Open and close prefabs in the stage view + create them (CoplayDev#283)

* refactor: remove unused UnityEngine references from menu item classes

* Add new tools to manage a prefab, particularly, making them staged.

This might be enough, but it's possible we may have to extract some logic from ManageGameObject

* feat: add AssetPathUtility for asset path normalization and update references in ManageAsset and ManagePrefabs

* feat: add prefab management tools and register them with the MCP server

* feat: update prefab management commands to use 'prefabPath' and add 'create_from_gameobject' action

* fix: update parameter references to 'prefabPath' in ManagePrefabs and manage_prefabs tools

* fix: clarify error message for missing 'prefabPath' in create_from_gameobject command

* fix: ensure pull request triggers for unity tests workflow

* Revert "fix: ensure pull request triggers for unity tests workflow"

This reverts commit 10bfe54.

* Remove delayed execution of executing menu item, fixing CoplayDev#279
This brings the Unity window into focus but that seems to be a better UX for devs.
Also streamline manage_menu_item tool info, as FastMCP recommends

* docs: clarify menu item tool description with guidance to use list action first

* feat: add version update for server_version.txt in bump-version workflow

* fix: simplify error message for failed menu item execution

Author: msanatan

.github/workflows/bump-version.yml

@@ -70,6 +70,9 @@ jobs:
           echo "Updating UnityMcpBridge/UnityMcpServer~/src/pyproject.toml to $NEW_VERSION"
           sed -i '0,/^version = ".*"/s//version = "'"$NEW_VERSION"'"/' "UnityMcpBridge/UnityMcpServer~/src/pyproject.toml"
 
+          echo "Updating UnityMcpBridge/UnityMcpServer~/src/server_version.txt to $NEW_VERSION"
+          echo "$NEW_VERSION" > "UnityMcpBridge/UnityMcpServer~/src/server_version.txt"
+
       - name: Commit and push changes
         env:
           NEW_VERSION: ${{ steps.compute.outputs.new_version }}
@@ -78,7 +81,7 @@ jobs:
           set -euo pipefail
           git config user.name "GitHub Actions"
           git config user.email "actions@github.com"
-          git add UnityMcpBridge/package.json "UnityMcpBridge/UnityMcpServer~/src/pyproject.toml"
+          git add UnityMcpBridge/package.json "UnityMcpBridge/UnityMcpServer~/src/pyproject.toml" "UnityMcpBridge/UnityMcpServer~/src/server_version.txt"
           if git diff --cached --quiet; then
             echo "No version changes to commit."
           else

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

@@ -0,0 +1,255 @@
+using System.IO;
+using Newtonsoft.Json.Linq;
+using NUnit.Framework;
+using UnityEditor;
+using UnityEditor.SceneManagement;
+using UnityEngine;
+using MCPForUnity.Editor.Tools.Prefabs;
+using MCPForUnity.Editor.Tools;
+
+namespace MCPForUnityTests.Editor.Tools
+{
+    public class ManagePrefabsTests
+    {
+        private const string TempDirectory = "Assets/Temp/ManagePrefabsTests";
+
+        [SetUp]
+        public void SetUp()
+        {
+            StageUtility.GoToMainStage();
+            EnsureTempDirectoryExists();
+        }
+
+        [TearDown]
+        public void TearDown()
+        {
+            StageUtility.GoToMainStage();
+        }
+
+        [OneTimeTearDown]
+        public void CleanupAll()
+        {
+            StageUtility.GoToMainStage();
+            if (AssetDatabase.IsValidFolder(TempDirectory))
+            {
+                AssetDatabase.DeleteAsset(TempDirectory);
+            }
+        }
+
+        [Test]
+        public void OpenStage_OpensPrefabInIsolation()
+        {
+            string prefabPath = CreateTestPrefab("OpenStageCube");
+
+            try
+            {
+                var openParams = new JObject
+                {
+                    ["action"] = "open_stage",
+                    ["prefabPath"] = prefabPath
+                };
+
+                var openResult = ToJObject(ManagePrefabs.HandleCommand(openParams));
+
+                Assert.IsTrue(openResult.Value<bool>("success"), "open_stage should succeed for a valid prefab.");
+
+                PrefabStage stage = PrefabStageUtility.GetCurrentPrefabStage();
+                Assert.IsNotNull(stage, "Prefab stage should be open after open_stage.");
+                Assert.AreEqual(prefabPath, stage.assetPath, "Opened stage should match prefab path.");
+
+                var stageInfo = ToJObject(ManageEditor.HandleCommand(new JObject { ["action"] = "get_prefab_stage" }));
+                Assert.IsTrue(stageInfo.Value<bool>("success"), "get_prefab_stage should succeed when stage is open.");
+
+                var data = stageInfo["data"] as JObject;
+                Assert.IsNotNull(data, "Stage info should include data payload.");
+                Assert.IsTrue(data.Value<bool>("isOpen"));
+                Assert.AreEqual(prefabPath, data.Value<string>("assetPath"));
+            }
+            finally
+            {
+                StageUtility.GoToMainStage();
+                AssetDatabase.DeleteAsset(prefabPath);
+            }
+        }
+
+        [Test]
+        public void CloseStage_ReturnsSuccess_WhenNoStageOpen()
+        {
+            StageUtility.GoToMainStage();
+            var closeResult = ToJObject(ManagePrefabs.HandleCommand(new JObject
+            {
+                ["action"] = "close_stage"
+            }));
+
+            Assert.IsTrue(closeResult.Value<bool>("success"), "close_stage should succeed even if no stage is open.");
+        }
+
+        [Test]
+        public void CloseStage_ClosesOpenPrefabStage()
+        {
+            string prefabPath = CreateTestPrefab("CloseStageCube");
+
+            try
+            {
+                ManagePrefabs.HandleCommand(new JObject
+                {
+                    ["action"] = "open_stage",
+                    ["prefabPath"] = prefabPath
+                });
+
+                var closeResult = ToJObject(ManagePrefabs.HandleCommand(new JObject
+                {
+                    ["action"] = "close_stage"
+                }));
+
+                Assert.IsTrue(closeResult.Value<bool>("success"), "close_stage should succeed when stage is open.");
+                Assert.IsNull(PrefabStageUtility.GetCurrentPrefabStage(), "Prefab stage should be closed after close_stage.");
+            }
+            finally
+            {
+                StageUtility.GoToMainStage();
+                AssetDatabase.DeleteAsset(prefabPath);
+            }
+        }
+
+        [Test]
+        public void SaveOpenStage_SavesDirtyChanges()
+        {
+            string prefabPath = CreateTestPrefab("SaveStageCube");
+
+            try
+            {
+                ManagePrefabs.HandleCommand(new JObject
+                {
+                    ["action"] = "open_stage",
+                    ["prefabPath"] = prefabPath
+                });
+
+                PrefabStage stage = PrefabStageUtility.GetCurrentPrefabStage();
+                Assert.IsNotNull(stage, "Stage should be open before modifying.");
+
+                stage.prefabContentsRoot.transform.localScale = new Vector3(2f, 2f, 2f);
+
+                var saveResult = ToJObject(ManagePrefabs.HandleCommand(new JObject
+                {
+                    ["action"] = "save_open_stage"
+                }));
+
+                Assert.IsTrue(saveResult.Value<bool>("success"), "save_open_stage should succeed when stage is open.");
+                Assert.IsFalse(stage.scene.isDirty, "Stage scene should not be dirty after saving.");
+
+                GameObject reloaded = AssetDatabase.LoadAssetAtPath<GameObject>(prefabPath);
+                Assert.AreEqual(new Vector3(2f, 2f, 2f), reloaded.transform.localScale, "Saved prefab asset should include changes from open stage.");
+            }
+            finally
+            {
+                StageUtility.GoToMainStage();
+                AssetDatabase.DeleteAsset(prefabPath);
+            }
+        }
+
+        [Test]
+        public void SaveOpenStage_ReturnsError_WhenNoStageOpen()
+        {
+            StageUtility.GoToMainStage();
+
+            var saveResult = ToJObject(ManagePrefabs.HandleCommand(new JObject
+            {
+                ["action"] = "save_open_stage"
+            }));
+
+            Assert.IsFalse(saveResult.Value<bool>("success"), "save_open_stage should fail when no stage is open.");
+        }
+
+        [Test]
+        public void CreateFromGameObject_CreatesPrefabAndLinksInstance()
+        {
+            EnsureTempDirectoryExists();
+            StageUtility.GoToMainStage();
+
+            string prefabPath = Path.Combine(TempDirectory, "SceneObjectSaved.prefab").Replace('\\', '/');
+            GameObject sceneObject = new GameObject("ScenePrefabSource");
+
+            try
+            {
+                var result = ToJObject(ManagePrefabs.HandleCommand(new JObject
+                {
+                    ["action"] = "create_from_gameobject",
+                    ["target"] = sceneObject.name,
+                    ["prefabPath"] = prefabPath
+                }));
+
+                Assert.IsTrue(result.Value<bool>("success"), "create_from_gameobject should succeed for a valid scene object.");
+
+                var data = result["data"] as JObject;
+                Assert.IsNotNull(data, "Response data should include prefab information.");
+
+                string savedPath = data.Value<string>("prefabPath");
+                Assert.AreEqual(prefabPath, savedPath, "Returned prefab path should match the requested path.");
+
+                GameObject prefabAsset = AssetDatabase.LoadAssetAtPath<GameObject>(savedPath);
+                Assert.IsNotNull(prefabAsset, "Prefab asset should exist at the saved path.");
+
+                int instanceId = data.Value<int>("instanceId");
+                var linkedInstance = EditorUtility.InstanceIDToObject(instanceId) as GameObject;
+                Assert.IsNotNull(linkedInstance, "Linked instance should resolve from instanceId.");
+                Assert.AreEqual(savedPath, PrefabUtility.GetPrefabAssetPathOfNearestInstanceRoot(linkedInstance), "Instance should be connected to the new prefab.");
+
+                sceneObject = linkedInstance;
+            }
+            finally
+            {
+                if (AssetDatabase.LoadAssetAtPath<UnityEngine.Object>(prefabPath) != null)
+                {
+                    AssetDatabase.DeleteAsset(prefabPath);
+                }
+
+                if (sceneObject != null)
+                {
+                    if (PrefabUtility.IsPartOfPrefabInstance(sceneObject))
+                    {
+                        PrefabUtility.UnpackPrefabInstance(
+                            sceneObject,
+                            PrefabUnpackMode.Completely,
+                            InteractionMode.AutomatedAction
+                        );
+                    }
+                    UnityEngine.Object.DestroyImmediate(sceneObject, true);
+                }
+            }
+        }
+
+        private static string CreateTestPrefab(string name)
+        {
+            EnsureTempDirectoryExists();
+
+            GameObject temp = GameObject.CreatePrimitive(PrimitiveType.Cube);
+            temp.name = name;
+
+            string path = Path.Combine(TempDirectory, name + ".prefab").Replace('\\', '/');
+            PrefabUtility.SaveAsPrefabAsset(temp, path, out bool success);
+            UnityEngine.Object.DestroyImmediate(temp);
+
+            Assert.IsTrue(success, "PrefabUtility.SaveAsPrefabAsset should succeed for test prefab.");
+            return path;
+        }
+
+        private static void EnsureTempDirectoryExists()
+        {
+            if (!AssetDatabase.IsValidFolder("Assets/Temp"))
+            {
+                AssetDatabase.CreateFolder("Assets", "Temp");
+            }
+
+            if (!AssetDatabase.IsValidFolder(TempDirectory))
+            {
+                AssetDatabase.CreateFolder("Assets/Temp", "ManagePrefabsTests");
+            }
+        }
+
+        private static JObject ToJObject(object result)
+        {
+            return result as JObject ?? JObject.FromObject(result);
+        }
+    }
+}

TestProjects/UnityMCPTests/Assets/Tests/EditMode/Tools/ManagePrefabsTests.cs.meta

@@ -0,0 +1,29 @@
+using System;
+
+namespace MCPForUnity.Editor.Helpers
+{
+    /// <summary>
+    /// Provides common utility methods for working with Unity asset paths.
+    /// </summary>
+    public static class AssetPathUtility
+    {
+        /// <summary>
+        /// Normalizes a Unity asset path by ensuring forward slashes are used and that it is rooted under "Assets/".
+        /// </summary>
+        public static string SanitizeAssetPath(string path)
+        {
+            if (string.IsNullOrEmpty(path))
+            {
+                return path;
+            }
+
+            path = path.Replace('\\', '/');
+            if (!path.StartsWith("Assets/", StringComparison.OrdinalIgnoreCase))
+            {
+                return "Assets/" + path.TrimStart('/');
+            }
+
+            return path;
+        }
+    }
+}

UnityMcpBridge/Editor/Helpers/AssetPathUtility.cs

@@ -15,6 +15,7 @@
 using MCPForUnity.Editor.Models;
 using MCPForUnity.Editor.Tools;
 using MCPForUnity.Editor.Tools.MenuItems;
+using MCPForUnity.Editor.Tools.Prefabs;
 
 namespace MCPForUnity.Editor
 {
@@ -1040,7 +1041,26 @@ private static string ExecuteCommand(Command command)
                 // Use JObject for parameters as the new handlers likely expect this
                 JObject paramsObject = command.@params ?? new JObject();
 
-                object result = CommandRegistry.GetHandler(command.type)(paramsObject);
+                // Route command based on the new tool structure from the refactor plan
+                object result = command.type switch
+                {
+                    // Maps the command type (tool name) to the corresponding handler's static HandleCommand method
+                    // Assumes each handler class has a static method named 'HandleCommand' that takes JObject parameters
+                    "manage_script" => ManageScript.HandleCommand(paramsObject),
+                    // Run scene operations on the main thread to avoid deadlocks/hangs (with diagnostics under debug flag)
+                    "manage_scene" => HandleManageScene(paramsObject)
+                        ?? throw new TimeoutException($"manage_scene timed out after {FrameIOTimeoutMs} ms on main thread"),
+                    "manage_editor" => ManageEditor.HandleCommand(paramsObject),
+                    "manage_gameobject" => ManageGameObject.HandleCommand(paramsObject),
+                    "manage_asset" => ManageAsset.HandleCommand(paramsObject),
+                    "manage_shader" => ManageShader.HandleCommand(paramsObject),
+                    "read_console" => ReadConsole.HandleCommand(paramsObject),
+                    "manage_menu_item" => ManageMenuItem.HandleCommand(paramsObject),
+                    "manage_prefabs" => ManagePrefabs.HandleCommand(paramsObject),
+                    _ => throw new ArgumentException(
+                        $"Unknown or unsupported command type: {command.type}"
+                    ),
+                };
 
                 // Standard success response format
                 var response = new { status = "success", result };