Integration & round-trip contract suite

AGENTS.md

@@ -221,7 +221,8 @@ contract crosses layers:
 | Protobuf/API compatibility | Buf lint and breaking checks |
 | Server request semantics | `server/internal/grpcserver` tests |
 | Logical ownership and limits | `server/internal/core` lifecycle tests |
-| Unified runtime adaptation | `server` integration tests using Unified API fakes |
+| Public Universal API round trips | `test/integration` using the public client/server and hosted API spies |
+| Low-level facade and protocol integration | `server` integration tests |
 | Cancellation and cleanup | Lifecycle and integration tests |
 | Debugger commands and inspection | Core and integration debugger tests |
 | Client facade and conversions | `client` contract tests |

README.md

@@ -256,4 +256,13 @@ make test-race
 make build
 ```
 
-Tests use in-memory `bufconn` transports and direct lifecycle coverage. CI invokes these Make targets on Linux, macOS, and Windows; Linux additionally runs the race detector, Buf lint, checked generation, and pull-request breaking checks against the fetched base branch.
+The [Universal API integration suite](test/integration/README.md) exercises the
+public client/server boundary over real gRPC using an in-memory `bufconn`
+transport and hosted API spies. Run it independently with
+`go test ./test/integration/...` or `go test -race ./test/integration/...`.
+Package-local tests retain component, conversion, and low-level protocol coverage.
+
+CI invokes these Make targets on Linux, macOS, and Windows; Linux additionally
+runs the race detector, Buf lint, checked generation, and pull-request breaking
+checks against the fetched base branch. The integration suite is included in
+the existing `./...` targets without build tags or extra services.

client/remote_debug_event.go

@@ -21,11 +21,14 @@ func remoteDebuggerEvent(event wiredebugger.Event) (*debugger.Event, bool, error
 		return nil, false, snapshot.Failure
 	case wiredebugger.StateStopped:
 		result := &debugger.Event{
-			Error:            snapshot.Failure,
 			Reason:           snapshot.StopReason,
 			HitBreakpointIDs: append([]debugger.BreakpointID(nil), snapshot.HitBreakpointIDs...),
 			Depth:            snapshot.Depth,
 		}
+		if snapshot.Failure != nil {
+			result.Error = snapshot.Failure
+		}
+
 		if snapshot.Location != nil {
 			result.Location = *snapshot.Location
 		}