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clients/go/mxgateway/errors.go

@@ -8,10 +8,13 @@ import (
 
 // GatewayError wraps transport-level gRPC failures.
 type GatewayError struct {
-	Op  string
+	// Op names the operation that failed (for example "dial" or "invoke").
+	Op string
+	// Err is the underlying gRPC or transport error.
 	Err error
 }
 
+// Error returns the formatted gateway error message.
 func (e *GatewayError) Error() string {
 	if e == nil {
 		return ""
@@ -22,6 +25,7 @@ func (e *GatewayError) Error() string {
 	return fmt.Sprintf("mxgateway: %s failed: %v", e.Op, e.Err)
 }
 
+// Unwrap returns the wrapped transport error.
 func (e *GatewayError) Unwrap() error {
 	if e == nil {
 		return nil
@@ -32,11 +36,15 @@ func (e *GatewayError) Unwrap() error {
 // CommandError reports a non-OK gateway protocol status and keeps the raw
 // command reply when one exists.
 type CommandError struct {
-	Op     string
+	// Op names the gateway operation that produced the non-OK status.
+	Op string
+	// Status carries the gateway-reported protocol status.
 	Status *ProtocolStatus
-	Reply  *MxCommandReply
+	// Reply is the raw command reply, when one was returned alongside the status.
+	Reply *MxCommandReply
 }
 
+// Error returns the formatted command error message.
 func (e *CommandError) Error() string {
 	if e == nil {
 		return ""
@@ -53,10 +61,13 @@ func (e *CommandError) Error() string {
 
 // MxAccessError reports HRESULT or MXSTATUS_PROXY failures returned by MXAccess.
 type MxAccessError struct {
+	// Command is the wrapped CommandError when the protocol status carried one.
 	Command *CommandError
-	Reply   *MxCommandReply
+	// Reply is the raw MXAccess command reply that surfaced the failure.
+	Reply *MxCommandReply
 }
 
+// Error returns the formatted MXAccess error message.
 func (e *MxAccessError) Error() string {
 	if e == nil {
 		return ""
@@ -73,6 +84,7 @@ func (e *MxAccessError) Error() string {
 	return "mxgateway: MXAccess command failed"
 }
 
+// Unwrap returns the wrapped CommandError, when one is present.
 func (e *MxAccessError) Unwrap() error {
 	if e == nil {
 		return nil