ManageGameObject/Material + auto-select sole Unity instance (#502)

- ManageGameObject: support componentsToAdd string array + apply top-level componentProperties

- ManageMaterial: safer create + optional color input with configurable property

- Server: auto-select sole Unity instance middleware + integration tests

MCPForUnity/Editor/Tools/ManageGameObject.cs

@@ -1450,7 +1450,11 @@ namespace MCPForUnity.Editor.Tools
             {
                 var compToken = componentsToAddArray.First;
                 if (compToken.Type == JTokenType.String)
+                {
                     typeName = compToken.ToString();
+                    // Check for properties in top-level componentProperties parameter
+                    properties = @params["componentProperties"]?[typeName] as JObject;
+                }
                 else if (compToken is JObject compObj)
                 {
                     typeName = compObj["typeName"]?.ToString();

MCPForUnity/Editor/Tools/ManageMaterial.cs

@@ -460,6 +460,8 @@ namespace MCPForUnity.Editor.Tools
         {
             string materialPath = NormalizePath(@params["materialPath"]?.ToString());
             string shaderName = @params["shader"]?.ToString() ?? "Standard";
+            JToken colorToken = @params["color"];
+            string colorProperty = @params["property"]?.ToString();
             
             JObject properties = null;
             JToken propsToken = @params["properties"];
@@ -494,15 +496,86 @@ namespace MCPForUnity.Editor.Tools
                 return new { status = "error", message = $"Could not find shader: {shaderName}" };
             }
 
-            Material material = new Material(shader);
-            
             // Check for existing asset to avoid silent overwrite
             if (AssetDatabase.LoadAssetAtPath<Material>(materialPath) != null)
             {
                 return new { status = "error", message = $"Material already exists at {materialPath}" };
             }
 
+            Material material = null;
+            var shouldDestroyMaterial = true;
+            try
+            {
+                material = new Material(shader);
+
+                // Apply color param during creation (keeps Python tool signature and C# implementation consistent).
+                // If "properties" already contains a color property, let properties win.
+                bool shouldApplyColor = false;
+                if (colorToken != null)
+                {
+                    if (properties == null)
+                    {
+                        shouldApplyColor = true;
+                    }
+                    else if (!string.IsNullOrEmpty(colorProperty))
+                    {
+                        // If colorProperty is specified, only check that specific property.
+                        shouldApplyColor = !properties.ContainsKey(colorProperty);
+                    }
+                    else
+                    {
+                        // If colorProperty is not specified, check fallback properties.
+                        shouldApplyColor = !properties.ContainsKey("_BaseColor") && !properties.ContainsKey("_Color");
+                    }
+                }
+
+                if (shouldApplyColor)
+                {
+                    Color color;
+                    try
+                    {
+                        color = MaterialOps.ParseColor(colorToken, ManageGameObject.InputSerializer);
+                    }
+                    catch (Exception e)
+                    {
+                        return new { status = "error", message = $"Invalid color format: {e.Message}" };
+                    }
+
+                    if (!string.IsNullOrEmpty(colorProperty))
+                    {
+                        if (material.HasProperty(colorProperty))
+                        {
+                            material.SetColor(colorProperty, color);
+                        }
+                        else
+                        {
+                            return new
+                            {
+                                status = "error",
+                                message = $"Specified color property '{colorProperty}' does not exist on this material."
+                            };
+                        }
+                    }
+                    else if (material.HasProperty("_BaseColor"))
+                    {
+                        material.SetColor("_BaseColor", color);
+                    }
+                    else if (material.HasProperty("_Color"))
+                    {
+                        material.SetColor("_Color", color);
+                    }
+                    else
+                    {
+                        return new
+                        {
+                            status = "error",
+                            message = "Could not find suitable color property (_BaseColor or _Color) on this material's shader."
+                        };
+                    }
+                }
+
                 AssetDatabase.CreateAsset(material, materialPath);
+                shouldDestroyMaterial = false; // material is now owned by the AssetDatabase
 
                 if (properties != null)
                 {
@@ -514,5 +587,13 @@ namespace MCPForUnity.Editor.Tools
 
                 return new { status = "success", message = $"Created material at {materialPath} with shader {shaderName}" };
             }
+            finally
+            {
+                if (shouldDestroyMaterial && material != null)
+                {
+                    UnityEngine.Object.DestroyImmediate(material);
+                }
+            }
+        }
     }
 }

Server/src/transport/unity_instance_middleware.py

@@ -83,11 +83,101 @@ class UnityInstanceMiddleware(Middleware):
         with self._lock:
             self._active_by_key.pop(key, None)
 
+    async def _maybe_autoselect_instance(self, ctx) -> str | None:
+        """
+        Auto-select the sole Unity instance when no active instance is set.
+
+        Note: This method both *discovers* and *persists* the selection via
+        `set_active_instance` as a side-effect, since callers expect the selection
+        to stick for subsequent tool/resource calls in the same session.
+        """
+        try:
+            # Import here to avoid circular dependencies / optional transport modules.
+            from transport.unity_transport import _current_transport
+
+            transport = _current_transport()
+            if PluginHub.is_configured():
+                try:
+                    sessions_data = await PluginHub.get_sessions()
+                    sessions = sessions_data.sessions or {}
+                    ids: list[str] = []
+                    for session_info in sessions.values():
+                        project = getattr(session_info, "project", None) or "Unknown"
+                        hash_value = getattr(session_info, "hash", None)
+                        if hash_value:
+                            ids.append(f"{project}@{hash_value}")
+                    if len(ids) == 1:
+                        chosen = ids[0]
+                        self.set_active_instance(ctx, chosen)
+                        logger.info(
+                            "Auto-selected sole Unity instance via PluginHub: %s",
+                            chosen,
+                        )
+                        return chosen
+                except (ConnectionError, ValueError, KeyError, TimeoutError, AttributeError) as exc:
+                    logger.debug(
+                        "PluginHub auto-select probe failed (%s); falling back to stdio",
+                        type(exc).__name__,
+                        exc_info=True,
+                    )
+                except Exception as exc:
+                    if isinstance(exc, (SystemExit, KeyboardInterrupt)):
+                        raise
+                    logger.debug(
+                        "PluginHub auto-select probe failed with unexpected error (%s); falling back to stdio",
+                        type(exc).__name__,
+                        exc_info=True,
+                    )
+
+            if transport != "http":
+                try:
+                    # Import here to avoid circular imports in legacy transport paths.
+                    from transport.legacy.unity_connection import get_unity_connection_pool
+
+                    pool = get_unity_connection_pool()
+                    instances = pool.discover_all_instances(force_refresh=True)
+                    ids = [getattr(inst, "id", None) for inst in instances]
+                    ids = [inst_id for inst_id in ids if inst_id]
+                    if len(ids) == 1:
+                        chosen = ids[0]
+                        self.set_active_instance(ctx, chosen)
+                        logger.info(
+                            "Auto-selected sole Unity instance via stdio discovery: %s",
+                            chosen,
+                        )
+                        return chosen
+                except (ConnectionError, ValueError, KeyError, TimeoutError, AttributeError) as exc:
+                    logger.debug(
+                        "Stdio auto-select probe failed (%s)",
+                        type(exc).__name__,
+                        exc_info=True,
+                    )
+                except Exception as exc:
+                    if isinstance(exc, (SystemExit, KeyboardInterrupt)):
+                        raise
+                    logger.debug(
+                        "Stdio auto-select probe failed with unexpected error (%s)",
+                        type(exc).__name__,
+                        exc_info=True,
+                    )
+        except Exception as exc:
+            if isinstance(exc, (SystemExit, KeyboardInterrupt)):
+                raise
+            logger.debug(
+                "Auto-select path encountered an unexpected error (%s)",
+                type(exc).__name__,
+                exc_info=True,
+            )
+
+        return None
+
     async def _inject_unity_instance(self, context: MiddlewareContext) -> None:
         """Inject active Unity instance into context if available."""
         ctx = context.fastmcp_context
 
         active_instance = self.get_active_instance(ctx)
+        if not active_instance:
+            active_instance = await self._maybe_autoselect_instance(ctx)
         if active_instance:
             # If using HTTP transport (PluginHub configured), validate session
             # But for stdio transport (no PluginHub needed or maybe partially configured),

Server/tests/integration/conftest.py

@@ -6,6 +6,9 @@ from pathlib import Path
 SERVER_ROOT = Path(__file__).resolve().parents[2]
 if str(SERVER_ROOT) not in sys.path:
     sys.path.insert(0, str(SERVER_ROOT))
+SERVER_SRC = SERVER_ROOT / "src"
+if str(SERVER_SRC) not in sys.path:
+    sys.path.insert(0, str(SERVER_SRC))
 
 # Ensure telemetry is disabled during test collection and execution to avoid
 # any background network or thread startup that could slow or block pytest.
@@ -86,3 +89,39 @@ fastmcp.server = fastmcp_server
 fastmcp_server.middleware = fastmcp_server_middleware
 sys.modules.setdefault("fastmcp.server", fastmcp_server)
 sys.modules.setdefault("fastmcp.server.middleware", fastmcp_server_middleware)
+
+# Stub minimal starlette modules to avoid optional dependency imports.
+starlette = types.ModuleType("starlette")
+starlette_endpoints = types.ModuleType("starlette.endpoints")
+starlette_websockets = types.ModuleType("starlette.websockets")
+starlette_requests = types.ModuleType("starlette.requests")
+starlette_responses = types.ModuleType("starlette.responses")
+
+
+class _DummyWebSocketEndpoint:
+    pass
+
+
+class _DummyWebSocket:
+    pass
+
+
+class _DummyRequest:
+    pass
+
+
+class _DummyJSONResponse:
+    def __init__(self, *args, **kwargs):
+        pass
+
+
+starlette_endpoints.WebSocketEndpoint = _DummyWebSocketEndpoint
+starlette_websockets.WebSocket = _DummyWebSocket
+starlette_requests.Request = _DummyRequest
+starlette_responses.JSONResponse = _DummyJSONResponse
+
+sys.modules.setdefault("starlette", starlette)
+sys.modules.setdefault("starlette.endpoints", starlette_endpoints)
+sys.modules.setdefault("starlette.websockets", starlette_websockets)
+sys.modules.setdefault("starlette.requests", starlette_requests)
+sys.modules.setdefault("starlette.responses", starlette_responses)

Server/tests/integration/test_instance_autoselect.py

@@ -0,0 +1,144 @@
+import asyncio
+import sys
+import types
+from types import SimpleNamespace
+
+from .test_helpers import DummyContext
+
+
+class DummyMiddlewareContext:
+    def __init__(self, ctx):
+        self.fastmcp_context = ctx
+
+
+def test_auto_selects_single_instance_via_pluginhub(monkeypatch):
+    plugin_hub = types.ModuleType("transport.plugin_hub")
+
+    class PluginHub:
+        @classmethod
+        def is_configured(cls) -> bool:
+            return True
+
+        @classmethod
+        async def get_sessions(cls):
+            raise AssertionError("get_sessions should be stubbed in test")
+
+    plugin_hub.PluginHub = PluginHub
+    monkeypatch.setitem(sys.modules, "transport.plugin_hub", plugin_hub)
+    unity_transport = types.ModuleType("transport.unity_transport")
+    unity_transport._current_transport = lambda: "http"
+    monkeypatch.setitem(sys.modules, "transport.unity_transport", unity_transport)
+    monkeypatch.delitem(sys.modules, "transport.unity_instance_middleware", raising=False)
+
+    from transport.unity_instance_middleware import UnityInstanceMiddleware, PluginHub as ImportedPluginHub
+    assert ImportedPluginHub is plugin_hub.PluginHub
+
+    monkeypatch.setenv("UNITY_MCP_TRANSPORT", "http")
+
+    middleware = UnityInstanceMiddleware()
+    ctx = DummyContext()
+    ctx.client_id = "client-1"
+    middleware_context = DummyMiddlewareContext(ctx)
+
+    call_count = {"sessions": 0}
+
+    async def fake_get_sessions():
+        call_count["sessions"] += 1
+        return SimpleNamespace(
+            sessions={
+                "session-1": SimpleNamespace(project="Ramble", hash="deadbeef"),
+            }
+        )
+
+    monkeypatch.setattr(plugin_hub.PluginHub, "get_sessions", fake_get_sessions)
+
+    selected = asyncio.run(middleware._maybe_autoselect_instance(ctx))
+
+    assert selected == "Ramble@deadbeef"
+    assert middleware.get_active_instance(ctx) == "Ramble@deadbeef"
+    assert call_count["sessions"] == 1
+
+    asyncio.run(middleware._inject_unity_instance(middleware_context))
+
+    assert ctx.get_state("unity_instance") == "Ramble@deadbeef"
+    assert call_count["sessions"] == 1
+
+
+def test_auto_selects_single_instance_via_stdio(monkeypatch):
+    plugin_hub = types.ModuleType("transport.plugin_hub")
+
+    class PluginHub:
+        @classmethod
+        def is_configured(cls) -> bool:
+            return False
+
+    plugin_hub.PluginHub = PluginHub
+    monkeypatch.setitem(sys.modules, "transport.plugin_hub", plugin_hub)
+    unity_transport = types.ModuleType("transport.unity_transport")
+    unity_transport._current_transport = lambda: "stdio"
+    monkeypatch.setitem(sys.modules, "transport.unity_transport", unity_transport)
+    monkeypatch.delitem(sys.modules, "transport.unity_instance_middleware", raising=False)
+
+    from transport.unity_instance_middleware import UnityInstanceMiddleware, PluginHub as ImportedPluginHub
+    assert ImportedPluginHub is plugin_hub.PluginHub
+
+    monkeypatch.setenv("UNITY_MCP_TRANSPORT", "stdio")
+
+    middleware = UnityInstanceMiddleware()
+    ctx = DummyContext()
+    ctx.client_id = "client-1"
+    middleware_context = DummyMiddlewareContext(ctx)
+
+    class PoolStub:
+        def discover_all_instances(self, force_refresh=False):
+            assert force_refresh is True
+            return [SimpleNamespace(id="UnityMCPTests@cc8756d4")]
+
+    unity_connection = types.ModuleType("transport.legacy.unity_connection")
+    unity_connection.get_unity_connection_pool = lambda: PoolStub()
+    monkeypatch.setitem(sys.modules, "transport.legacy.unity_connection", unity_connection)
+
+    selected = asyncio.run(middleware._maybe_autoselect_instance(ctx))
+
+    assert selected == "UnityMCPTests@cc8756d4"
+    assert middleware.get_active_instance(ctx) == "UnityMCPTests@cc8756d4"
+
+    asyncio.run(middleware._inject_unity_instance(middleware_context))
+
+    assert ctx.get_state("unity_instance") == "UnityMCPTests@cc8756d4"
+
+
+def test_auto_select_handles_stdio_errors(monkeypatch):
+    plugin_hub = types.ModuleType("transport.plugin_hub")
+
+    class PluginHub:
+        @classmethod
+        def is_configured(cls) -> bool:
+            return False
+
+    plugin_hub.PluginHub = PluginHub
+    monkeypatch.setitem(sys.modules, "transport.plugin_hub", plugin_hub)
+    unity_transport = types.ModuleType("transport.unity_transport")
+    unity_transport._current_transport = lambda: "stdio"
+    monkeypatch.setitem(sys.modules, "transport.unity_transport", unity_transport)
+    monkeypatch.delitem(sys.modules, "transport.unity_instance_middleware", raising=False)
+
+    from transport.unity_instance_middleware import UnityInstanceMiddleware, PluginHub as ImportedPluginHub
+    assert ImportedPluginHub is plugin_hub.PluginHub
+
+    middleware = UnityInstanceMiddleware()
+    ctx = DummyContext()
+    ctx.client_id = "client-1"
+
+    class PoolStub:
+        def discover_all_instances(self, force_refresh=False):
+            raise ConnectionError("stdio unavailable")
+
+    unity_connection = types.ModuleType("transport.legacy.unity_connection")
+    unity_connection.get_unity_connection_pool = lambda: PoolStub()
+    monkeypatch.setitem(sys.modules, "transport.legacy.unity_connection", unity_connection)
+
+    selected = asyncio.run(middleware._maybe_autoselect_instance(ctx))
+
+    assert selected is None
+    assert middleware.get_active_instance(ctx) is None

TestProjects/UnityMCPTests/Assets/Tests/EditMode/Tools/ManageGameObjectTests.cs

@@ -630,5 +630,137 @@ namespace MCPForUnityTests.Editor.Tools
             UnityEngine.Object.DestroyImmediate(material2);
             UnityEngine.Object.DestroyImmediate(testObject);
         }
+
+        [Test]
+        public void AddComponent_StringArrayFormat_AppliesComponentProperties()
+        {
+            // Arrange - Create a GameObject to add component to
+            var testObject = new GameObject("AddComponentTestObject");
+
+            // Create params using string array format with top-level componentProperties
+            var addComponentParams = new JObject
+            {
+                ["action"] = "add_component",
+                ["target"] = testObject.name,
+                ["search_method"] = "by_name",
+                ["componentsToAdd"] = new JArray { "Rigidbody" },
+                ["componentProperties"] = new JObject
+                {
+                    ["Rigidbody"] = new JObject
+                    {
+                        ["mass"] = 7.5f,
+                        ["useGravity"] = false,
+                        ["drag"] = 2.0f
+                    }
+                }
+            };
+
+            // Act
+            var result = ManageGameObject.HandleCommand(addComponentParams);
+
+            // Assert - Verify component was added
+            var rigidbody = testObject.GetComponent<Rigidbody>();
+            Assert.IsNotNull(rigidbody, "Rigidbody component should be added to GameObject");
+
+            // Verify properties were set correctly during component creation
+            Assert.AreEqual(7.5f, rigidbody.mass, 0.001f,
+                "Mass should be set to 7.5 via componentProperties during add_component");
+            Assert.AreEqual(false, rigidbody.useGravity,
+                "UseGravity should be set to false via componentProperties during add_component");
+            Assert.AreEqual(2.0f, rigidbody.drag, 0.001f,
+                "Drag should be set to 2.0 via componentProperties during add_component");
+
+            // Verify result indicates success
+            Assert.IsNotNull(result, "Should return a result object");
+            var resultObj = result as JObject ?? JObject.FromObject(result);
+            Assert.IsTrue(resultObj.Value<bool>("success"),
+                "Result should indicate success when adding component with properties");
+
+            // Clean up
+            UnityEngine.Object.DestroyImmediate(testObject);
+        }
+
+        [Test]
+        public void AddComponent_ObjectFormat_StillAppliesComponentProperties()
+        {
+            // Arrange - Create a GameObject to add component to
+            var testObject = new GameObject("AddComponentObjectFormatTestObject");
+
+            // Create params using object array format (existing behavior)
+            var addComponentParams = new JObject
+            {
+                ["action"] = "add_component",
+                ["target"] = testObject.name,
+                ["search_method"] = "by_name",
+                ["componentsToAdd"] = new JArray
+                {
+                    new JObject
+                    {
+                        ["typeName"] = "Rigidbody",
+                        ["properties"] = new JObject
+                        {
+                            ["mass"] = 3.5f,
+                            ["useGravity"] = true
+                        }
+                    }
+                }
+            };
+
+            // Act
+            var result = ManageGameObject.HandleCommand(addComponentParams);
+
+            // Assert - Verify component was added
+            var rigidbody = testObject.GetComponent<Rigidbody>();
+            Assert.IsNotNull(rigidbody, "Rigidbody component should be added to GameObject");
+
+            // Verify properties were set correctly
+            Assert.AreEqual(3.5f, rigidbody.mass, 0.001f,
+                "Mass should be set to 3.5 via inline properties");
+            Assert.AreEqual(true, rigidbody.useGravity,
+                "UseGravity should be set to true via inline properties");
+
+            // Clean up
+            UnityEngine.Object.DestroyImmediate(testObject);
+        }
+
+        [Test]
+        public void AddComponent_ComponentNameFormat_AppliesComponentProperties()
+        {
+            // Arrange - Create a GameObject to add component to
+            var testObject = new GameObject("AddComponentNameFormatTestObject");
+
+            // Create params using componentName format (existing behavior)
+            var addComponentParams = new JObject
+            {
+                ["action"] = "add_component",
+                ["target"] = testObject.name,
+                ["search_method"] = "by_name",
+                ["componentName"] = "Rigidbody",
+                ["componentProperties"] = new JObject
+                {
+                    ["Rigidbody"] = new JObject
+                    {
+                        ["mass"] = 5.0f,
+                        ["drag"] = 1.5f
+                    }
+                }
+            };
+
+            // Act
+            var result = ManageGameObject.HandleCommand(addComponentParams);
+
+            // Assert - Verify component was added
+            var rigidbody = testObject.GetComponent<Rigidbody>();
+            Assert.IsNotNull(rigidbody, "Rigidbody component should be added to GameObject");
+
+            // Verify properties were set correctly
+            Assert.AreEqual(5.0f, rigidbody.mass, 0.001f,
+                "Mass should be set to 5.0 via componentName format");
+            Assert.AreEqual(1.5f, rigidbody.drag, 0.001f,
+                "Drag should be set to 1.5 via componentName format");
+
+            // Clean up
+            UnityEngine.Object.DestroyImmediate(testObject);
+        }
     }
 }