@ class GatewayClient:
        ensure_protocol_success("acknowledge alarm", reply.protocol_status, reply)
        return reply

-    def query_active_alarms(
+    def stream_alarms(
        self,
-        request: pb.QueryActiveAlarmsRequest,
+        request: pb.StreamAlarmsRequest,
        *,
        metadata: Sequence[tuple[str, str]] | None = None,
-    ) -> AsyncIterator[pb.ActiveAlarmSnapshot]:
-        """Stream a snapshot of all alarms currently Active or ActiveAcked.
+    ) -> AsyncIterator[pb.AlarmFeedMessage]:
+        """Attach to the gateway's central alarm feed.

-        The gateway's ConditionRefresh equivalent. Use after reconnect to seed
-        local Part 9 state, or to reconcile alarms that may have been missed
-        during a transport blip. Optionally scoped by alarm-reference prefix
-        (``request.alarm_filter_prefix``) so a partial refresh can target an
-        equipment sub-tree.
+        The stream opens with one ``AlarmFeedMessage`` per currently-active
+        alarm (the ConditionRefresh snapshot), then a single
+        ``snapshot_complete``, then a ``transition`` for every subsequent
+        raise / acknowledge / clear. Served by the gateway's always-on alarm
+        monitor — no worker session is opened — so any number of clients may
+        attach. Optionally scoped by alarm-reference prefix
+        (``request.alarm_filter_prefix``).
        """
        kwargs: dict[str, Any] = {"metadata": merge_metadata(self.options.api_key, metadata)}
        if self.options.stream_timeout is not None:
            kwargs["timeout"] = self.options.stream_timeout
-        call = _open_stream(self.raw_stub.QueryActiveAlarms, request, kwargs)
-        return _canceling_iterator(call, "query active alarms")
+        call = _open_stream(self.raw_stub.StreamAlarms, request, kwargs)
+        return _canceling_iterator(call, "stream alarms")

    async def _unary(
        self,
@@ -30,8 +30,7 @@ class MxAccessGatewayStub(object):
    additively only. Never renumber or repurpose an existing field number or
    enum value. When a field or enum value is removed, add a `reserved` range
    (and `reserved` name) covering it in the same change so a future editor
-    cannot accidentally reuse the retired tag. There are no `reserved`
-    declarations today because no field or enum value has ever been removed.
+    cannot accidentally reuse the retired tag.

    Public client API for MXAccess sessions hosted by the gateway.
    """
@@ -67,10 +66,10 @@ class MxAccessGatewayStub(object):
                request_serializer=mxaccess__gateway__pb2.AcknowledgeAlarmRequest.SerializeToString,
                response_deserializer=mxaccess__gateway__pb2.AcknowledgeAlarmReply.FromString,
                _registered_method=True)
-        self.QueryActiveAlarms = channel.unary_stream(
-                '/mxaccess_gateway.v1.MxAccessGateway/QueryActiveAlarms',
-                request_serializer=mxaccess__gateway__pb2.QueryActiveAlarmsRequest.SerializeToString,
-                response_deserializer=mxaccess__gateway__pb2.ActiveAlarmSnapshot.FromString,
+        self.StreamAlarms = channel.unary_stream(
+                '/mxaccess_gateway.v1.MxAccessGateway/StreamAlarms',
+                request_serializer=mxaccess__gateway__pb2.StreamAlarmsRequest.SerializeToString,
+                response_deserializer=mxaccess__gateway__pb2.AlarmFeedMessage.FromString,
                _registered_method=True)


@@ -79,8 +78,7 @@ class MxAccessGatewayServicer(object):
    additively only. Never renumber or repurpose an existing field number or
    enum value. When a field or enum value is removed, add a `reserved` range
    (and `reserved` name) covering it in the same change so a future editor
-    cannot accidentally reuse the retired tag. There are no `reserved`
-    declarations today because no field or enum value has ever been removed.
+    cannot accidentally reuse the retired tag.

    Public client API for MXAccess sessions hosted by the gateway.
    """
@@ -115,8 +113,13 @@ class MxAccessGatewayServicer(object):
        context.set_details('Method not implemented!')
        raise NotImplementedError('Method not implemented!')

-    def QueryActiveAlarms(self, request, context):
-        """Missing associated documentation comment in .proto file."""
+    def StreamAlarms(self, request, context):
+        """Session-less central alarm feed. The stream opens with the current
+        active-alarm snapshot (one `active_alarm` per alarm), then a single
+        `snapshot_complete`, then a `transition` for every subsequent change.
+        Served by the gateway's always-on alarm monitor; any number of clients
+        fan out from the single monitor without opening a worker session.
+        """
        context.set_code(grpc.StatusCode.UNIMPLEMENTED)
        context.set_details('Method not implemented!')
        raise NotImplementedError('Method not implemented!')
@@ -149,10 +152,10 @@ def add_MxAccessGatewayServicer_to_server(servicer, server):
                    request_deserializer=mxaccess__gateway__pb2.AcknowledgeAlarmRequest.FromString,
                    response_serializer=mxaccess__gateway__pb2.AcknowledgeAlarmReply.SerializeToString,
            ),
-            'QueryActiveAlarms': grpc.unary_stream_rpc_method_handler(
-                    servicer.QueryActiveAlarms,
-                    request_deserializer=mxaccess__gateway__pb2.QueryActiveAlarmsRequest.FromString,
-                    response_serializer=mxaccess__gateway__pb2.ActiveAlarmSnapshot.SerializeToString,
+            'StreamAlarms': grpc.unary_stream_rpc_method_handler(
+                    servicer.StreamAlarms,
+                    request_deserializer=mxaccess__gateway__pb2.StreamAlarmsRequest.FromString,
+                    response_serializer=mxaccess__gateway__pb2.AlarmFeedMessage.SerializeToString,
            ),
    }
    generic_handler = grpc.method_handlers_generic_handler(
@@ -167,8 +170,7 @@ class MxAccessGateway(object):
    additively only. Never renumber or repurpose an existing field number or
    enum value. When a field or enum value is removed, add a `reserved` range
    (and `reserved` name) covering it in the same change so a future editor
-    cannot accidentally reuse the retired tag. There are no `reserved`
-    declarations today because no field or enum value has ever been removed.
+    cannot accidentally reuse the retired tag.

    Public client API for MXAccess sessions hosted by the gateway.
    """
@@ -309,7 +311,7 @@ class MxAccessGateway(object):
            _registered_method=True)

    @staticmethod
-    def QueryActiveAlarms(request,
+    def StreamAlarms(request,
            target,
            options=(),
            channel_credentials=None,
@@ -322,9 +324,9 @@ class MxAccessGateway(object):
        return grpc.experimental.unary_stream(
            request,
            target,
-            '/mxaccess_gateway.v1.MxAccessGateway/QueryActiveAlarms',
-            mxaccess__gateway__pb2.QueryActiveAlarmsRequest.SerializeToString,
-            mxaccess__gateway__pb2.ActiveAlarmSnapshot.FromString,
+            '/mxaccess_gateway.v1.MxAccessGateway/StreamAlarms',
+            mxaccess__gateway__pb2.StreamAlarmsRequest.SerializeToString,
+            mxaccess__gateway__pb2.AlarmFeedMessage.FromString,
            options,
            channel_credentials,
            insecure,
@@ -1,8 +1,7 @@
-"""Tests for the AcknowledgeAlarm + QueryActiveAlarms client surface (PR E.3)."""
+"""Tests for the AcknowledgeAlarm + StreamAlarms client surface."""

 from __future__ import annotations

-import asyncio
 from typing import Any

 import grpc
@@ -18,7 +17,6 @@ async def test_acknowledge_alarm_sends_request_and_returns_reply() -> None:
    stub = FakeGatewayStub()
    stub.acknowledge_alarm.replies = [
        pb.AcknowledgeAlarmReply(
-            session_id="session-1",
            correlation_id="corr-7",
            protocol_status=pb.ProtocolStatus(code=pb.PROTOCOL_STATUS_CODE_OK),
            status=pb.MxStatusProxy(success=1, category=pb.MX_STATUS_CATEGORY_OK),
@@ -31,7 +29,6 @@ async def test_acknowledge_alarm_sends_request_and_returns_reply() -> None:

    reply = await client.acknowledge_alarm(
        pb.AcknowledgeAlarmRequest(
-            session_id="session-1",
            client_correlation_id="corr-7",
            alarm_full_reference="Tank01.Level.HiHi",
            comment="investigating",
@@ -61,7 +58,6 @@ async def test_acknowledge_alarm_unauthenticated_raises_typed_error() -> None:
    with pytest.raises(MxGatewayAuthenticationError):
        await client.acknowledge_alarm(
            pb.AcknowledgeAlarmRequest(
-                session_id="session-1",
                alarm_full_reference="Tank01.Level.HiHi",
                comment="",
                operator_user="alice",
@@ -81,7 +77,6 @@ async def test_acknowledge_alarm_permission_denied_raises_typed_error() -> None:
    with pytest.raises(MxGatewayAuthorizationError):
        await client.acknowledge_alarm(
            pb.AcknowledgeAlarmRequest(
-                session_id="session-1",
                alarm_full_reference="Tank01.Level.HiHi",
                comment="",
                operator_user="alice",
@@ -90,84 +85,90 @@ async def test_acknowledge_alarm_permission_denied_raises_typed_error() -> None:


@pytest.mark.asyncio
-async def test_query_active_alarms_streams_snapshots() -> None:
-    snapshots = [
-        pb.ActiveAlarmSnapshot(
-            alarm_full_reference="Tank01.Level.HiHi",
-            current_state=pb.ALARM_CONDITION_STATE_ACTIVE,
-            severity=750,
+async def test_stream_alarms_streams_snapshot_then_snapshot_complete() -> None:
+    messages = [
+        pb.AlarmFeedMessage(
+            active_alarm=pb.ActiveAlarmSnapshot(
+                alarm_full_reference="Tank01.Level.HiHi",
+                current_state=pb.ALARM_CONDITION_STATE_ACTIVE,
+                severity=750,
+            ),
        ),
-        pb.ActiveAlarmSnapshot(
-            alarm_full_reference="Tank02.Level.HiHi",
-            current_state=pb.ALARM_CONDITION_STATE_ACTIVE_ACKED,
-            severity=750,
+        pb.AlarmFeedMessage(
+            active_alarm=pb.ActiveAlarmSnapshot(
+                alarm_full_reference="Tank02.Level.HiHi",
+                current_state=pb.ALARM_CONDITION_STATE_ACTIVE_ACKED,
+                severity=750,
+            ),
        ),
+        pb.AlarmFeedMessage(snapshot_complete=True),
    ]
-    stream = FakeSnapshotStream(snapshots)
-    stub = FakeGatewayStub(snapshot_stream=stream)
+    stream = FakeAlarmFeedStream(messages)
+    stub = FakeGatewayStub(alarm_feed_stream=stream)
    client = await GatewayClient.connect(
        ClientOptions(endpoint="fake", api_key="mxgw_test_secret", plaintext=True),
        stub=stub,
    )

-    received: list[pb.ActiveAlarmSnapshot] = []
-    async for snapshot in client.query_active_alarms(
-        pb.QueryActiveAlarmsRequest(session_id="session-1"),
-    ):
-        received.append(snapshot)
+    received: list[pb.AlarmFeedMessage] = []
+    async for message in client.stream_alarms(pb.StreamAlarmsRequest()):
+        received.append(message)

-    assert len(received) == 2
-    assert received[0].alarm_full_reference == "Tank01.Level.HiHi"
-    assert received[0].current_state == pb.ALARM_CONDITION_STATE_ACTIVE
-    assert received[1].current_state == pb.ALARM_CONDITION_STATE_ACTIVE_ACKED
-    assert stub.query_metadata == (("authorization", "Bearer mxgw_test_secret"),)
+    assert len(received) == 3
+    assert received[0].active_alarm.alarm_full_reference == "Tank01.Level.HiHi"
+    assert received[0].active_alarm.current_state == pb.ALARM_CONDITION_STATE_ACTIVE
+    assert received[1].active_alarm.current_state == pb.ALARM_CONDITION_STATE_ACTIVE_ACKED
+    assert received[2].snapshot_complete is True
+    assert stub.stream_metadata == (("authorization", "Bearer mxgw_test_secret"),)


@pytest.mark.asyncio
-async def test_query_active_alarms_passes_filter_prefix() -> None:
-    stream = FakeSnapshotStream([])
-    stub = FakeGatewayStub(snapshot_stream=stream)
+async def test_stream_alarms_passes_filter_prefix() -> None:
+    stream = FakeAlarmFeedStream([])
+    stub = FakeGatewayStub(alarm_feed_stream=stream)
    client = await GatewayClient.connect(
        ClientOptions(endpoint="fake", api_key="mxgw_test_secret", plaintext=True),
        stub=stub,
    )

-    iterator = client.query_active_alarms(
-        pb.QueryActiveAlarmsRequest(session_id="session-1", alarm_filter_prefix="Tank01."),
+    iterator = client.stream_alarms(
+        pb.StreamAlarmsRequest(alarm_filter_prefix="Tank01."),
    )
    # Drain to trigger the stub call.
    async for _ in iterator:
        pass

-    assert stub.query_request is not None
-    assert stub.query_request.alarm_filter_prefix == "Tank01."
+    assert stub.stream_request is not None
+    assert stub.stream_request.alarm_filter_prefix == "Tank01."


@pytest.mark.asyncio
-async def test_query_active_alarms_cancels_underlying_stream_on_close() -> None:
-    snapshots = [
-        pb.ActiveAlarmSnapshot(
-            alarm_full_reference="Tank01.Level.HiHi",
-            current_state=pb.ALARM_CONDITION_STATE_ACTIVE,
+async def test_stream_alarms_cancels_underlying_stream_on_close() -> None:
+    messages = [
+        pb.AlarmFeedMessage(
+            active_alarm=pb.ActiveAlarmSnapshot(
+                alarm_full_reference="Tank01.Level.HiHi",
+                current_state=pb.ALARM_CONDITION_STATE_ACTIVE,
+            ),
        ),
    ]
-    stream = FakeSnapshotStream(snapshots)
-    stub = FakeGatewayStub(snapshot_stream=stream)
+    stream = FakeAlarmFeedStream(messages)
+    stub = FakeGatewayStub(alarm_feed_stream=stream)
    client = await GatewayClient.connect(
        ClientOptions(endpoint="fake", api_key="mxgw_test_secret", plaintext=True),
        stub=stub,
    )

-    iterator = client.query_active_alarms(pb.QueryActiveAlarmsRequest(session_id="session-1"))
+    iterator = client.stream_alarms(pb.StreamAlarmsRequest())
    first = await anext(iterator)
    await iterator.aclose()

-    assert first.alarm_full_reference == "Tank01.Level.HiHi"
+    assert first.active_alarm.alarm_full_reference == "Tank01.Level.HiHi"
    assert stream.cancelled


 class FakeGatewayStub:
-    def __init__(self, snapshot_stream: "FakeSnapshotStream | None" = None) -> None:
+    def __init__(self, alarm_feed_stream: "FakeAlarmFeedStream | None" = None) -> None:
        self.open_session = FakeUnary(
            [
                pb.OpenSessionReply(
@@ -179,19 +180,19 @@ class FakeGatewayStub:
        self.acknowledge_alarm = FakeUnary([])
        self.OpenSession = self.open_session
        self.AcknowledgeAlarm = self.acknowledge_alarm
-        self._snapshot_stream = snapshot_stream or FakeSnapshotStream([])
-        self.query_request: pb.QueryActiveAlarmsRequest | None = None
-        self.query_metadata: tuple[tuple[str, str], ...] | None = None
+        self._alarm_feed_stream = alarm_feed_stream or FakeAlarmFeedStream([])
+        self.stream_request: pb.StreamAlarmsRequest | None = None
+        self.stream_metadata: tuple[tuple[str, str], ...] | None = None

-    def QueryActiveAlarms(
+    def StreamAlarms(
        self,
-        request: pb.QueryActiveAlarmsRequest,
+        request: pb.StreamAlarmsRequest,
        *,
        metadata: tuple[tuple[str, str], ...],
-    ) -> "FakeSnapshotStream":
-        self.query_request = request
-        self.query_metadata = metadata
-        return self._snapshot_stream
+    ) -> "FakeAlarmFeedStream":
+        self.stream_request = request
+        self.stream_metadata = metadata
+        return self._alarm_feed_stream


 class FakeUnary:
@@ -214,18 +215,18 @@ class FakeUnary:
        return self.replies.pop(0)


-class FakeSnapshotStream:
-    def __init__(self, snapshots: list[pb.ActiveAlarmSnapshot]) -> None:
-        self._snapshots = list(snapshots)
+class FakeAlarmFeedStream:
+    def __init__(self, messages: list[pb.AlarmFeedMessage]) -> None:
+        self._messages = list(messages)
        self.cancelled = False

-    def __aiter__(self) -> "FakeSnapshotStream":
+    def __aiter__(self) -> "FakeAlarmFeedStream":
        return self

-    async def __anext__(self) -> pb.ActiveAlarmSnapshot:
-        if not self._snapshots:
+    async def __anext__(self) -> pb.AlarmFeedMessage:
+        if not self._messages:
            raise StopAsyncIteration
-        return self._snapshots.pop(0)
+        return self._messages.pop(0)

    def cancel(self) -> None:
        self.cancelled = True
@@ -1,6 +1,6 @@
 """Regression tests for Client.Python-003: stream timeout-kwarg fallback.

-`stream_events_raw` and `query_active_alarms` must tolerate a fake/older stub
+`stream_events_raw` and `stream_alarms` must tolerate a fake/older stub
 that does not accept a ``timeout`` keyword argument, matching the fallback
 already present in `galaxy.watch_deploy_events` and the unary `_unary` helper.
 """
@@ -51,9 +51,9 @@ class _NoTimeoutStubStreamEvents:
        self.StreamEvents = stream


-class _NoTimeoutStubQueryAlarms:
+class _NoTimeoutStubStreamAlarms:
    def __init__(self, stream: _NoTimeoutStream) -> None:
-        self.QueryActiveAlarms = stream
+        self.StreamAlarms = stream


@pytest.mark.asyncio
@@ -78,24 +78,30 @@ async def test_stream_events_raw_falls_back_when_stub_rejects_timeout() -> None:


@pytest.mark.asyncio
-async def test_query_active_alarms_falls_back_when_stub_rejects_timeout() -> None:
+async def test_stream_alarms_falls_back_when_stub_rejects_timeout() -> None:
    stream = _NoTimeoutStream(
-        [pb.ActiveAlarmSnapshot(alarm_full_reference="Tank01.Level.HiHi")],
+        [
+            pb.AlarmFeedMessage(
+                active_alarm=pb.ActiveAlarmSnapshot(
+                    alarm_full_reference="Tank01.Level.HiHi",
+                ),
+            ),
+        ],
    )
    client = await GatewayClient.connect(
        ClientOptions(endpoint="fake", plaintext=True, stream_timeout=5.0),
-        stub=_NoTimeoutStubQueryAlarms(stream),
+        stub=_NoTimeoutStubStreamAlarms(stream),
    )

    received = [
-        snapshot
-        async for snapshot in client.query_active_alarms(
-            pb.QueryActiveAlarmsRequest(session_id="session-1"),
+        message
+        async for message in client.stream_alarms(
+            pb.StreamAlarmsRequest(),
        )
    ]

    assert len(received) == 1
-    assert received[0].alarm_full_reference == "Tank01.Level.HiHi"
+    assert received[0].active_alarm.alarm_full_reference == "Tank01.Level.HiHi"


@pytest.mark.asyncio
@@ -16,9 +16,9 @@ use crate::auth::AuthInterceptor;
 use crate::error::{ensure_command_success, ensure_protocol_success, Error};
 use crate::generated::mxaccess_gateway::v1::mx_access_gateway_client::MxAccessGatewayClient;
 use crate::generated::mxaccess_gateway::v1::{
-    AcknowledgeAlarmReply, AcknowledgeAlarmRequest, ActiveAlarmSnapshot, CloseSessionReply,
+    AcknowledgeAlarmReply, AcknowledgeAlarmRequest, AlarmFeedMessage, CloseSessionReply,
    CloseSessionRequest, MxCommandReply, MxCommandRequest, MxEvent, OpenSessionReply,
-    OpenSessionRequest, QueryActiveAlarmsRequest, StreamEventsRequest,
+    OpenSessionRequest, StreamAlarmsRequest, StreamEventsRequest,
 };
 use crate::options::ClientOptions;
 use crate::session::Session;
@@ -33,11 +33,11 @@ pub type RawGatewayClient = MxAccessGatewayClient<InterceptedService<Channel, Au
 pub type EventStream =
    std::pin::Pin<Box<dyn futures_core::Stream<Item = Result<MxEvent, Error>> + Send + 'static>>;

-/// Pinned, boxed [`ActiveAlarmSnapshot`] stream returned by
-/// [`GatewayClient::query_active_alarms`]. Errors are pre-mapped from
+/// Pinned, boxed [`AlarmFeedMessage`] stream returned by
+/// [`GatewayClient::stream_alarms`]. Errors are pre-mapped from
 /// `tonic::Status` to [`Error`]; dropping the stream cancels the call.
-pub type ActiveAlarmStream = std::pin::Pin<
-    Box<dyn futures_core::Stream<Item = Result<ActiveAlarmSnapshot, Error>> + Send + 'static>,
+pub type AlarmFeedStream = std::pin::Pin<
+    Box<dyn futures_core::Stream<Item = Result<AlarmFeedMessage, Error>> + Send + 'static>,
 >;

 /// Thin async wrapper around the generated gateway client.
@@ -227,26 +227,27 @@ impl GatewayClient {
        Ok(reply)
    }

-    /// Open the server-streaming `QueryActiveAlarms` RPC — the gateway's
-    /// ConditionRefresh equivalent.
+    /// Attach to the gateway's central `StreamAlarms` feed.
    ///
-    /// The returned [`ActiveAlarmStream`] yields one [`ActiveAlarmSnapshot`]
-    /// per currently-active alarm. Dropping the stream cancels the gRPC call
-    /// cooperatively. Optional alarm-reference prefix scoping
-    /// (`request.alarm_filter_prefix`) limits the stream to a sub-tree.
+    /// The returned [`AlarmFeedStream`] opens with one [`AlarmFeedMessage`]
+    /// per currently-active alarm (the ConditionRefresh snapshot), then a
+    /// single `snapshot_complete`, then a `transition` for every subsequent
+    /// raise / acknowledge / clear. It is served by the gateway's always-on
+    /// alarm monitor — no worker session is opened — so any number of clients
+    /// may attach. Dropping the stream cancels the gRPC call cooperatively.
+    /// Optional alarm-reference prefix scoping (`request.alarm_filter_prefix`)
+    /// limits the stream to a sub-tree.
    ///
    /// # Errors
    ///
    /// Returns the `tonic::Status` mapped through [`Error::from`] if the
    /// server rejects the request.
-    pub async fn query_active_alarms(
+    pub async fn stream_alarms(
        &self,
-        request: QueryActiveAlarmsRequest,
-    ) -> Result<ActiveAlarmStream, Error> {
+        request: StreamAlarmsRequest,
+    ) -> Result<AlarmFeedStream, Error> {
        let mut client = self.inner.clone();
-        let response = client
-            .query_active_alarms(self.stream_request(request))
-            .await?;
+        let response = client.stream_alarms(self.stream_request(request)).await?;
        let stream = futures_util::StreamExt::map(response.into_inner(), |result| {
            result.map_err(Error::from)
        });
@@ -8,6 +8,7 @@ use std::time::Duration;

 use futures_core::Stream;
 use futures_util::StreamExt;
+use mxgateway_client::generated::mxaccess_gateway::v1::alarm_feed_message;
 use mxgateway_client::generated::mxaccess_gateway::v1::mx_access_gateway_server::{
    MxAccessGateway, MxAccessGatewayServer,
 };
@@ -16,12 +17,12 @@ use mxgateway_client::generated::mxaccess_gateway::v1::mx_command_reply;
 use mxgateway_client::generated::mxaccess_gateway::v1::mx_value::Kind;
 use mxgateway_client::generated::mxaccess_gateway::v1::{
    AcknowledgeAlarmReply, AcknowledgeAlarmRequest, ActiveAlarmSnapshot, AddItemReply,
-    BulkReadReply, BulkReadResult, BulkSubscribeReply, BulkWriteReply, BulkWriteResult,
-    CloseSessionReply, CloseSessionRequest, MxCommandKind, MxCommandReply, MxDataType, MxEvent,
-    MxEventFamily, MxStatusCategory, MxStatusProxy, MxStatusSource, MxValue, OpenSessionReply,
-    OpenSessionRequest, ProtocolStatus, ProtocolStatusCode, QueryActiveAlarmsRequest, SessionState,
-    StreamEventsRequest, SubscribeResult, Write2BulkEntry, WriteBulkEntry, WriteSecured2BulkEntry,
-    WriteSecuredBulkEntry,
+    AlarmFeedMessage, BulkReadReply, BulkReadResult, BulkSubscribeReply, BulkWriteReply,
+    BulkWriteResult, CloseSessionReply, CloseSessionRequest, MxCommandKind, MxCommandReply,
+    MxDataType, MxEvent, MxEventFamily, MxStatusCategory, MxStatusProxy, MxStatusSource, MxValue,
+    OpenSessionReply, OpenSessionRequest, ProtocolStatus, ProtocolStatusCode, SessionState,
+    StreamAlarmsRequest, StreamEventsRequest, SubscribeResult, Write2BulkEntry, WriteBulkEntry,
+    WriteSecured2BulkEntry, WriteSecuredBulkEntry,
 };
 use mxgateway_client::{
    ApiKey, ClientOptions, CommandError, Error, GatewayClient, MxStatus, MxValue as ClientMxValue,
@@ -208,7 +209,6 @@ async fn acknowledge_alarm_returns_reply_with_native_status() {

    let reply = client
        .acknowledge_alarm(AcknowledgeAlarmRequest {
-            session_id: "session-fixture".to_owned(),
            client_correlation_id: "corr-1".to_owned(),
            alarm_full_reference: "Tank01.Level.HiHi".to_owned(),
            comment: "investigating".to_owned(),
@@ -225,7 +225,7 @@ async fn acknowledge_alarm_returns_reply_with_native_status() {
 }

 #[tokio::test]
-async fn query_active_alarms_streams_snapshot_rows() {
+async fn stream_alarms_streams_snapshot_then_complete() {
    let state = Arc::new(FakeState::default());
    let endpoint = spawn_fake_gateway(state.clone()).await;
    let client = GatewayClient::connect(ClientOptions::new(endpoint))
@@ -233,15 +233,23 @@ async fn query_active_alarms_streams_snapshot_rows() {
        .unwrap();

    let mut stream = client
-        .query_active_alarms(QueryActiveAlarmsRequest {
-            session_id: "session-fixture".to_owned(),
-            ..QueryActiveAlarmsRequest::default()
-        })
+        .stream_alarms(StreamAlarmsRequest::default())
        .await
        .unwrap();

    let first = stream.next().await.unwrap().unwrap();
-    assert_eq!(first.alarm_full_reference, "Tank01.Level.HiHi");
+    match first.payload {
+        Some(alarm_feed_message::Payload::ActiveAlarm(snapshot)) => {
+            assert_eq!(snapshot.alarm_full_reference, "Tank01.Level.HiHi");
+        }
+        other => panic!("expected an active-alarm snapshot, got {other:?}"),
+    }
+
+    let second = stream.next().await.unwrap().unwrap();
+    assert_eq!(
+        second.payload,
+        Some(alarm_feed_message::Payload::SnapshotComplete(true)),
+    );
 }

 #[test]
@@ -907,7 +915,6 @@ impl MxAccessGateway for FakeGateway {
        _request: Request<AcknowledgeAlarmRequest>,
    ) -> Result<Response<AcknowledgeAlarmReply>, Status> {
        Ok(Response::new(AcknowledgeAlarmReply {
-            session_id: "session-fixture".to_owned(),
            correlation_id: "corr-1".to_owned(),
            protocol_status: Some(ok_status("ack ok")),
            status: Some(MxStatusProxy {
@@ -920,18 +927,28 @@ impl MxAccessGateway for FakeGateway {
        }))
    }

-    type QueryActiveAlarmsStream =
-        Pin<Box<dyn Stream<Item = Result<ActiveAlarmSnapshot, Status>> + Send + 'static>>;
+    type StreamAlarmsStream =
+        Pin<Box<dyn Stream<Item = Result<AlarmFeedMessage, Status>> + Send + 'static>>;

-    async fn query_active_alarms(
+    async fn stream_alarms(
        &self,
-        _request: Request<QueryActiveAlarmsRequest>,
-    ) -> Result<Response<Self::QueryActiveAlarmsStream>, Status> {
+        _request: Request<StreamAlarmsRequest>,
+    ) -> Result<Response<Self::StreamAlarmsStream>, Status> {
        let (sender, receiver) = mpsc::channel(4);
        sender
-            .send(Ok(ActiveAlarmSnapshot {
-                alarm_full_reference: "Tank01.Level.HiHi".to_owned(),
-                ..ActiveAlarmSnapshot::default()
+            .send(Ok(AlarmFeedMessage {
+                payload: Some(alarm_feed_message::Payload::ActiveAlarm(
+                    ActiveAlarmSnapshot {
+                        alarm_full_reference: "Tank01.Level.HiHi".to_owned(),
+                        ..ActiveAlarmSnapshot::default()
+                    },
+                )),
+            }))
+            .await
+            .unwrap();
+        sender
+            .send(Ok(AlarmFeedMessage {
+                payload: Some(alarm_feed_message::Payload::SnapshotComplete(true)),
            }))
            .await
            .unwrap();
@@ -1,828 +0,0 @@
-# aaAlarmManagedClient discovery — public surface, 2026-05-01
-
-Result of running
-`MxGateway.Worker.Tests.AlarmClientDiscoveryTests.DumpAlarmClientPublicSurface`
-against the deployed AVEVA assembly:
-
- File:
-  `C:\Program Files (x86)\ArchestrA\Framework\Bin\ViewAppFramework\Content\MA\aaAlarmManagedClient.dll`
- Assembly identity: `aaAlarmManagedClient, Version=1.0.7368.41290,
-  Culture=neutral, PublicKeyToken=7ebd82b507d9e10c`
-
-## Public types
-
- `aaAlarmManagedClient.AlarmClient` (class)
- `aaAlarmManagedClient.PriorityData` (class)
-
-That's the entire exported surface — two types, no interfaces, no
-delegates.
-
-## `AlarmClient` events
-
-**None.** The class has no public events at all. The reflection probe's
-`GetEvents(BindingFlags.Public | Instance | Static)` returned an empty
-list.
-
-## `AlarmClient` methods (relevant subset)
-
- **Lifecycle:**
-  `RegisterConsumer(int hWnd, string szProductName, string
-  szApplicationName, string szVersion, bool bRetainHiddenAlarms) → int`,
-  `DeregisterConsumer() → int`,
-  `InitializeConsumer(string szApplicationName) → int`,
-  `UninitializeConsumer() → int`,
-  `Dispose()`.
- **Subscription:**
-  `Subscribe(string szSubscription, short wFromPri, short wToPri,
-  eQueryType QueryType, eSortFlags SortFlags, eAlarmFilterState
-  FilterMask, eAlarmFilterState FilterSpecification) → int`.
- **Change enumeration (pull on poke):**
-  `GetStatistics(out int lPercentQuery, out int lTotalAlarms, out int
-  lActiveAlarms, out int lSuppressedAlarms, out int lSuppressedFilters,
-  out int lNewAlarms, out int lChangesCount, out int[] ChangeCodes,
-  out int[] ChangePos, out int[] hAlarm) → int`.
- **Record fetch:**
-  `GetAlarmExtendedRec(int lIndex, out AlarmRecord almRec) → int`,
-  `GetAlarmExtendedRec2(...)`,
-  `GetHighPriAlarm(out AlarmRecord almRec) → int`.
- **Selection model** (used by ack-selected-* family):
-  `DeselectAll`, `SelectAlaramEntry(short select, int from, int to)`,
-  `SelectByGUID(Guid)`, `SelectAlarmCount(int from, int to)`.
- **Acknowledge:**
-  `AlarmAckByGUID(Guid alarmGuid, string ackComment, string ackOprName,
-  string ackOprNode, string ackOprDomain, string ackOprFullName) → int`
-  is the per-alarm full-fidelity native ack.
-  `AlarmAckSelected(string ackComment, string ackOprName, string
-  ackOprNode, string ackOprDomain, string ackOprFullName) → int`
-  acks whatever the selection model currently has selected.
-  Several `AckSelected*Group/Tag/Priority/All/Visible*Alarms_Ex(...)`
-  variants exist for bulk ack scoped to a group / tag / priority range.
- **Suppress / shelve:** `SupressSelected*` and `ShelveSelected*`
-  families plus `DoAlarmShelveAction(...)`. Out of scope for the v1
-  alarm path.
- **Snapshot/filter** (`SF*` prefix): `SFSetSortA / SFSetFilterA /
-  SFCreateSnapshot / SFGetListCount / SFDeleteSnapshot / SFRefreshAlarm /
-  SFGetStatistics`. Snapshot-style query API, distinct from the
-  consumer-subscription path. Not currently used.
-
-## What this means
-
-The architecture comment on
-`src/MxGateway.Worker/MxAccess/AlarmClientConsumer.cs` (PR A.5) is
-**wrong against this deployed assembly**:
-
-> "The AVEVA alarm-manager surface (`IAlarmMgrDataProvider`) exposes
-> the events we need as plain .NET events — no Windows message pump
-> required."
-
-There is no managed event surface. `AlarmClient.RegisterConsumer`
-takes an `hWnd` because **WM_APP messaging is the actual notification
-mechanism**: AVEVA's alarm provider WM_APP-pokes the registered window,
-and the consumer is expected to call `GetStatistics` on each poke to
-pull `ChangeCodes` / `ChangePos` / `hAlarm` arrays, then
-`GetAlarmExtendedRec(pos, …)` per index to fetch each changed record.
-
-`AlarmClientConsumer.AlarmRecordReceived` has no production callers as
-a result — `RaiseAlarmRecordReceived` is `internal` for tests and
-never gets invoked at runtime. Until A.2 lands a WM_APP pump,
-`MX_EVENT_FAMILY_ON_ALARM_TRANSITION` cannot carry events.
-
-## Live runtime probe — 2026-05-01
-
-`MxGateway.Worker.Tests.AlarmClientWmProbeTests.ProbeAlarmClientWmMessages`
-is a Skip-gated runtime probe that creates a real message-only
-window, calls `AlarmClient.RegisterConsumer(hWnd, …)` +
-`Subscribe(@"\Galaxy!", …)`, and pumps for 20s while logging every
-window message that arrives. Run results below — this turned the
-"WM_APP pump" design assumption upside down.
-
-**`RegisterConsumer` and `Subscribe` both returned 0 (success).** The
-calls are valid against the deployed assembly; no parameter pinning
-needed.
-
-**A registered-message-class WM (ID `0xC275` in this OS session)
-fired every ~1s after `Subscribe` completed.** Constant
-`wParam = 0x00001100`, constant `lParam = 0x079E46D8` (looks like a
-stable pointer into AVEVA-internal state) for all 20 hits. The
-constant payload across hits with no Galaxy alarm being fired
-suggests this is a **heartbeat/keepalive**, not a per-change
-notification.
-
-**Critically: this WM is delivered to AVEVA's own internal window
-(`hwnd=0x18032E`) — NOT to the consumer's `hWnd` we passed in.** The
-consumer window's `WndProc` received only the standard creation
-sequence (`WM_GETMINMAXINFO`, `WM_NCCREATE`, `WM_NCCALCSIZE`,
-`WM_CREATE`) and the destruction sequence (`WM_NCDESTROY`,
-`WM_DESTROY`, `WM_NCCALCSIZE`) — nothing in between. AVEVA's
-notification path runs entirely against AVEVA's internal window;
-it never forwards to the user-supplied hWnd.
-
-The message ID itself is dynamic (a `RegisterWindowMessage`
-allocation in the >= 0xC000 range), so it cannot be hard-coded —
-each consumer process must call `RegisterWindowMessage` with the
-correct *string* and use whatever ID the OS returns.
-
-## What this means for A.2
-
-The "WM_APP pump on the user hWnd" design — what the original plan
-banner described and what the previous version of this doc
-recommended — does not match how AVEVA actually delivers
-notifications. The hWnd parameter to `RegisterConsumer` does not
-appear to receive any of AVEVA's alarm traffic; it's likely used
-only as a registration identity (and perhaps as a parent for modal
-dialogs).
-
-Two viable A.2 designs given the probe data:
-
-1. **Polling.** Just call `GetStatistics` on a timer (e.g. every
-   500ms in the worker's STA) and react to the change set it
-   reports. No window plumbing needed. Trade-off: latency floor =
-   poll period; modest CPU floor because the call is cheap. Matches
-   the heartbeat-style WM 0xC275 semantics — AVEVA itself runs a
-   poll loop internally.
-2. **Hook AVEVA's internal window.** Discover AVEVA's own window
-   (`hwnd=0x18032E` in the probe), `SetWindowsHookEx` or
-   `SetWindowSubclass` on it, and intercept WM 0xC275 on AVEVA's
-   thread. Higher fidelity, near-zero latency, but invasive,
-   fragile across AVEVA upgrades, and requires running on the same
-   process / thread as the AVEVA window. Probably a non-starter
-   without further AVEVA documentation.
-
-**Recommendation:** the polling path (option 1) is cheaper to
-implement, more robust against AVEVA-internal change, and
-acceptable for a typical alarm cadence. The worker's existing STA
-already provides a thread-affinitized timer surface. The unanswered
-question is whether `GetStatistics` can be safely called outside
-AVEVA's own message-pump thread — confirmable by extending the
-probe to fire `GetStatistics` on its own thread and check the
-result.
-
-## Alarm-provider visibility — third probe run, 2026-05-01
-
-Extended the probe to call `AlarmClient.GetProviders` after
-`RegisterConsumer`. Result on this rig:
-
-```
-GetProviders -> rc=0 count=0 list=[]
-```
-
-**Zero alarm providers visible to the consumer process.** This
-explains every preceding probe run: no providers means no alarm
-events, regardless of how many times any value (including a
-bool with an `$Alarm` extension) flips. `Subscribe(@"\Galaxy!")`
-returns 0 (success) but matches nothing because the alarm-manager
-chain that provides the matching feed doesn't expose any provider
-to this consumer.
-
-A System Platform script flipping `TestMachine_001.TestAlarm001`
-every 10s during this probe run produced no observable
-`GetStatistics` transitions, no `positions[]` / `handles[]`
-entries, no change in any field — confirms the silence is not
-about subscription-scope / message-pump but about provider
-absence.
-
-### Possible causes
-
-1. **No `$Alarm` extension on the test bool.** If
-   `TestMachine_001.TestAlarm001` is a regular UDA without a
-   `BoolAlarm` extension wired to it, flipping the value just
-   writes a new value — no alarm fires.
-2. **Alarm manager service not running.** AVEVA's `aaAlarmMgr`
-   (or the equivalent on this rig's Platform version) needs to
-   be running for providers to register.
-3. **Process security context.** A consumer running under a
-   normal user account may not see providers that registered
-   under `LocalSystem` / a Platform service identity. The
-   gateway-worker installation runs under a service account
-   that may have access where `dotnet test` doesn't.
-
-## InitializeConsumer required — fourth probe run, 2026-05-01
-
-Adding `InitializeConsumer("AlarmProbe.Tests")` before
-`RegisterConsumer` made `\Galaxy!` appear in `GetProviders`
-(count=1, status 0 → 100 within 500ms). So #2 and #3 above are
-NOT the cause — the consumer can see the alarm provider once it
-calls Initialize. That's a missing API-call ordering, not a
-permission or service issue.
-
-```
-InitializeConsumer -> 0
-RegisterConsumer -> 0
-GetProviders [after Register] -> rc=0 count=0 list=[]
-Subscribe('\Galaxy!') -> 0
-GetProviders [after Subscribe] -> rc=0 count=1 list=[  0 \Galaxy!]
-GetProviders [poll #1] -> rc=0 count=1 list=[100 \Galaxy!]
-```
-
-Despite the provider being visible at "100% query complete" for
-the entire 60s window, `GetStatistics` continued to report
-`total=0 active=0 codes=[7]` — no alarm transitions reached the
-consumer even with a System Platform script flipping the test
-boolean every 10s during the run.
-
-That isolates the remaining unknown to whether the test bool's
-alarm extension is actually generating MxAccess alarm-provider
-events when its value flips. The probe has confirmed every link
-in the consumer chain works (Initialize → Register → Subscribe →
-provider visible at 100%) — what's missing is alarm traffic from
-the producer side. ObjectViewer or another live consumer running
-alongside the script is the next discriminator: does it visibly
-see the alarm fire?
-
-API-ordering finding: `InitializeConsumer` MUST precede
-`RegisterConsumer` (or at least, must be called before
-`GetProviders` returns anything). PR A.5's `AlarmClientConsumer`
-omits `InitializeConsumer` entirely — that's a bug fix to apply
-even before A.2 lands, since without it the provider chain never
-becomes visible.
-
-## Subscribe-parameter sweep — fifth probe run, 2026-05-01
-
-Even with `InitializeConsumer` + provider visible at status 100,
-no alarm transitions arrived during a 60s window with the user's
-script flipping the test bool every 10s. Tried:
-
- `qtSummary` and `qtHistory` (the only `eQueryType` values).
- Priority 1..999 and 0..32767.
- `eAlarmFilterState.asNone` and `asAlarmActiveNow` for both
-  `FilterMask` and `FilterSpecification`.
-
-`eAlarmFilterState` is single-state-valued (asNone=0,
-asAlarmActiveNow=1, asAlarmAcked=2, asShelved=3), not flag bits.
-None of these knobs surfaced any alarm activity.
-
-User confirmation 2026-05-01: the test bool does have a
-`BoolAlarm` extension on it; in `aaObjectViewer` the
-`$Alarm.InAlarm` sub-attribute flips true/false in lockstep with
-the script's writes. So the alarm extension is **evaluating**
-its condition, just not visibly producing transitions on the
-`aaAlarmManagedClient` consumer stream.
-
-## Multi-channel + multi-subscription probe — sixth run, 2026-05-01
-
-Extended the probe to try every consumer-side approach in
-parallel:
-
- **Subscription expressions** (sequential): `\Galaxy!`,
-  `\Galaxy!*`, `\\Galaxy!`, `\Galaxy!TestArea`, `\\.\Galaxy!`.
-  All Subscribe calls returned rc=0; the last one
-  (`\\.\Galaxy!`) is reflected in `GetProviders` (count=1).
- **Read channels** polled at 500ms cadence: `GetStatistics`,
-  `GetHighPriAlarm`, `SFCreateSnapshot` + `SFGetStatistics`.
- **Filter+sort**: priority 0..32767, `qtSummary`,
-  state=`asAlarmActiveNow`, sort=`sfReturnNewestFirst`.
- **AlarmRecord init** (worked around `Not a valid Win32
-  FileTime` exception): all DateTime fields pre-set to FILETIME
-  epoch (1601-01-01 UTC) before the call, since
-  `default(DateTime)` is outside FILETIME range and trips the
-  interop marshaler.
-
-Result of the 60s run with `TestMachine_001.TestAlarm001` being
-flipped every 10s:
-
-```
-Subscribe('\Galaxy!') -> 0
-Subscribe('\Galaxy!*') -> 0
-Subscribe('\\Galaxy!') -> 0
-Subscribe('\Galaxy!TestArea') -> 0
-Subscribe('\\.\Galaxy!') -> 0
-GetProviders [after Subscribe-multi] -> count=1 list=[  0 \\.\Galaxy!]
-GetStatistics #1: total=0 active=0 changes=1 codes=[7] positions=[] handles=[]
-GetHighPriAlarm #1: rc=0 {  }
-SF channel #1: SFCreate=0 numAlarms=0 SFStats=0 unackRet=0 unackAlm=0 ackAlm=0 others=0 events=0 idxNewest=-1
-```
-
-**No further "(changed)" entries for the entire 60s window.**
-Every read API returned the same empty result on every poll.
-
-User confirms the alarm IS firing — `aaObjectViewer` sees
-`$Alarm.InAlarm` flip in lockstep with the script. Historian
-records exist (per user — needs verification by querying the
-historian directly).
-
-## Conclusion of consumer-side probing
-
-`aaAlarmManagedClient.AlarmClient` is **not** the receive
-surface AVEVA's alarm pipeline routes to in this Galaxy
-configuration. The consumer chain is verified end-to-end:
-
- `InitializeConsumer` + `RegisterConsumer` + `Subscribe` all
-  succeed (rc=0).
- `GetProviders` finds `\Galaxy!` once Initialize is called.
- All read APIs (`GetStatistics`, `GetHighPriAlarm`,
-  `SFCreateSnapshot`/`SFGetStatistics`) return empty even with
-  every documented filter combination.
- The consumer's hWnd receives zero AVEVA messages between
-  `WM_CREATE` and `WM_DESTROY`; AVEVA's traffic goes to its own
-  internal hwnd.
-
-The next investigation directions are not consumer-side:
-
-1. **Inspect `aaObjectViewer`'s alarm SDK** to see what library
-   it uses to read alarms. If different from
-   `aaAlarmManagedClient`, switch the worker over.
-2. **Query the historian directly** (`aahEventStorage` /
-   `aahEventSvc`) to confirm alarms are recorded — and use the
-   same path for v2 alarm capture.
-3. **Inspect AVEVA's alarm-routing config** for this Galaxy in
-   System Platform IDE — area assignments, alarm provider
-   bindings, "publish alarm events to" settings on the platform.
-
-For A.2 implementation: the `aaAlarmManagedClient` path the
-gateway-worker is currently architected around may be a
-dead-end on customer Galaxies configured this way. If the
-alarms truly only flow through the historian event-storage path,
-A.2 needs to consume from `aahEventStorage` instead — a
-fundamental architecture pivot.
-
-## BREAKTHROUGH — seventh probe run, 2026-05-01
-
-Two changes finally produced a signal:
-
-1. **Subscription scope:** `\\<MachineName>\Galaxy!<TopArea>` is the
-   canonical AlarmClient subscription format (per ArchestrA Alarm
-   Client docs at `archestra6.rssing.com/chan-12008125/article13.html`):
-   `\\Node\Provider!Area!Filter`, where Node is the *machine* name,
-   Provider is **literally `Galaxy`**, and Area is a hosted area
-   object. For this rig (`\\DESKTOP-6JL3KKO\Galaxy!DEV`) the DEV
-   area — the platform's primary area — is the right scope. Earlier
-   `\Galaxy!`, `\Galaxy!TestArea`, `\\.\Galaxy!`, etc., all returned
-   rc=0 but matched no traffic — they were not the canonical form.
-2. **`InitializeConsumer` before `RegisterConsumer`** — already
-   discovered earlier; bug-fix for PR A.5's `AlarmClientConsumer`.
-
-With both in place, `GetHighPriAlarm` returned a record on every
-poll for 60s straight (117/117 calls), but threw
-`ArgumentOutOfRangeException: Not a valid Win32 FileTime` instead
-of returning successfully — the AlarmRecord struct contains five
-DateTime fields (`ar_Time`, `ar_OrigTime`, `ar_AckTime`,
-`ar_RtnTime`, `ar_SubTime`) and AVEVA writes sentinel/invalid
-FILETIME values for unset ones (e.g., `ar_AckTime` for an
-unacknowledged alarm). The .NET interop that AVEVA ships
-(`aaAlarmManagedClient.dll`) auto-converts FILETIME→DateTime and
-rejects out-of-range values.
-
-`GetStatistics` continues to report `total=0 active=0` even with
-GetHighPriAlarm returning records — those two API surfaces have
-genuinely different views in AVEVA's data model.
-
-So: **alarms flow through `aaAlarmManagedClient.AlarmClient` once
-the subscription expression is canonical**. The blocking issue is
-extracting the payload past the .NET interop's DateTime
-auto-marshaling.
-
-## Remaining work to capture alarm payloads
-
-Define a custom COM interop that uses `long` (FILETIME-as-int64)
-instead of `DateTime` for the timestamp fields. Approach options:
-
-1. **Patch the AVEVA-shipped `aaAlarmManagedClient.dll`** — ildasm
-   the assembly, replace `DateTime` with `long` on AlarmRecord's
-   timestamp fields, ilasm back. Brittle across AVEVA upgrades.
-2. **Write our own `[ComImport]` interface** — declare
-   `IRawAlarmConsumer` ourselves with safe-blittable types,
-   discover the underlying COM IID (via reflection on
-   `AlarmClient`'s `[Guid]` attribute), and `(IRawAlarmConsumer)
-   alarmClient` cast. Cleaner; requires the IID.
-3. **Use `IDispatch` late binding** — dispatch-Invoke bypasses
-   strong-typed marshaling. Verbose but doesn't need IIDs.
-
-For PR A.2's worker integration, option 2 is the least
-disruptive. Once the interop is custom, `AlarmClient.Subscribe` +
-`GetHighPriAlarm` + `GetAlarmExtendedRec` form a viable
-polling-style alarm consumer.
-
-**REVISED 2026-05-01 — option 1 not directly applicable.**
-Reflection on `aaAlarmManagedClient.AlarmClient` shows it
-implements only `IDisposable` (no `[ComImport]` interface, no
-class GUID). It has a single field `CwwAlarmConsumer*
-m_almUnmanaged` — meaning `AlarmClient` is a **C++/CLI managed
-wrapper around a native C++ class**, NOT a COM-interop class.
-The DateTime conversion happens inside the AVEVA wrapper's IL,
-not at a .NET-to-COM marshaling boundary. There is no separate
-COM interface IID we can QI to.
-
-Revised approach options:
-
-A. **Switch to `wnwrapConsumer.dll`** — a separate standalone
-   COM library AVEVA ships at
-   `C:\Program Files (x86)\Common Files\ArchestrA\wnwrapConsumer.dll`
-   exposing `WNWRAPCONSUMERLib.wwAlarmConsumerClass` with
-   `SetXmlAlarmQuery` / `GetXmlCurrentAlarms`. XML-string output
-   bypasses FILETIME marshaling entirely.
-B. **Patch `aaAlarmManagedClient.dll` IL** — wrap the unsafe
-   `DateTime.FromFileTime` calls with a safe variant. Direct
-   fix but modifies a vendor binary.
-C. **Reflect into `m_almUnmanaged` and call native vtable** —
-   get the IntPtr, walk the MSVC C++ vtable, call
-   `__thiscall` methods via `Marshal.GetDelegateForFunctionPointer`.
-   Doable but requires reverse-engineering the C++ class layout.
-
-Option A is the best fit: real COM-based, self-contained in
-our code, conventional production-grade approach (the WIN-911
-consumer pattern referenced in AVEVA support forums uses it).
-
-The polling-vs-WM_APP-callback question from earlier is now
-moot: `GetStatistics`'s `positions[]/handles[]` arrays remained
-empty even when alarms were demonstrably present. The active
-read API for current alarms is `GetHighPriAlarm`, not
-`GetStatistics`'s change array.
-
-### Implications for A.2 implementation
-
-The A.2 PR's value is unmeasurable until at least one alarm
-provider is visible. The choice between polling-via-`GetStatistics`
-and the callback path can only be decided by observing what
-populates first when a real alarm fires. Without a provider,
-both paths return the same "nothing happening" answer.
-
-Until that's resolved, A.2 implementation work is genuinely
-blocked on a dev-rig configuration issue — not on architectural
-choice or code structure.
-
-## GetStatistics polling — second probe run, 2026-05-01
-
-Extended the probe to call `GetStatistics` every ~2s alongside the
-WM logger. Key findings:
-
- **`GetStatistics` is safely callable from the same thread that
-  did `RegisterConsumer` + `Subscribe`.** Every poll returned rc=0
-  with no exceptions over 9 polls / 20s window.
- **The deployed Galaxy currently has zero active alarms.** Every
-  poll reported `total=0 active=0 suppressed=0 newAlarms=0`. The
-  `positions[]` and `handles[]` arrays were empty.
- **`changes=1 codes=[7]` was constant across all polls**, matching
-  the constant 1 Hz WM 0xC275 cadence. Code 7 is consistent with a
-  "heartbeat / subscription healthy" sentinel — same semantics as
-  the WM but reported through the pull-side API.
- `percent=100` (query-complete percentage) was constant — the
-  subscription is steady-state.
-
-This confirms the polling design (option 1 in the previous section)
-is mechanically viable. The remaining open question is whether
-`GetStatistics` populates `positions[] / handles[]` with real
-entries when an alarm transition actually fires — proving that
-requires firing an alarm.
-
-## Open follow-up probes
-
-Each can be added to `AlarmClientWmProbeTests` as a separate
-Skip-gated test:
-
-1. **Fire a real Galaxy alarm during the pump window.** The cleanest
-   programmatic trigger is an MxAccess write that flips a
-   `$Alarm`-extended boolean to true (alarm in) and back to false
-   (alarm out). Pinning the exact tag reference is pending — needs
-   either a documented test-fixture tag or an interactive selection
-   in System Platform IDE. Once the trigger fires, this resolves
-   whether AVEVA's pulled change set arrives via `GetStatistics`
-   `positions[] / handles[]` (per-change polling works) or only via
-   the AVEVA-internal window (callback path needed).
-2. **Hook AVEVA's internal window** to log what WMs it actually
-   processes — only relevant if probe 1 shows `GetStatistics` does
-   NOT report per-change activity.
-3. **Decompile `aaAlarmManagedClient.dll`'s IL** for the
-   `RegisterConsumer` method to find what `RegisterWindowMessage`
-   string is used and whether there's a callback-registration
-   surface on `WNAL_Register` that the managed client wraps. The
-   alarmlst.dll strings (`WNAL_CallBack`, "Invalid callbacks" error)
-   suggest the underlying C API takes callbacks, but the managed
-   wrapper exposes none of them.
-
-PR A.5's `Subscribe` / `AcknowledgeByGuid` / `SnapshotActiveAlarms`
-are correct — they're pull-style and don't depend on the
-notification mechanism.
-
-## Option A — captured, 2026-05-01
-
-`wnwrapConsumer.dll` (`C:\Program Files (x86)\Common Files\
-ArchestrA\wnwrapConsumer.dll`) hosts the standalone COM class
-`WNWRAPCONSUMERLib.wwAlarmConsumerClass`. Type library imports
-cleanly via `tlbimp` (output stored under `mxaccessgw/lib/
-Interop.WNWRAPCONSUMERLib.dll`). The COM class is registered in
-`HKLM:\SOFTWARE\WOW6432Node\Classes\CLSID\
-{7AB52E5F-36B2-4A30-AE46-952A746F667C}` with `ThreadingModel=
-Apartment` — `new wwAlarmConsumerClass()` succeeds via
-`CoCreateInstance`.
-
-The probe `MxGateway.Worker.Tests/WnWrapConsumerProbeTests.cs`
-(Skip-gated, archival) drove the captured run. Lifecycle:
-
-1. `new wwAlarmConsumerClass()` — instantiated.
-2. `InitializeConsumer("MxGatewayProbe.WnWrap")` -> 0.
-3. `RegisterConsumer(hWnd: 0, productName, applicationName,
-   version)` -> 0. **Note:** wnwrap's `RegisterConsumer` is
-   4-arg (no `bRetainHiddenAlarms`); `aaAlarmManagedClient`'s
-   is 5-arg. Different surface.
-4. `Subscribe(@"\\<machine>\Galaxy!DEV", priLow=1, priHigh=999,
-   qtSummary, sfReturnNewestFirst, asAlarmActiveNow,
-   asAlarmActiveNow)` -> 0. Same canonical scope that worked
-   for `aaAlarmManagedClient`.
-5. `SetXmlAlarmQuery(...)` was called too but the round-trip
-   `GetXmlAlarmQuery` returned a mangled echo (NODE became
-   `DESKTOP-6JL3KKO\Galaxy!DEV`, PROVIDER became `Galaxy!DEV`,
-   ALARM_STATE shortened to `All`, DISPLAY_MODE truncated to
-   `Sum`). The XML-query path looks broken in this build; rely
-   on `Subscribe` for the filter and skip `SetXmlAlarmQuery` in
-   production. Confirming "Subscribe alone is sufficient" is
-   one follow-up probe (call `Subscribe` and read XML, no
-   `SetXmlAlarmQuery`) — out of scope for the breakthrough run
-   but easy to verify.
-
-### Captured XML (60 polls over 30s, 500ms cadence)
-
-`GetXmlCurrentAlarms2(maxAlmCnt: 100, out vartCurrentXmlAlarms)`
-returned BSTR XML cleanly on every call — 60/60 ok, zero throws.
-`GetXmlCurrentAlarms` (the v1 method) returned identical content
-on the same cadence; either method is viable.
-
-Empty state:
-
-```xml
-<?xml version="1.0"?><ALARM_RECORDS COUNT="0"></ALARM_RECORDS>
-```
-
-With alarm active (`UNACK_ALM`, value=true after the flip
-script set the bool true):
-
-```xml
-<?xml version="1.0"?>
-<ALARM_RECORDS COUNT="1">
-  <ALARM>
-    <GUID>BCC4705395424D65BDAABCDEA6A32A73</GUID>
-    <DATE>2026/5/1</DATE>
-    <TIME>13:26:14.709</TIME>
-    <GMTOFFSET>240</GMTOFFSET>
-    <DSTADJUST>0</DSTADJUST>
-    <PROVIDER_NODE>DESKTOP-6JL3KKO</PROVIDER_NODE>
-    <PROVIDER_NAME>Galaxy</PROVIDER_NAME>
-    <GROUP>TestArea</GROUP>
-    <TAGNAME>TestMachine_001.TestAlarm001</TAGNAME>
-    <TYPE>DSC</TYPE>
-    <VALUE>true</VALUE>
-    <LIMIT>true</LIMIT>
-    <PRIORITY>500</PRIORITY>
-    <STATE>UNACK_ALM</STATE>
-    <OPERATOR_NODE></OPERATOR_NODE>
-    <OPERATOR_NAME></OPERATOR_NAME>
-    <ALARM_COMMENT>Test alarm #1</ALARM_COMMENT>
-  </ALARM>
-</ALARM_RECORDS>
-```
-
-After the script set the bool false (`UNACK_RTN`, value=false):
-
-```xml
-<?xml version="1.0"?>
-<ALARM_RECORDS COUNT="1">
-  <ALARM>
-    <GUID>BCC4705395424D65BDAABCDEA6A32A73</GUID>
-    <DATE>2026/5/1</DATE>
-    <TIME>13:26:24.710</TIME>
-    ...
-    <VALUE>false</VALUE>
-    <STATE>UNACK_RTN</STATE>
-    ...
-  </ALARM>
-</ALARM_RECORDS>
-```
-
-The 10s cadence between transitions matches the System Platform
-script's flip frequency exactly. **GUID is stable across the
-in→out cycle** (`BCC4705…` carried through both states), so the
-XML stream represents the alarm record's lifecycle, not separate
-event records — this is "current alarms snapshot," not
-"transition stream." For an OPC UA `AlarmConditionService`
-adapter this is fine: condition-state changes per-snapshot is
-the supported model.
-
-`STATE` enum values observed: `UNACK_RTN` (the alarm has
-returned to normal but is unacknowledged — i.e., visible in the
-"current alarms" list because operator hasn't acked it yet) and
-`UNACK_ALM` (the alarm is currently active and unacknowledged).
-The other states from `eAlmState` (`ACK_RTN`, `ACK_ALM`) would
-appear when an ack is performed — `wwAlarmConsumerClass.AlarmAckByGUID`
-is the method to call.
-
-### `GetStatistics` AV — unrelated quirk
-
-Every `GetStatistics` call threw `AccessViolationException` in
-the probe. Cause: the wnwrap interop signature uses `IntPtr` for
-the three array out-parameters (`pChangeCode`, `pChangePos`,
-`phAlarm`); passing `IntPtr.Zero` is wrong — the COM impl is
-writing into the buffer pointer without null-checking. Pre-
-allocate three int-arrays and pass pinned pointers (or use
-`Marshal.AllocCoTaskMem`) to fix. Not required for the
-production path — the XML methods give us everything we need.
-
-### Implications for PR A.2 worker integration
-
-Replacing `aaAlarmManagedClient.AlarmClient` with
-`WNWRAPCONSUMERLib.wwAlarmConsumerClass` in the worker's
-alarm-consumer surface unblocks A.2 fully. Outline:
-
-1. **Reference path:** drop `aaAlarmManagedClient.dll` reference
-   from `MxGateway.Worker.csproj`; add `Interop.WNWRAPCONSUMERLib.dll`
-   reference from `mxaccessgw/lib/`. (Or commit the interop dll
-   in-tree under `lib/` and reference relatively.)
-2. **`AlarmClientConsumer` → `WnWrapAlarmConsumer`:** rewrite
-   the consumer wrapper to:
-   - `new wwAlarmConsumerClass()` on the worker's STA thread.
-   - `InitializeConsumer(applicationName)` then
-     `RegisterConsumer(hWnd: 0, …)`.
-   - `Subscribe(@"\\<node>\Galaxy!<area>", …)` per configured
-     area. The `<node>` and `<area>` are configurable (default
-     `Environment.MachineName` + the platform's primary area).
-   - Poll `GetXmlCurrentAlarms2(maxAlmCnt, out xml)` on a
-     timer (500ms-1s cadence is comfortable). Parse XML
-     payload; diff against the previous snapshot (keyed by
-     `GUID`); emit `MX_EVENT_FAMILY_ON_ALARM_TRANSITION`
-     events for added/changed/removed records.
-   - `AlarmAckByGUID(VBGUID, comment, oprName, node, domain,
-     fullName)` for client-driven acknowledgements (matches
-     PR A.5's `AlarmAckCommand` payload).
-   - Lifecycle teardown: `DeregisterConsumer` +
-     `UninitializeConsumer` + `Marshal.FinalReleaseComObject`.
-3. **Conversion layer:** map XML record fields to
-   `MxAlarmConditionRecord` proto:
-   - `GUID` → `condition_id` (canonicalize the no-dashes hex
-     to a UUID string).
-   - `STATE` enum → `inAlarm` + `acked` booleans
-     (`UNACK_ALM` → in_alarm=true, acked=false;
-     `UNACK_RTN` → in_alarm=false, acked=false;
-     `ACK_ALM` → in_alarm=true, acked=true;
-     `ACK_RTN` → in_alarm=false, acked=true).
-   - `DATE + TIME + GMTOFFSET + DSTADJUST` → reassemble UTC
-     timestamp; matches the worker's existing `Timestamp`
-     wire format.
-   - `PRIORITY` → severity (already 1-1000-ish range).
-   - `TAGNAME` → reference; `PROVIDER_NAME` + `GROUP` for
-     scope metadata.
-4. **PR A.5 fix carry-over:** `InitializeConsumer` MUST be
-   called before `RegisterConsumer` (rediscovered with
-   `aaAlarmManagedClient`, also true here). The existing
-   `AlarmClientConsumer` skips Initialize entirely; the new
-   `WnWrapAlarmConsumer` includes it from day one.
-5. **Test reuse:** PR A.5's snapshot/ack contract tests can
-   stay — they don't touch the underlying COM API. Add a new
-   integration test against the wnwrap surface (live-AVEVA-only,
-   Skip-gated like the probe).
-
-### Settled API-ordering and surface knowledge
-
- `InitializeConsumer` first, then `RegisterConsumer` — both
-  on `aaAlarmManagedClient.AlarmClient` and
-  `wwAlarmConsumerClass`.
- `RegisterConsumer` arity differs:
-  `aaAlarmManagedClient.AlarmClient.RegisterConsumer(hWnd,
-  product, app, version, bRetainHiddenAlarms)` — 5 args;
-  `wwAlarmConsumerClass.RegisterConsumer(hWnd, product, app,
-  version)` — 4 args. The wnwrap class has no
-  `bRetainHiddenAlarms` parameter at all.
- Subscription expression format: `\\<machine>\Galaxy!<area>`
-  (literal `Galaxy` provider) for both libraries.
- Native ack: `AlarmAckByGUID(VBGUID guid, comment, oprName,
-  node, domain, fullName)` on the v2 surface; ID 5-arg
-  variant on the legacy `IwwAlarmConsumer` interface.
-
-These findings retire the open follow-up probes from the
-"polling-vs-pump" debate above — `wwAlarmConsumerClass` plus
-poll-on-timer is the implementation.
-
-## Live smoke-test discoveries — 2026-05-01
-
-The Skip-gated `AlarmsLiveSmokeTests.Alarms_full_pipeline_round_trip`
-ran the full
-`WnWrapAlarmConsumer` + `AlarmDispatcher` + `MxAccessAlarmEventSink`
-pipeline against the dev rig with the flip script running. End-to-end
-verified: 6 real transitions captured on the 10s cadence, ack-by-name
-returned rc=0, pipeline stayed healthy through 5 more transitions
-afterwards. Three production-relevant quirks surfaced and were fixed
-in the consumer:
-
-### 1. `SetXmlAlarmQuery` is mandatory for reads despite the mangled echo
-
-Without `SetXmlAlarmQuery`, the first `GetXmlCurrentAlarms2` call
-fails with `E_FAIL` (HRESULT `0x80004005`). The discovery doc above
-flagged the round-trip echo as mangled and recommended skipping the
-call — that recommendation is **wrong**. The echo *is* mangled (AVEVA
-parses NODE/PROVIDER/ALARM_STATE/DISPLAY_MODE incorrectly), but the
-call itself is required as some kind of subscription enabler. Even
-the Subscribe call setting the actual filter doesn't avoid the need
-for `SetXmlAlarmQuery`.
-
-`WnWrapAlarmConsumer.ComposeXmlAlarmQuery(subscription)` decomposes
-the canonical `\\<machine>\Galaxy!<area>` form into the XML's
-NODE/PROVIDER/GROUP fields. Mangled or not, the call enables reads.
-
-### 2. Two consumers required: read-side vs. ack-side
-
-`SetXmlAlarmQuery` enables reads but **breaks `AlarmAckByName` on
-the same consumer instance**. With SetXml applied, AlarmAckByName
-returns -55 even with valid name+provider+group+operator. Without
-SetXml, AlarmAckByName succeeds with rc=0.
-
-The production consumer therefore provisions **two** wnwrap COM
-instances:
- Primary consumer (`client`): runs full lifecycle including
-  `SetXmlAlarmQuery` for `GetXmlCurrentAlarms2` polls.
- Ack-only consumer (`ackClient`): runs Initialize → Register →
-  Subscribe via the v1-prefixed methods, **no SetXmlAlarmQuery**.
-  All `AcknowledgeByName` calls dispatch through this instance.
-
-Both consumers subscribe to the same expression. Disposal cleans up
-both via a shared `ReleaseConsumerCom` helper.
-
-### 3. `AlarmAckByName` v2 8-arg vs. v1 6-arg
-
-`wwAlarmConsumerClass` exposes two `AlarmAckByName` overloads:
- `IwwAlarmConsumer2` v2: 8 args (`name, provider, group, comment,
-  oprName, node, domainName, oprFullName`).
- `IwwAlarmConsumer` v1: 6 args (no domain, no full-name).
-
-The v2 8-arg method returns -55 on this AVEVA build regardless of
-operator-identity inputs — looks like a stub. The v1 6-arg method
-works. Production `WnWrapAlarmConsumer.AcknowledgeByName` calls the
-6-arg overload and discards the proto's `domain` + `full_name` fields.
-The proto contract keeps the 8 fields for forward compatibility if
-AVEVA fixes the v2 method later.
-
-### 4. `AlarmAckByGUID` is not implemented
-
-The v2 `AlarmAckByGUID(VBGUID, …)` throws `NotImplementedException`
-(COM `E_NOTIMPL`) on `wwAlarmConsumerClass` against this AVEVA
-build. The reference→GUID lookup that we initially planned to wire
-through `AlarmAckByGUID` is therefore not viable on wnwrap; all acks
-must go through `AlarmAckByName`.
-
-The proto `AcknowledgeAlarmCommand` (GUID-based) and the worker's
-`MxAccessCommandExecutor.ExecuteAcknowledgeAlarm` switch arm remain
-in the codebase for the forward-compat shape, but the gateway-side
-`WorkerAlarmRpcDispatcher.AcknowledgeAsync` now always routes through
-`AcknowledgeAlarmByName` when the public RPC supplies a recognizable
-`Provider!Group.Tag` reference.
-
-**Command/reply payload reuse.** `MxCommand.payload` has a dedicated
-`acknowledge_alarm_by_name_command` field, but `MxCommandReply.payload`
-intentionally has **no** by-name-specific case. The by-name ack carries
-no outcome detail beyond the native return code, so the worker's
-`ExecuteAcknowledgeAlarmByName` sets the same `acknowledge_alarm`
-(`AcknowledgeAlarmReplyPayload`) reply case used by the GUID arm, with
-`native_status` = the `AlarmAckByName` return code (also echoed into the
-top-level `MxCommandReply.hresult`). Reply consumers must dispatch on
-`MxCommandReply.kind` (`MX_COMMAND_KIND_ACKNOWLEDGE_ALARM` vs.
-`MX_COMMAND_KIND_ACKNOWLEDGE_ALARM_BY_NAME`), not on the payload oneof
-case, to distinguish the two acks. `WorkerAlarmRpcDispatcher` reads only
-the top-level `hresult`/`protocol_status`, so it handles both arms
-without unpacking the payload.
-
-**Worker `native_status` → public `AcknowledgeAlarmReply` mapping.** The
-worker carries the ack outcome as a single `int32`
-(`AcknowledgeAlarmReplyPayload.native_status`, the `AlarmAckByName` /
-`AlarmAckByGUID` return code; `0` = success), also mirrored into the
-worker `MxCommandReply.hresult`. The public `AcknowledgeAlarmReply` has
-two outcome-shaped fields, but only one is populated:
-
- `AcknowledgeAlarmReply.hresult` — `WorkerAlarmRpcDispatcher` copies the
-  worker's `MxCommandReply.hresult` (the native return code) into this
-  field. **This is the authoritative ack-outcome field**; `0` means the
-  ack succeeded. It is absent only when the worker reply omitted the
-  value, which is a protocol violation surfaced in `protocol_status`.
- `AcknowledgeAlarmReply.status` (`MxStatusProxy`) — the worker by-name /
-  by-GUID ack path produces only the `int32` return code, never a
-  populated `MXSTATUS_PROXY` struct, so `WorkerAlarmRpcDispatcher` leaves
-  this field **unset on every reply**. It is reserved for a future
-  structured view of the ack outcome. Clients must not depend on it.
-
-Client authors should therefore branch on `protocol_status` first (for
-transport/session-level failures) and then on `hresult` (`0` = ack
-accepted by MXAccess) — never on `status`.
-
-### 5. STA / threading — production fix needed
-
-The wnwrap COM is `ThreadingModel=Apartment`. The consumer's
-internal `Timer` fires on threadpool threads and would block forever
-on cross-apartment marshaling unless the host STA pumps Win32
-messages. The smoke test sidesteps this by setting
-`pollIntervalMilliseconds=0` (Timer disabled) and driving `PollOnce`
-manually from the test's STA. Production hosting will route polls
-through the worker's `StaRuntime` in a follow-up — the consumer's
-`PollOnce` is `public` and idempotent so the wire-up is mechanical.
-
-### Capture summary
-
-```
-Transition: kind=Clear  ref='Galaxy!TestArea.TestMachine_001.TestAlarm001' …
-Transition: kind=Raise  ref='Galaxy!TestArea.TestMachine_001.TestAlarm001' …
-SnapshotActiveAlarms count=1
-  active: ref='Galaxy!TestArea.TestMachine_001.TestAlarm001' state=Active
-AcknowledgeByName(real identity) -> rc=0
-Post-ack transition: kind=Clear …
-+1: kind=Raise … (10s after ack)
-+2: kind=Clear … (20s)
-+3: kind=Raise … (30s)
-+4: kind=Clear … (40s)
-```
-
-10s cadence held throughout; full proto fields populated correctly;
-ack registered server-side without errors.
@@ -103,7 +103,7 @@ public string ResolveRequiredScope(object request)
        StreamEventsRequest => GatewayScopes.EventsRead,
        MxCommandRequest commandRequest => ResolveCommandScope(commandRequest.Command?.Kind ?? MxCommandKind.Unspecified),
        AcknowledgeAlarmRequest => GatewayScopes.InvokeWrite,
-        QueryActiveAlarmsRequest => GatewayScopes.EventsRead,
+        StreamAlarmsRequest => GatewayScopes.EventsRead,
        TestConnectionRequest or
        GetLastDeployTimeRequest or
        DiscoverHierarchyRequest or
@@ -113,7 +113,7 @@ public string ResolveRequiredScope(object request)
 }
 ```

-The `_ => GatewayScopes.Admin` fallback is intentional: any future request type that the resolver does not recognize fails closed, requiring the strongest scope until the resolver is updated. `AcknowledgeAlarm` is treated as a write — it mutates alarm state, mirroring `MxCommandKind.Write*` — and `QueryActiveAlarms` shares the alarm/event surface with `StreamEvents` and `MxCommandKind.DrainEvents`, so it carries `events:read`.
+The `_ => GatewayScopes.Admin` fallback is intentional: any future request type that the resolver does not recognize fails closed, requiring the strongest scope until the resolver is updated. `AcknowledgeAlarm` is treated as a write — it mutates alarm state, mirroring `MxCommandKind.Write*` — and `StreamAlarms` shares the alarm/event surface with `StreamEvents` and `MxCommandKind.DrainEvents`, so it carries `events:read`. Both alarm RPCs are session-less: the scope check is the only authorization gate, since there is no per-session ownership to enforce.

 `MxCommandRequest` is special because it multiplexes many MxAccess operations through a single RPC. The resolver inspects the embedded `MxCommandKind` so each operation gets its own scope:

@@ -205,7 +205,7 @@ blocking constraint; secured values and raw credentials are never logged.
 |----------|-------|--------------|
 | `SessionOpen` | `session:open` | `OpenSessionRequest` |
 | `SessionClose` | `session:close` | `CloseSessionRequest` |
-| `EventsRead` | `events:read` | `StreamEventsRequest`, `QueryActiveAlarmsRequest`, `MxCommandKind.DrainEvents` |
+| `EventsRead` | `events:read` | `StreamEventsRequest`, `StreamAlarmsRequest`, `MxCommandKind.DrainEvents` |
 | `InvokeRead` | `invoke:read` | `MxCommandRequest` for read-style command kinds (`Register`, `AddItem`, `Advise`, `ReadBulk`, and any kind not otherwise mapped) |
 | `InvokeWrite` | `invoke:write` | `AcknowledgeAlarmRequest`, `MxCommandKind.Write`, `MxCommandKind.Write2`, `MxCommandKind.WriteBulk`, `MxCommandKind.Write2Bulk` |
 | `InvokeSecure` | `invoke:secure` | `MxCommandKind.WriteSecured`, `MxCommandKind.WriteSecured2`, `MxCommandKind.WriteSecuredBulk`, `MxCommandKind.WriteSecured2Bulk`, `MxCommandKind.AuthenticateUser` |
@@ -61,6 +61,12 @@ paths, timeouts, queue sizes, enum values, or protocol values are invalid.
      "ConnectionString": "Server=localhost;Database=ZB;Integrated Security=True;TrustServerCertificate=True;Encrypt=False;",
      "CommandTimeoutSeconds": 60,
      "DashboardRefreshIntervalSeconds": 30
+    },
+    "Alarms": {
+      "Enabled": false,
+      "SubscriptionExpression": "",
+      "DefaultArea": "",
+      "ReconcileIntervalSeconds": 30
    }
  }
 }
@@ -168,6 +174,18 @@ at startup.
 See [Galaxy Repository Browse](./GalaxyRepository.md) for the RPC surface and
 behavior.

+## Alarm Options
+
+| Option | Default | Description |
+|--------|---------|-------------|
+| `MxGateway:Alarms:Enabled` | `false` | Gates the gateway's always-on central alarm monitor. When `true`, the gateway opens one gateway-owned worker session dedicated to alarms, caches the active-alarm set, and fans it out to every client through the `StreamAlarms` RPC — no client opens its own session to see alarms. |
+| `MxGateway:Alarms:SubscriptionExpression` | _(empty)_ | AVEVA alarm-subscription expression the monitor subscribes on startup, in canonical `\\<machine>\Galaxy!<area>` form. The literal `Galaxy` provider is correct regardless of the Galaxy database name. When empty and `Enabled` is `true`, the gateway falls back to `\\<MachineName>\Galaxy!<DefaultArea>` if `DefaultArea` is set. |
+| `MxGateway:Alarms:DefaultArea` | _(empty)_ | Area name used to compose a default subscription when `SubscriptionExpression` is empty. If both are empty while `Enabled` is `true`, the monitor faults with a configuration diagnostic. |
+| `MxGateway:Alarms:ReconcileIntervalSeconds` | `30` | How often the monitor reconciles its in-process alarm cache against the worker's authoritative active-alarm snapshot, catching transitions the live poll-and-diff feed missed. Floored at 5 seconds. |
+
+The alarm monitor is independent of client sessions: `AcknowledgeAlarm` and
+`StreamAlarms` are session-less RPCs served by the monitor.
+
 ## Related Documentation

 - [Gateway Process Detailed Design](./GatewayProcessDesign.md)
@@ -274,28 +274,32 @@ diagnostic session/worker views.

 ### Alarms page

-`/dashboard/alarms` lists the alarms the dashboard session's worker currently
-reports as Active or ActiveAcked, refreshed every three seconds. It defaults to
-showing unacknowledged `Active` alarms; filters add acknowledged alarms and
-narrow by area, severity range, and a reference/source/description text search.
-Cleared alarms are not retained — the gateway holds no alarm-history store, so
-the page reflects only the live active set. The page is read-only; it does not
-acknowledge alarms. If `MxGateway:Alarms:Enabled` is false the session is never
-subscribed to an alarm provider, and the page says so instead of showing an
-empty list with no explanation.
+`/dashboard/alarms` lists the alarms the gateway's central alarm monitor
+currently holds as Active or ActiveAcked, refreshed every three seconds. It
+defaults to showing unacknowledged `Active` alarms; filters add acknowledged
+alarms and narrow by area, severity range, and a reference/source/description
+text search. Cleared alarms are not retained — the gateway holds no
+alarm-history store, so the page reflects only the live active set. The page is
+read-only; it does not acknowledge alarms. If `MxGateway:Alarms:Enabled` is
+false the central monitor never starts, and the page says so instead of showing
+an empty list with no explanation.

 ### Live data source

 Both the Browse subscription panel and the Alarms page read live MXAccess data
-through `IDashboardLiveDataService` (`DashboardLiveDataService`). It owns one
-shared gateway session for the whole dashboard, opened lazily on first use via
-`ISessionManager` and re-opened transparently when it faults or its lease
-expires. One session means one worker process backs every dashboard circuit;
-all access is serialised so the worker sees one in-flight command at a time.
-Tag reads go through `GatewaySession.SubscribeBulkAsync` / `ReadBulkAsync`;
-alarm queries go through `IAlarmRpcDispatcher`. Alarm subscription is the
-gateway's existing auto-subscribe-on-open hook, so the dashboard session is
-alarm-subscribed only when `MxGateway:Alarms:Enabled` is set.
+through `IDashboardLiveDataService` (`DashboardLiveDataService`). For tag data
+it owns one shared gateway session for the whole dashboard, opened lazily on
+first use via `ISessionManager` and re-opened transparently when it faults or
+its lease expires. One session means one worker process backs every dashboard
+circuit; all access is serialised so the worker sees one in-flight command at a
+time. Tag reads go through `GatewaySession.SubscribeBulkAsync` / `ReadBulkAsync`.
+
+The Alarms page does **not** use the dashboard session: alarm data comes from
+the gateway's always-on central monitor. `QueryAlarmsAsync` reads
+`IGatewayAlarmService.CurrentAlarms` — the monitor's in-process cache — so the
+dashboard sees the same active-alarm set as every `StreamAlarms` client, with
+no per-dashboard alarm subscription. When `MxGateway:Alarms:Enabled` is false
+the monitor never starts and the cache stays empty.

 ### API keys page

@@ -29,7 +29,7 @@ A second gRPC service, `GalaxyRepositoryGrpcService`, is mapped alongside it. It

 ## RPC Handlers

-`MxAccessGatewayService` derives from the generated `MxAccessGateway.MxAccessGatewayBase` and implements every RPC declared in `mxaccess_gateway.proto` — six in total: `OpenSession`, `CloseSession`, `Invoke`, `StreamEvents`, `AcknowledgeAlarm`, and `QueryActiveAlarms`. The proto contract itself is documented in [Contracts](./Contracts.md); this section covers only what the server-side handler does on top of that contract.
+`MxAccessGatewayService` derives from the generated `MxAccessGateway.MxAccessGatewayBase` and implements every RPC declared in `mxaccess_gateway.proto` — six in total: `OpenSession`, `CloseSession`, `Invoke`, `StreamEvents`, `AcknowledgeAlarm`, and `StreamAlarms`. The proto contract itself is documented in [Contracts](./Contracts.md); this section covers only what the server-side handler does on top of that contract.

 Public gRPC send and receive message sizes are configured from
 `MxGateway:Protocol:MaxGrpcMessageBytes` (default 16 MiB). Official clients use
@@ -88,11 +88,11 @@ Carrying the enqueue timestamp into the worker layer is what lets queue-wait tim

 ### `AcknowledgeAlarm`

-`AcknowledgeAlarm` is a unary RPC that acknowledges a single alarm. The handler validates `session_id` and `alarm_full_reference` inline (it does not run through `MxAccessGrpcRequestValidator`, because the alarm surface routes through `IAlarmRpcDispatcher` rather than the generic `Invoke` path), resolves the session, then delegates to the registered `IAlarmRpcDispatcher`. The production `WorkerAlarmRpcDispatcher` routes the ack over the worker IPC by GUID (`AcknowledgeAlarmCommand`) when the reference parses as a canonical GUID, or by `Provider!Group.Tag` reference (`AcknowledgeAlarmByNameCommand`) otherwise. The handler-level RPC behaviour and the alarm contract itself are documented in [Alarm Client Discovery](./AlarmClientDiscovery.md).
+`AcknowledgeAlarm` is a unary, **session-less** RPC that acknowledges a single alarm. The handler validates `alarm_full_reference` inline (it does not run through `MxAccessGrpcRequestValidator`) and delegates to `IGatewayAlarmService.AcknowledgeAsync`. The always-on `GatewayAlarmMonitor` routes the ack over its own gateway-managed worker session — clients no longer open a session to acknowledge an alarm. A reference that parses as a canonical GUID forwards to `AcknowledgeAlarmCommand`; a `Provider!Group.Tag` reference forwards to `AcknowledgeAlarmByNameCommand`.

-### `QueryActiveAlarms`
+### `StreamAlarms`

-`QueryActiveAlarms` is a server-streaming RPC that returns an `ActiveAlarmSnapshot` per currently active alarm. The handler validates `session_id` inline, resolves the session, and delegates to `IAlarmRpcDispatcher`; `WorkerAlarmRpcDispatcher` issues a `QueryActiveAlarmsCommand` over the worker IPC and streams each snapshot from the worker reply.
+`StreamAlarms` is a server-streaming, **session-less** RPC that attaches to the gateway's central alarm feed. The handler delegates to `IGatewayAlarmService.StreamAsync`. The stream opens with one `AlarmFeedMessage` carrying an `active_alarm` per currently-active alarm (the ConditionRefresh snapshot), then a single `snapshot_complete`, then a `transition` for every subsequent raise / acknowledge / clear. It is served by the always-on `GatewayAlarmMonitor`, which owns a single gateway-managed worker session and fans out to every attached client — clients no longer open a session of their own. `alarm_filter_prefix`, when set, scopes the stream to a sub-tree.

 ## Validation Rules

@@ -104,8 +104,8 @@ Carrying the enqueue timestamp into the worker layer is what lets queue-wait tim
 | `CloseSession` | `session_id` must be non-empty. | `InvalidArgument` |
 | `StreamEvents` | `session_id` must be non-empty. | `InvalidArgument` |
 | `Invoke` | `session_id` non-empty, `command` present, `kind` not `Unspecified`, payload oneof must match `kind`. | `InvalidArgument` |
-| `AcknowledgeAlarm` | `session_id` and `alarm_full_reference` must be non-empty. Validated inline in the handler, not by `MxAccessGrpcRequestValidator`. | `InvalidArgument` |
-| `QueryActiveAlarms` | `session_id` must be non-empty. Validated inline in the handler, not by `MxAccessGrpcRequestValidator`. | `InvalidArgument` |
+| `AcknowledgeAlarm` | `alarm_full_reference` must be non-empty. Validated inline in the handler, not by `MxAccessGrpcRequestValidator`. | `InvalidArgument` |
+| `StreamAlarms` | No required fields — `alarm_filter_prefix` is optional. | — |

 The payload-vs-kind check matters because the `MxCommand.payload` oneof is non-discriminated on the wire — a misaligned client could send `kind = Write` with a `Register` payload and silently confuse the worker. The validator turns that into a clear client error:
Author	SHA1	Message	Date
Joseph Doherty	864b9f4bd3	Remove the AlarmClientDiscovery probe log Delete docs/AlarmClientDiscovery.md — an archival AVEVA alarm-consumer investigation log whose durable findings now live in the alarm worker/monitor code. Drop the now-dangling links from Grpc.md and GatewayConfiguration.md. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 17:04:29 -04:00
Joseph Doherty	de58872435	Document the session-less StreamAlarms feed and alarm config Update the gateway docs for the central alarm monitor reversal: Grpc.md replaces QueryActiveAlarms with the session-less StreamAlarms RPC and notes AcknowledgeAlarm no longer needs a session; Authorization.md maps StreamAlarmsRequest to events:read; GatewayConfiguration.md adds the MxGateway:Alarms options block; and GatewayDashboardDesign.md points the Alarms page at the central monitor cache instead of a per-session subscription. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 16:59:48 -04:00
Joseph Doherty	6777d49030	Point the Java client at the StreamAlarms alarm feed Regenerate the Java protobuf stubs and replace queryActiveAlarms with streamAlarms, returning a MxGatewayAlarmFeedSubscription over AlarmFeedMessage served by the gateway's central alarm monitor (snapshot, snapshot_complete, then live transitions). Drops session_id from the acknowledge surface. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 16:55:20 -04:00
Joseph Doherty	1b6ca07bb5	Point the Rust client at the StreamAlarms alarm feed Replace GatewayClient::query_active_alarms with stream_alarms, an AlarmFeedStream over AlarmFeedMessage served by the gateway's central alarm monitor (snapshot, snapshot_complete, then live transitions). Drops session_id from the acknowledge surface. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 16:49:26 -04:00
Joseph Doherty	1ad0be8276	Point the Python client at the StreamAlarms alarm feed Regenerate the Python protobuf stubs and replace query_active_alarms with stream_alarms, an AsyncIterator over AlarmFeedMessage served by the gateway's central alarm monitor (snapshot, snapshot_complete, then live transitions). Drops session_id from the acknowledge surface. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 16:45:53 -04:00
Joseph Doherty	9328c4f657	Point the Go client at the StreamAlarms alarm feed Regenerate the Go protobuf stubs and replace the session-scoped QueryActiveAlarms surface with the session-less StreamAlarms feed: snapshot-then-live AlarmFeedMessage fan-out served by the gateway's central alarm monitor. Drops session_id from the acknowledge surface. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>	2026-05-21 16:45:47 -04:00