diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1596a22..7d7ae80 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,23 @@ This project follows a simple changelog format inspired by [Keep a Changelog](ht
 
 ## [Unreleased]
 
+## [0.3.0] - 2026-05-20
+
+### Added
+
+- Added MCP `outputSchema` and `annotations` to listed tools.
+- Added a standard structured tool result envelope with `ok`, `tool`, `callId`, `summary`, `data`, and follow-up `refs`.
+- Added prefab workflow tools: `inspect_prefab`, `validate_prefab_references`, `duplicate_prefab`, `edit_prefab_json`, `create_prefab_instance`, `inspect_prefab_instance`, `apply_prefab_instance`, and `revert_prefab_instance`.
+- Added `get_performance_snapshot` and expanded `validate_scene` with scene scale/performance-oriented counters.
+- Added project AI instruction tools: `list_project_instructions`, `read_project_instruction`, `write_project_instruction`, and `create_project_skill`.
+- Added tests for tool metadata, result envelopes, and project instruction helpers.
+
+### Changed
+
+- Expanded the default `core` profile from 28 tools to 34 tools.
+- Expanded the `full` profile from 76 tools to 89 tools.
+- Updated tool interaction logs to store concise result summaries from the standard envelope.
+
 ## [0.2.0] - 2026-05-20
 
 ### Added
diff --git a/README.md b/README.md
index 89ba032..07b88a2 100644
--- a/README.md
+++ b/README.md
@@ -199,9 +199,10 @@ Try a higher-level prompt in your AI client:
 - This extension is **Editor-only**. It is meant to automate Cocos Creator, not to add runtime dependencies to your final game build.
 - The MCP server listens on `http://127.0.0.1:8765/` by default.
 - If the configured port is busy, the server automatically falls back to the next available port and the panel/client config use the actual running port.
-- The default `core` profile exposes 28 high-signal tools. Switch to `full` for all 76 tools, or use `custom` to include/exclude tool categories and individual tools.
+- The default `core` profile exposes 34 high-signal tools. Switch to `full` for all 89 tools, or use `custom` to include/exclude tool categories and individual tools.
 - The panel includes a manual update check against the latest GitHub release.
 - Streamable HTTP responses follow the MCP transport requirements for `Accept`, `MCP-Protocol-Version`, JSON-RPC notifications/responses, and optional `Mcp-Session-Id` sessions.
+- Tool listings include MCP `outputSchema` and `annotations`; structured tool results use a standard envelope with `ok`, `tool`, `callId`, `summary`, `data`, and follow-up `refs`.
 - All exposed MCP tools execute directly. There is no extra approval toggle inside the Cocos extension.
 - File tools and `cocos://asset/path/...` resources are restricted to the active Cocos project root.
 - The recommended workflow is `execute_javascript` first, then focused helper tools for screenshots, diagnostics, assets, and inspection.
@@ -218,7 +219,7 @@ Try a higher-level prompt in your AI client:
 
 ## Highlights
 
-- **76 Built-in Tools** — Scene hierarchy, editor state, selection workflows, assets, UI creation, components, files, logs, script diagnostics, screenshots, runtime control, and input simulation
+- **89 Built-in Tools** — Scene hierarchy, editor state, selection workflows, prefabs, assets, project instructions, UI creation, components, files, logs, script diagnostics, screenshots, runtime control, and input simulation
 - **Primary Unified Tool** — `execute_javascript` supports both `scene` and `editor` contexts
 - **Resources & Prompts** — Live project/log resources plus reusable workflows like script fixing, scene validation, and playable prototype creation
 - **Cocos Panel UI** — A minimal `Funplay > MCP Server` panel for service management, update checks, tool exposure, and MCP client setup
@@ -235,20 +236,20 @@ Funplay MCP for Cocos follows the same design principles as Funplay MCP for Unit
 | Embedded server | Built-in HTTP MCP server | Built-in HTTP MCP server |
 | Primary execution tool | `execute_javascript` | `execute_code` |
 | Primary language | JavaScript in scene/editor contexts | C# in Unity editor/runtime contexts |
-| Default profile | `core` with 28 tools | `core` focused tool profile |
-| Full profile | 76 tools plus `custom` exposure | 79 tools |
+| Default profile | `core` with 34 tools | `core` focused tool profile |
+| Full profile | 89 tools plus `custom` exposure | 79 tools |
 | Client setup | One-click config panel | One-click config window |
 
 ## MCP Capabilities
 
 The current package exposes four capability layers:
 
-- **Tools** — 28 tools in `core`, 76 tools in `full`, plus `custom` include/exclude rules
+- **Tools** — 34 tools in `core`, 89 tools in `full`, plus `custom` include/exclude rules
 - **Primary execution** — `execute_javascript` for scene/runtime and editor/browser automation
 - **Prompts** — `fix_script_errors`, `create_playable_prototype`, `scene_validation`, and `auto_wire_scene`
 - **Resources** — project context, scene summaries, current selection, script diagnostics, asset selection, logs, and MCP interaction history
 
-The default `core` set is intentionally small: `execute_javascript`, `execute_scene_script`, `execute_editor_script`, `get_editor_state`, `get_tool_catalog`, `check_for_updates`, `get_selection`, `set_selection`, `get_project_info`, `get_scene_info`, `get_hierarchy`, `list_scenes`, `open_scene`, `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `run_script_diagnostics`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene`, `get_script_diagnostic_context`, `get_runtime_state`, `capture_editor_screenshot`, `capture_scene_screenshot`, `capture_preview_screenshot`, and `list_editor_windows`.
+The default `core` set is intentionally small: `execute_javascript`, `execute_scene_script`, `execute_editor_script`, `get_editor_state`, `get_tool_catalog`, `check_for_updates`, `get_selection`, `list_project_instructions`, `read_project_instruction`, `set_selection`, `get_project_info`, `get_scene_info`, `get_hierarchy`, `list_scenes`, `open_scene`, `inspect_prefab`, `validate_prefab_references`, `inspect_prefab_instance`, `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `run_script_diagnostics`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene`, `get_performance_snapshot`, `get_script_diagnostic_context`, `get_runtime_state`, `capture_editor_screenshot`, `capture_scene_screenshot`, `capture_preview_screenshot`, and `list_editor_windows`.
 
 ## Built-in Resources
 
@@ -267,21 +268,22 @@ The default `core` set is intentionally small: `execute_javascript`, `execute_sc
 
 ## Built-in Tools
 
-Funplay MCP for Cocos currently ships with **76 tool functions** in the `full` profile:
+Funplay MCP for Cocos currently ships with **89 tool functions** in the `full` profile:
 
 | Category | Tools |
 |----------|-------|
 | **Script Execution** | `execute_javascript`, `execute_scene_script`, `execute_editor_script` |
 | **Editor State** | `get_editor_state`, `get_tool_catalog`, `check_for_updates`, `get_selection`, `set_selection`, `get_editor_selection` |
+| **Project Instructions** | `list_project_instructions`, `read_project_instruction`, `write_project_instruction`, `create_project_skill` |
 | **Project & Scene** | `get_project_info`, `get_scene_info`, `get_hierarchy`, `find_nodes`, `inspect_node`, `list_scenes`, `open_scene`, `run_scene_asset` |
 | **Node Editing** | `create_node`, `delete_node`, `set_node_transform` |
-| **Assets & Prefabs** | `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `delete_asset`, `list_prefabs`, `instantiate_prefab`, `get_editor_selection` |
+| **Assets & Prefabs** | `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `delete_asset`, `list_prefabs`, `inspect_prefab`, `validate_prefab_references`, `duplicate_prefab`, `edit_prefab_json`, `create_prefab_instance`, `inspect_prefab_instance`, `apply_prefab_instance`, `revert_prefab_instance`, `instantiate_prefab` |
 | **Components** | `list_components`, `inspect_component`, `add_component`, `remove_component`, `set_component_property`, `reset_component_property` |
 | **UI** | `create_canvas`, `create_label`, `create_button`, `create_sprite` |
 | **Camera** | `list_cameras`, `create_camera`, `set_camera_properties` |
 | **Animation** | `list_animations`, `add_animation_clip`, `play_animation`, `stop_animation` |
 | **Files** | `read_file`, `get_file_snippet`, `write_file`, `replace_in_file`, `search_files`, `list_directory`, `exists`, `refresh_assets` |
-| **Diagnostics & Logs** | `run_script_diagnostics`, `get_script_diagnostic_context`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene` |
+| **Diagnostics & Logs** | `run_script_diagnostics`, `get_script_diagnostic_context`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene`, `get_performance_snapshot` |
 | **Runtime** | `get_runtime_state`, `pause_runtime`, `resume_runtime`, `set_time_scale` |
 | **Interaction** | `emit_node_event`, `simulate_button_click`, `invoke_component_method`, `simulate_mouse_click`, `simulate_mouse_drag`, `simulate_key_press`, `simulate_key_combo`, `simulate_preview_input` |
 | **Screenshots & Windows** | `capture_desktop_screenshot`, `capture_editor_screenshot`, `capture_scene_screenshot`, `capture_game_screenshot`, `capture_preview_screenshot`, `list_editor_windows` |
diff --git a/README_CN.md b/README_CN.md
index ecbea9b..9724272 100644
--- a/README_CN.md
+++ b/README_CN.md
@@ -199,9 +199,10 @@ url = "http://127.0.0.1:8765/"
 - 这是一个 **仅限 Editor** 的扩展，用于自动化 Cocos Creator，不会给最终游戏包添加运行时依赖。
 - MCP Server 默认监听 `http://127.0.0.1:8765/`。
 - 如果配置端口被占用，服务会自动回退到下一个可用端口，面板与一键客户端配置会使用实际运行端口。
-- 默认 `core` profile 暴露 28 个高频工具；如果需要完整工具集，可在面板切到 `full`，暴露全部 76 个工具；也可以用 `custom` 按分类或工具名增删。
+- 默认 `core` profile 暴露 34 个高频工具；如果需要完整工具集，可在面板切到 `full`，暴露全部 89 个工具；也可以用 `custom` 按分类或工具名增删。
 - 面板提供手动更新检查，会对比当前安装版本和 GitHub 最新 Release。
 - Streamable HTTP 响应已补齐 MCP 传输层要求，包括 `Accept`、`MCP-Protocol-Version`、JSON-RPC notification/response，以及可选 `Mcp-Session-Id` session。
+- 工具列表会包含 MCP `outputSchema` 和 `annotations`；结构化工具结果统一使用包含 `ok`、`tool`、`callId`、`summary`、`data`、`refs` 的标准 envelope。
 - 所有已暴露的 MCP 工具都会直接执行，Cocos 扩展里没有额外 approval 开关。
 - 文件工具和 `cocos://asset/path/...` 资源默认只能访问当前 Cocos 项目根目录内的路径。
 - 推荐工作流是优先使用 `execute_javascript`，再配合截图、诊断、资产、检查类工具。
@@ -218,7 +219,7 @@ url = "http://127.0.0.1:8765/"
 
 ## 核心特性
 
-- **76 个内置工具** — 覆盖场景层级、编辑器状态、选择工作流、资产、UI 创建、组件、文件、日志、脚本诊断、截图、运行态控制和输入模拟
+- **89 个内置工具** — 覆盖场景层级、编辑器状态、选择工作流、Prefab、资产、项目指令、UI 创建、组件、文件、日志、脚本诊断、截图、运行态控制和输入模拟
 - **统一主工具** — `execute_javascript` 同时支持 `scene` 和 `editor` 两种上下文
 - **Resources 与 Prompts** — 实时项目/日志资源，以及脚本修复、场景验证、可玩原型等可复用工作流
 - **Cocos 图形面板** — `Funplay > MCP Server` 提供服务管理、更新检查、工具暴露和 MCP 客户端配置
@@ -235,20 +236,20 @@ Funplay MCP for Cocos 延续 Funplay MCP for Unity 的设计原则，并针对 C
 | 内置服务 | 内嵌 HTTP MCP Server | 内嵌 HTTP MCP Server |
 | 主执行工具 | `execute_javascript` | `execute_code` |
 | 主语言 | 场景/编辑器上下文中的 JavaScript | Unity 编辑器/运行态中的 C# |
-| 默认工具集 | `core`，28 个工具 | 聚焦版 `core` 工具集 |
-| 完整工具集 | 76 个工具，并支持 `custom` 暴露 | 79 个工具 |
+| 默认工具集 | `core`，34 个工具 | 聚焦版 `core` 工具集 |
+| 完整工具集 | 89 个工具，并支持 `custom` 暴露 | 79 个工具 |
 | 客户端配置 | 一键配置面板 | 一键配置窗口 |
 
 ## MCP 能力结构
 
 当前包提供四层能力：
 
-- **Tools** — `core` 下 28 个工具，`full` 下 76 个工具，并支持 `custom` include/exclude 规则
+- **Tools** — `core` 下 34 个工具，`full` 下 89 个工具，并支持 `custom` include/exclude 规则
 - **Primary execution** — `execute_javascript` 用于场景/运行态和编辑器/browser 自动化
 - **Prompts** — `fix_script_errors`、`create_playable_prototype`、`scene_validation`、`auto_wire_scene`
 - **Resources** — 项目上下文、场景摘要、当前选择、脚本诊断、资产选择、日志和 MCP 交互历史
 
-当前默认 `core` 工具集刻意保持精简，只包含：`execute_javascript`、`execute_scene_script`、`execute_editor_script`、`get_editor_state`、`get_tool_catalog`、`check_for_updates`、`get_selection`、`set_selection`、`get_project_info`、`get_scene_info`、`get_hierarchy`、`list_scenes`、`open_scene`、`list_assets`、`inspect_asset`、`open_asset`、`select_asset`、`run_script_diagnostics`、`get_recent_logs`、`search_project_logs`、`clear_logs`、`validate_scene`、`get_script_diagnostic_context`、`get_runtime_state`、`capture_editor_screenshot`、`capture_scene_screenshot`、`capture_preview_screenshot`、`list_editor_windows`。
+当前默认 `core` 工具集刻意保持精简，只包含：`execute_javascript`、`execute_scene_script`、`execute_editor_script`、`get_editor_state`、`get_tool_catalog`、`check_for_updates`、`get_selection`、`list_project_instructions`、`read_project_instruction`、`set_selection`、`get_project_info`、`get_scene_info`、`get_hierarchy`、`list_scenes`、`open_scene`、`inspect_prefab`、`validate_prefab_references`、`inspect_prefab_instance`、`list_assets`、`inspect_asset`、`open_asset`、`select_asset`、`run_script_diagnostics`、`get_recent_logs`、`search_project_logs`、`clear_logs`、`validate_scene`、`get_performance_snapshot`、`get_script_diagnostic_context`、`get_runtime_state`、`capture_editor_screenshot`、`capture_scene_screenshot`、`capture_preview_screenshot`、`list_editor_windows`。
 
 ## 内置 Resources
 
@@ -267,21 +268,22 @@ Funplay MCP for Cocos 延续 Funplay MCP for Unity 的设计原则，并针对 C
 
 ## 内置工具
 
-Funplay MCP for Cocos 当前在 `full` profile 下提供 **76 个工具函数**：
+Funplay MCP for Cocos 当前在 `full` profile 下提供 **89 个工具函数**：
 
 | 分类 | 工具 |
 |------|------|
 | **脚本执行** | `execute_javascript`, `execute_scene_script`, `execute_editor_script` |
 | **编辑器状态** | `get_editor_state`, `get_tool_catalog`, `check_for_updates`, `get_selection`, `set_selection`, `get_editor_selection` |
+| **项目指令** | `list_project_instructions`, `read_project_instruction`, `write_project_instruction`, `create_project_skill` |
 | **项目与场景** | `get_project_info`, `get_scene_info`, `get_hierarchy`, `find_nodes`, `inspect_node`, `list_scenes`, `open_scene`, `run_scene_asset` |
 | **节点编辑** | `create_node`, `delete_node`, `set_node_transform` |
-| **资产与 Prefab** | `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `delete_asset`, `list_prefabs`, `instantiate_prefab`, `get_editor_selection` |
+| **资产与 Prefab** | `list_assets`, `inspect_asset`, `open_asset`, `select_asset`, `delete_asset`, `list_prefabs`, `inspect_prefab`, `validate_prefab_references`, `duplicate_prefab`, `edit_prefab_json`, `create_prefab_instance`, `inspect_prefab_instance`, `apply_prefab_instance`, `revert_prefab_instance`, `instantiate_prefab` |
 | **组件** | `list_components`, `inspect_component`, `add_component`, `remove_component`, `set_component_property`, `reset_component_property` |
 | **UI** | `create_canvas`, `create_label`, `create_button`, `create_sprite` |
 | **相机** | `list_cameras`, `create_camera`, `set_camera_properties` |
 | **动画** | `list_animations`, `add_animation_clip`, `play_animation`, `stop_animation` |
 | **文件** | `read_file`, `get_file_snippet`, `write_file`, `replace_in_file`, `search_files`, `list_directory`, `exists`, `refresh_assets` |
-| **诊断与日志** | `run_script_diagnostics`, `get_script_diagnostic_context`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene` |
+| **诊断与日志** | `run_script_diagnostics`, `get_script_diagnostic_context`, `get_recent_logs`, `search_project_logs`, `clear_logs`, `validate_scene`, `get_performance_snapshot` |
 | **运行态** | `get_runtime_state`, `pause_runtime`, `resume_runtime`, `set_time_scale` |
 | **交互** | `emit_node_event`, `simulate_button_click`, `invoke_component_method`, `simulate_mouse_click`, `simulate_mouse_drag`, `simulate_key_press`, `simulate_key_combo`, `simulate_preview_input` |
 | **截图与窗口** | `capture_desktop_screenshot`, `capture_editor_screenshot`, `capture_scene_screenshot`, `capture_game_screenshot`, `capture_preview_screenshot`, `list_editor_windows` |
diff --git a/lib/prefabs.js b/lib/prefabs.js
new file mode 100644
index 0000000..a2dbc86
--- /dev/null
+++ b/lib/prefabs.js
@@ -0,0 +1,269 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const { listAssets, queryAssetData, queryAssetInfo, queryAssetMeta } = require('./assets');
+const { resolveProjectPath } = require('./path-safety');
+
+function requestEditorMessage(channel, method, ...args) {
+  if (!global.Editor || !Editor.Message || typeof Editor.Message.request !== 'function') {
+    throw new Error('Editor.Message.request is unavailable in the Cocos extension host.');
+  }
+  return Editor.Message.request(channel, method, ...args);
+}
+
+function assetUrlToPath(projectPath, url) {
+  if (!url || !String(url).startsWith('db://assets/')) {
+    return '';
+  }
+  return path.join(projectPath, String(url).slice('db://'.length));
+}
+
+function assetFilePath(projectPath, info) {
+  const candidates = [
+    info && info.file,
+    info && info.path,
+    info && info.source,
+    info && info.url ? assetUrlToPath(projectPath, info.url) : '',
+  ].filter(Boolean);
+
+  for (const candidate of candidates) {
+    const fullPath = path.isAbsolute(candidate)
+      ? resolveProjectPath(projectPath, candidate)
+      : resolveProjectPath(projectPath, candidate);
+    if (fs.existsSync(fullPath) && fs.statSync(fullPath).isFile()) {
+      return fullPath;
+    }
+  }
+  return '';
+}
+
+function collectUuidReferences(value, refs = [], pointer = '') {
+  if (!value || typeof value !== 'object') {
+    return refs;
+  }
+
+  if (Array.isArray(value)) {
+    value.forEach((item, index) => collectUuidReferences(item, refs, `${pointer}/${index}`));
+    return refs;
+  }
+
+  for (const [key, child] of Object.entries(value)) {
+    const childPointer = `${pointer}/${key}`;
+    if (
+      typeof child === 'string' &&
+      (key.toLowerCase().includes('uuid') || key === '__uuid__' || key === 'assetUuid' || key === 'prefabUuid')
+    ) {
+      refs.push({ uuid: child, path: childPointer, key });
+    } else {
+      collectUuidReferences(child, refs, childPointer);
+    }
+  }
+  return refs;
+}
+
+function getByJsonPath(target, jsonPath) {
+  const segments = String(jsonPath || '')
+    .replace(/^\//, '')
+    .split(/[/.]/)
+    .map((segment) => segment.trim())
+    .filter(Boolean);
+  let current = target;
+  for (const segment of segments) {
+    if (current == null) {
+      return undefined;
+    }
+    current = current[segment];
+  }
+  return current;
+}
+
+function setByJsonPath(target, jsonPath, value) {
+  const segments = String(jsonPath || '')
+    .replace(/^\//, '')
+    .split(/[/.]/)
+    .map((segment) => segment.trim())
+    .filter(Boolean);
+  if (!segments.length) {
+    throw new Error('jsonPath is required.');
+  }
+  let current = target;
+  for (let index = 0; index < segments.length - 1; index += 1) {
+    const segment = segments[index];
+    if (current[segment] == null || typeof current[segment] !== 'object') {
+      current[segment] = {};
+    }
+    current = current[segment];
+  }
+  current[segments[segments.length - 1]] = value;
+}
+
+async function inspectPrefab(projectPath, target) {
+  const info = await queryAssetInfo(target);
+  const meta = await queryAssetMeta(target).catch(() => null);
+  const data = await queryAssetData(target).catch(() => null);
+  const filePath = assetFilePath(projectPath, info);
+  const content = filePath ? fs.readFileSync(filePath, 'utf8') : '';
+  const parsed = content ? JSON.parse(content) : data;
+  const references = collectUuidReferences(parsed).slice(0, 500);
+
+  return {
+    info,
+    meta,
+    filePath: filePath ? path.relative(projectPath, filePath).replace(/\\/g, '/') : '',
+    referenceCount: references.length,
+    references,
+  };
+}
+
+async function validatePrefabReferences(projectPath, options = {}) {
+  const targets = options.target
+    ? [options.target]
+    : (await listAssets({ pattern: options.pattern || 'db://assets/**', ccType: 'cc.Prefab' }))
+        .slice(0, Number.isFinite(options.limit) ? Math.max(1, Math.min(200, options.limit)) : 50)
+        .map((asset) => asset.uuid || asset.url)
+        .filter(Boolean);
+  const prefabs = [];
+
+  for (const target of targets) {
+    const prefab = await inspectPrefab(projectPath, target);
+    const checked = [];
+    const missing = [];
+    for (const ref of prefab.references) {
+      try {
+        const info = await queryAssetInfo(ref.uuid);
+        checked.push({ ...ref, exists: true, asset: { uuid: info.uuid, url: info.url, type: info.type } });
+      } catch (error) {
+        missing.push({ ...ref, exists: false, error: error.message });
+      }
+    }
+    prefabs.push({
+      target,
+      filePath: prefab.filePath,
+      referenceCount: prefab.referenceCount,
+      checkedCount: checked.length + missing.length,
+      missingCount: missing.length,
+      missing,
+    });
+  }
+
+  const missingCount = prefabs.reduce((sum, prefab) => sum + prefab.missingCount, 0);
+  return {
+    ok: missingCount === 0,
+    prefabCount: prefabs.length,
+    missingCount,
+    prefabs,
+  };
+}
+
+async function duplicatePrefab(projectPath, options = {}) {
+  const source = String(options.source || '').trim();
+  const target = String(options.target || '').trim();
+  if (!source || !target) {
+    throw new Error('source and target are required.');
+  }
+
+  const info = await queryAssetInfo(source);
+  const sourcePath = assetFilePath(projectPath, info);
+  if (!sourcePath) {
+    throw new Error(`Prefab source file was not found: ${source}`);
+  }
+
+  const targetPath = resolveProjectPath(projectPath, target.endsWith('.prefab') ? target : `${target}.prefab`);
+  const assetsRoot = path.join(projectPath, 'assets');
+  const relativeToAssets = path.relative(assetsRoot, targetPath);
+  if (relativeToAssets.startsWith('..') || path.isAbsolute(relativeToAssets)) {
+    throw new Error('target must be inside the Cocos assets directory.');
+  }
+  if (fs.existsSync(targetPath) && options.overwrite !== true) {
+    throw new Error(`Target prefab already exists: ${target}`);
+  }
+
+  fs.mkdirSync(path.dirname(targetPath), { recursive: true });
+  fs.copyFileSync(sourcePath, targetPath);
+  return {
+    duplicated: true,
+    source: path.relative(projectPath, sourcePath).replace(/\\/g, '/'),
+    target: path.relative(projectPath, targetPath).replace(/\\/g, '/'),
+  };
+}
+
+async function editPrefabJson(projectPath, options = {}) {
+  const target = String(options.target || '').trim();
+  if (!target) {
+    throw new Error('target is required.');
+  }
+  const info = await queryAssetInfo(target);
+  const filePath = assetFilePath(projectPath, info);
+  if (!filePath) {
+    throw new Error(`Prefab file was not found: ${target}`);
+  }
+
+  const original = fs.readFileSync(filePath, 'utf8');
+  let updated = original;
+  if (options.search !== undefined) {
+    const search = String(options.search);
+    if (!search) {
+      throw new Error('search must not be empty.');
+    }
+    if (!original.includes(search)) {
+      throw new Error('search text was not found in prefab file.');
+    }
+    updated = options.replaceAll
+      ? original.split(search).join(String(options.replace || ''))
+      : original.replace(search, String(options.replace || ''));
+  } else {
+    const json = JSON.parse(original);
+    const value = JSON.parse(String(options.valueJson || 'null'));
+    setByJsonPath(json, options.jsonPath, value);
+    updated = JSON.stringify(json, null, 2) + '\n';
+  }
+
+  JSON.parse(updated);
+  if (options.createBackup) {
+    fs.writeFileSync(`${filePath}.bak`, original, 'utf8');
+  }
+  fs.writeFileSync(filePath, updated, 'utf8');
+  return {
+    edited: true,
+    path: path.relative(projectPath, filePath).replace(/\\/g, '/'),
+    oldValue: options.jsonPath ? getByJsonPath(JSON.parse(original), options.jsonPath) : undefined,
+    validation: await validatePrefabReferences(projectPath, { target }),
+  };
+}
+
+async function applyPrefabInstance(nodeUuid) {
+  const uuid = String(nodeUuid || '').trim();
+  if (!uuid) {
+    throw new Error('node uuid is required.');
+  }
+  const result = await requestEditorMessage('scene', 'apply-prefab', uuid);
+  return { applied: true, uuid, result };
+}
+
+async function revertPrefabInstance(nodeUuid) {
+  const uuid = String(nodeUuid || '').trim();
+  if (!uuid) {
+    throw new Error('node uuid is required.');
+  }
+  const candidates = ['revert-prefab', 'restore-prefab'];
+  let lastError = null;
+  for (const method of candidates) {
+    try {
+      const result = await requestEditorMessage('scene', method, uuid);
+      return { reverted: true, uuid, method, result };
+    } catch (error) {
+      lastError = error;
+    }
+  }
+  throw lastError || new Error('No prefab revert editor message was available.');
+}
+
+module.exports = {
+  applyPrefabInstance,
+  duplicatePrefab,
+  editPrefabJson,
+  inspectPrefab,
+  revertPrefabInstance,
+  validatePrefabReferences,
+};
diff --git a/lib/project-instructions.js b/lib/project-instructions.js
new file mode 100644
index 0000000..a20c282
--- /dev/null
+++ b/lib/project-instructions.js
@@ -0,0 +1,155 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const { resolveProjectPath } = require('./path-safety');
+
+const KNOWN_INSTRUCTION_PATHS = [
+  'AGENTS.md',
+  'CLAUDE.md',
+  'GEMINI.md',
+  '.cursorrules',
+  '.windsurfrules',
+  '.github/copilot-instructions.md',
+];
+
+function normalizeSkillName(value) {
+  const normalized = String(value || '')
+    .trim()
+    .toLowerCase()
+    .replace(/[^a-z0-9_-]+/g, '-')
+    .replace(/^-+|-+$/g, '');
+  if (!normalized) {
+    throw new Error('skillName is required.');
+  }
+  return normalized;
+}
+
+function statFile(filePath) {
+  try {
+    return fs.statSync(filePath);
+  } catch (error) {
+    return null;
+  }
+}
+
+function listSkillFiles(projectPath) {
+  const skillRoot = resolveProjectPath(projectPath, '.codex/skills');
+  if (!fs.existsSync(skillRoot)) {
+    return [];
+  }
+
+  const skills = [];
+  const stack = [skillRoot];
+  while (stack.length) {
+    const current = stack.pop();
+    for (const entry of fs.readdirSync(current, { withFileTypes: true })) {
+      const fullPath = path.join(current, entry.name);
+      if (entry.isDirectory()) {
+        stack.push(fullPath);
+        continue;
+      }
+      if (entry.name === 'SKILL.md') {
+        const stat = statFile(fullPath);
+        skills.push({
+          path: path.relative(projectPath, fullPath).replace(/\\/g, '/'),
+          size: stat ? stat.size : 0,
+          mtime: stat ? stat.mtime.toISOString() : '',
+        });
+      }
+    }
+  }
+  return skills.sort((left, right) => left.path.localeCompare(right.path));
+}
+
+function listProjectInstructions(projectPath) {
+  const files = [];
+  for (const relativePath of KNOWN_INSTRUCTION_PATHS) {
+    const fullPath = resolveProjectPath(projectPath, relativePath);
+    const stat = statFile(fullPath);
+    if (stat && stat.isFile()) {
+      files.push({
+        path: relativePath,
+        size: stat.size,
+        mtime: stat.mtime.toISOString(),
+      });
+    }
+  }
+
+  return {
+    files,
+    skills: listSkillFiles(projectPath),
+  };
+}
+
+function readProjectInstruction(projectPath, target) {
+  const relativePath = String(target || '').trim();
+  if (!relativePath) {
+    throw new Error('target is required.');
+  }
+  const fullPath = resolveProjectPath(projectPath, relativePath);
+  if (!fs.existsSync(fullPath) || !fs.statSync(fullPath).isFile()) {
+    throw new Error(`Instruction file not found: ${relativePath}`);
+  }
+  return {
+    path: relativePath,
+    content: fs.readFileSync(fullPath, 'utf8'),
+  };
+}
+
+function writeProjectInstruction(projectPath, options = {}) {
+  const relativePath = String(options.target || '').trim();
+  if (!relativePath) {
+    throw new Error('target is required.');
+  }
+  const content = String(options.content || '');
+  const fullPath = resolveProjectPath(projectPath, relativePath);
+  if (fs.existsSync(fullPath) && options.overwrite === false) {
+    throw new Error(`Instruction file already exists: ${relativePath}`);
+  }
+  fs.mkdirSync(path.dirname(fullPath), { recursive: true });
+  fs.writeFileSync(fullPath, content, 'utf8');
+  const stat = fs.statSync(fullPath);
+  return {
+    written: true,
+    path: relativePath,
+    size: stat.size,
+    mtime: stat.mtime.toISOString(),
+  };
+}
+
+function createProjectSkill(projectPath, options = {}) {
+  const skillName = normalizeSkillName(options.skillName);
+  const title = String(options.title || skillName).trim();
+  const description = String(options.description || `Project-specific workflow for ${title}.`).trim();
+  const body = String(options.instructions || '').trim() || [
+    `Use this skill for ${title} work in this Cocos project.`,
+    '',
+    '- Inspect the active scene and project context before editing.',
+    '- Prefer focused MCP tools before broad manual file edits.',
+    '- Run relevant validation tools after changes.',
+  ].join('\n');
+  const relativePath = `.codex/skills/${skillName}/SKILL.md`;
+  const content = [
+    `# ${title}`,
+    '',
+    `Description: ${description}`,
+    '',
+    '## Instructions',
+    body,
+    '',
+  ].join('\n');
+  return writeProjectInstruction(projectPath, {
+    target: relativePath,
+    content,
+    overwrite: options.overwrite !== false,
+  });
+}
+
+module.exports = {
+  KNOWN_INSTRUCTION_PATHS,
+  createProjectSkill,
+  listProjectInstructions,
+  readProjectInstruction,
+  writeProjectInstruction,
+};
diff --git a/lib/server.js b/lib/server.js
index fb8bddf..a95612a 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -570,10 +570,15 @@ class McpServer {
         }
         return this.createResult(request.id, result);
       } catch (error) {
-        return this.createResult(request.id, {
+        const result = {
           content: textContent(error.message),
           isError: true,
-        });
+        };
+        const structured = structuredContent(error.toolEnvelope);
+        if (structured) {
+          result.structuredContent = structured;
+        }
+        return this.createResult(request.id, result);
       }
     }
 
diff --git a/lib/tool-registry.js b/lib/tool-registry.js
index 83cdd1e..4aecb74 100644
--- a/lib/tool-registry.js
+++ b/lib/tool-registry.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const crypto = require('crypto');
 const fs = require('fs');
 const path = require('path');
 const {
@@ -22,9 +23,24 @@ const {
   searchProjectLogs,
 } = require('./logs');
 const { resolveProjectPath } = require('./path-safety');
+const {
+  createProjectSkill,
+  listProjectInstructions,
+  readProjectInstruction,
+  writeProjectInstruction,
+} = require('./project-instructions');
+const {
+  applyPrefabInstance,
+  duplicatePrefab,
+  editPrefabJson,
+  inspectPrefab,
+  revertPrefabInstance,
+  validatePrefabReferences,
+} = require('./prefabs');
 const { captureDesktopScreenshot, captureEditorWindowScreenshot, capturePanelScreenshot } = require('./screenshots');
 const { checkForUpdate } = require('./update-checker');
 const { safeStringify } = require('./utils');
+const IMAGE_DATA_URI_PREFIX = 'data:image/png;base64,';
 
 const TOOL_CATEGORY_RULES = [
   ['updates', /update/],
@@ -35,6 +51,7 @@ const TOOL_CATEGORY_RULES = [
   ['files', /file|directory|exists|refresh_assets/],
   ['assets', /asset|scene$|scenes|open_scene|run_scene_asset/],
   ['prefabs', /prefab/],
+  ['instructions', /instruction|skill/],
   ['selection', /selection|select_/],
   ['components', /component/],
   ['ui', /canvas|label|button|sprite/],
@@ -57,6 +74,34 @@ function createSchema(properties, required) {
   return schema;
 }
 
+function createOutputSchema(dataSchema = {}) {
+  return {
+    type: 'object',
+    properties: {
+      ok: { type: 'boolean', description: 'Whether the tool call completed successfully.' },
+      tool: { type: 'string', description: 'Tool name that produced this result.' },
+      callId: { type: 'string', description: 'Stable identifier for this tool call result.' },
+      timestamp: { type: 'string', description: 'ISO timestamp when the result envelope was produced.' },
+      summary: { type: 'string', description: 'Short human-readable result summary.' },
+      data: dataSchema,
+      refs: {
+        type: 'array',
+        description: 'Stable references discovered in the result for follow-up tool calls.',
+        items: {
+          type: 'object',
+          properties: {
+            type: { type: 'string' },
+            id: { type: 'string' },
+            path: { type: 'string' },
+            name: { type: 'string' },
+          },
+        },
+      },
+    },
+    required: ['ok', 'tool', 'callId', 'timestamp', 'data'],
+  };
+}
+
 function inferToolCategory(toolName) {
   for (const [category, pattern] of TOOL_CATEGORY_RULES) {
     if (pattern.test(toolName)) {
@@ -86,6 +131,26 @@ function toolCategory(tool) {
   return tool.category || inferToolCategory(tool.name);
 }
 
+function inferToolAnnotations(tool) {
+  const name = tool.name;
+  const category = toolCategory(tool);
+  const readOnly = /^(get|list|inspect|find|read|search|check|validate|exists|capture)/.test(name);
+  const destructive = /(delete|remove|clear|replace|write|reset|set_|execute|run_scene|invoke|emit|simulate)/.test(name);
+  const idempotent = readOnly || /^(set|select|open|pause|resume|stop|refresh)/.test(name);
+
+  return {
+    title: name
+      .split('_')
+      .map((part) => part.charAt(0).toUpperCase() + part.slice(1))
+      .join(' '),
+    readOnlyHint: readOnly,
+    destructiveHint: readOnly ? false : destructive,
+    idempotentHint: idempotent,
+    openWorldHint: category === 'updates',
+    ...(tool.annotations || {}),
+  };
+}
+
 function isToolExposed(config, tool) {
   const profile = config && config.toolProfile === 'full'
     ? 'full'
@@ -112,6 +177,115 @@ function isToolExposed(config, tool) {
   return exposed;
 }
 
+function hashObject(value) {
+  return crypto
+    .createHash('sha256')
+    .update(safeStringify(value))
+    .digest('hex')
+    .slice(0, 16);
+}
+
+function summarizeResult(result) {
+  if (typeof result === 'string') {
+    if (result.startsWith(IMAGE_DATA_URI_PREFIX)) {
+      return 'Image payload returned.';
+    }
+    return result.length > 160 ? `${result.slice(0, 160)}...` : result;
+  }
+  if (!result || typeof result !== 'object') {
+    return String(result);
+  }
+  if (typeof result.summary === 'string') {
+    return result.summary;
+  }
+  for (const key of ['message', 'path', 'url', 'sceneName', 'projectName']) {
+    if (typeof result[key] === 'string' && result[key]) {
+      return `${key}: ${result[key]}`;
+    }
+  }
+  if (Number.isFinite(result.count)) {
+    return `count: ${result.count}`;
+  }
+  return 'Structured result returned.';
+}
+
+function normalizeEnvelopeData(result) {
+  if (typeof result === 'string' && result.startsWith(IMAGE_DATA_URI_PREFIX)) {
+    return {
+      image: true,
+      mimeType: 'image/png',
+      byteLength: Buffer.byteLength(result.slice(IMAGE_DATA_URI_PREFIX.length), 'base64'),
+    };
+  }
+  return result;
+}
+
+function addRef(refs, type, id, extra = {}) {
+  if (!id) {
+    return;
+  }
+  const key = `${type}:${id}`;
+  if (refs.some((ref) => ref.key === key)) {
+    return;
+  }
+  refs.push({ key, type, id: String(id), ...extra });
+}
+
+function collectRefs(value, refs = [], depth = 0, seen = new WeakSet()) {
+  if (!value || depth > 5) {
+    return refs;
+  }
+  if (Array.isArray(value)) {
+    for (const item of value) {
+      collectRefs(item, refs, depth + 1, seen);
+    }
+    return refs;
+  }
+  if (typeof value !== 'object') {
+    return refs;
+  }
+  if (seen.has(value)) {
+    return refs;
+  }
+  seen.add(value);
+
+  const uuid = value.uuid || value.prefabUuid || value.sceneUuid || value.assetUuid;
+  const pathValue = value.path || value.node || value.url;
+  if (uuid) {
+    addRef(refs, pathValue && String(pathValue).startsWith('db://') ? 'asset' : 'uuid', uuid, {
+      path: pathValue ? String(pathValue) : undefined,
+      name: value.name ? String(value.name) : undefined,
+    });
+  }
+  if (typeof pathValue === 'string' && pathValue) {
+    addRef(refs, pathValue.startsWith('db://') ? 'asset' : 'path', pathValue, {
+      name: value.name ? String(value.name) : undefined,
+    });
+  }
+
+  for (const item of Object.values(value)) {
+    collectRefs(item, refs, depth + 1, seen);
+  }
+  return refs;
+}
+
+function createResultEnvelope(tool, args, result, options = {}) {
+  const data = normalizeEnvelopeData(result);
+  const refs = collectRefs(data).map(({ key, ...ref }) => ref);
+  const timestamp = new Date().toISOString();
+  const summary = options.summary || summarizeResult(result);
+  const callId = `fp_${hashObject({ tool: tool.name, args: args || {}, result: data })}`;
+  return {
+    ok: options.ok !== false,
+    tool: tool.name,
+    callId,
+    timestamp,
+    summary,
+    data,
+    refs,
+  };
+}
+
 function summarizeDiagnostics(result) {
   if (!result) {
     return null;
@@ -217,6 +391,17 @@ async function refreshAssets(projectPath, targetPath) {
   return 'File written outside assets directory; no asset-db refresh was needed.';
 }
 
+async function resolveNodeUuid(sceneBridge, args) {
+  if (args && args.uuid) {
+    return String(args.uuid);
+  }
+  const inspected = await sceneBridge.call('inspectNode', args || {});
+  if (!inspected || !inspected.uuid) {
+    throw new Error('Target node uuid could not be resolved.');
+  }
+  return inspected.uuid;
+}
+
 function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runtimeLog, sceneBridge, editorExecutor }) {
   const tools = [
     {
@@ -351,6 +536,67 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
       inputSchema: createSchema({}, []),
       handler: async () => getCurrentSelection(),
     },
+    {
+      name: 'list_project_instructions',
+      profile: 'core',
+      description: '[specialist] List project AI instruction files and local Codex project skills.',
+      inputSchema: createSchema({}, []),
+      handler: async () => {
+        const { projectPath } = getRuntimeContext();
+        return listProjectInstructions(projectPath);
+      },
+    },
+    {
+      name: 'read_project_instruction',
+      profile: 'core',
+      description: '[specialist] Read a project AI instruction file such as AGENTS.md, CLAUDE.md, or a .codex skill SKILL.md.',
+      inputSchema: createSchema(
+        {
+          target: { type: 'string', description: 'Project-relative instruction path.' },
+        },
+        ['target']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        return readProjectInstruction(projectPath, args.target);
+      },
+    },
+    {
+      name: 'write_project_instruction',
+      profile: 'full',
+      description: '[core] Create or update a project AI instruction file inside the Cocos project.',
+      inputSchema: createSchema(
+        {
+          target: { type: 'string', description: 'Project-relative instruction path.' },
+          content: { type: 'string', description: 'Instruction file content.' },
+          overwrite: { type: 'boolean', description: 'Allow overwriting an existing file. Defaults to true.' },
+        },
+        ['target', 'content']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        return writeProjectInstruction(projectPath, args);
+      },
+    },
+    {
+      name: 'create_project_skill',
+      profile: 'full',
+      description: '[core] Create a local Codex project skill under .codex/skills/{skillName}/SKILL.md.',
+      inputSchema: createSchema(
+        {
+          skillName: { type: 'string', description: 'Filesystem-safe project skill name.' },
+          title: { type: 'string', description: 'Human-readable skill title.' },
+          description: { type: 'string', description: 'Skill trigger description.' },
+          instructions: { type: 'string', description: 'Skill instructions body.' },
+          overwrite: { type: 'boolean', description: 'Allow overwriting an existing skill. Defaults to true.' },
+        },
+        ['skillName']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        return createProjectSkill(projectPath, args);
+      },
+    },
     {
       name: 'set_selection',
       profile: 'core',
@@ -537,6 +783,166 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
         return { count: assets.length, prefabs: assets.slice(0, 200) };
       },
     },
+    {
+      name: 'inspect_prefab',
+      profile: 'core',
+      description: '[specialist] Inspect a prefab asset, its metadata, serialized file path, and UUID-like asset references.',
+      inputSchema: createSchema(
+        {
+          target: { type: 'string', description: 'Prefab uuid, db url, or project path.' },
+        },
+        ['target']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        return await inspectPrefab(projectPath, args.target);
+      },
+    },
+    {
+      name: 'validate_prefab_references',
+      profile: 'core',
+      description: '[specialist] Validate prefab asset references by checking serialized UUID references against asset-db.',
+      inputSchema: createSchema(
+        {
+          target: { type: 'string', description: 'Optional prefab uuid, db url, or path. When omitted, scans prefab assets.' },
+          pattern: { type: 'string', description: 'Optional asset-db pattern used when scanning prefabs.' },
+          limit: { type: 'number', description: 'Maximum prefab assets to scan when target is omitted.' },
+        },
+        []
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        return await validatePrefabReferences(projectPath, args);
+      },
+    },
+    {
+      name: 'duplicate_prefab',
+      profile: 'full',
+      description: '[core] Create a new prefab asset by duplicating an existing prefab file without copying its .meta UUID.',
+      inputSchema: createSchema(
+        {
+          source: { type: 'string', description: 'Source prefab uuid, db url, or project path.' },
+          target: { type: 'string', description: 'Project-relative target path under assets, with or without .prefab.' },
+          overwrite: { type: 'boolean', description: 'Overwrite target prefab if it already exists.' },
+        },
+        ['source', 'target']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        const result = await duplicatePrefab(projectPath, args);
+        return { ...result, refresh: await refreshAssets(projectPath, resolveProjectPath(projectPath, result.target)) };
+      },
+    },
+    {
+      name: 'edit_prefab_json',
+      profile: 'full',
+      description: '[core] Edit a prefab JSON file by JSON path assignment or literal search/replace, then validate references.',
+      inputSchema: createSchema(
+        {
+          target: { type: 'string', description: 'Prefab uuid, db url, or project path.' },
+          jsonPath: { type: 'string', description: 'JSON path such as /0/_name or 0._name when assigning valueJson.' },
+          valueJson: { type: 'string', description: 'JSON encoded value to assign at jsonPath.' },
+          search: { type: 'string', description: 'Literal text to search for instead of jsonPath assignment.' },
+          replace: { type: 'string', description: 'Replacement text for literal search.' },
+          replaceAll: { type: 'boolean', description: 'Replace all literal matches.' },
+          createBackup: { type: 'boolean', description: 'Create a .bak file before writing.' },
+        },
+        ['target']
+      ),
+      handler: async (args) => {
+        const { projectPath } = getRuntimeContext();
+        const result = await editPrefabJson(projectPath, args);
+        return { ...result, refresh: await refreshAssets(projectPath, resolveProjectPath(projectPath, result.path)) };
+      },
+    },
+    {
+      name: 'create_prefab_instance',
+      profile: 'full',
+      description: '[core] Create a linked prefab instance in the editor hierarchy using Cocos scene create-node when available.',
+      inputSchema: createSchema(
+        {
+          prefabUuid: { type: 'string', description: 'Prefab asset uuid, db url, or path.' },
+          parentPath: { type: 'string', description: 'Optional parent node path.' },
+          name: { type: 'string', description: 'Optional override node name.' },
+          position: { type: 'object', description: 'Optional position {x,y,z}; fallback runtime path only.' },
+        },
+        ['prefabUuid']
+      ),
+      handler: async (args) => {
+        const info = await queryAssetInfo(args.prefabUuid);
+        const payload = {
+          assetUuid: info.uuid || args.prefabUuid,
+          unlinkPrefab: false,
+        };
+        if (args.parentPath) {
+          payload.parent = await resolveNodeUuid(sceneBridge, { path: args.parentPath });
+        }
+        if (args.name) {
+          payload.name = args.name;
+        }
+
+        if (global.Editor && Editor.Message && typeof Editor.Message.request === 'function') {
+          try {
+            const createdUuid = await Editor.Message.request('scene', 'create-node', payload);
+            return {
+              created: true,
+              linkedPrefab: true,
+              prefabUuid: payload.assetUuid,
+              uuid: createdUuid,
+            };
+          } catch (error) {
+            runtimeLog && runtimeLog.add('warn', `Linked prefab create-node failed: ${error.message}`);
+          }
+        }
+
+        return await sceneBridge.call('instantiatePrefab', {
+          ...args,
+          prefabUuid: info.uuid || args.prefabUuid,
+        });
+      },
+    },
+    {
+      name: 'inspect_prefab_instance',
+      profile: 'core',
+      description: '[specialist] Inspect whether a scene node is linked to a prefab instance and return prefab metadata when available.',
+      inputSchema: createSchema(
+        {
+          path: { type: 'string', description: 'Node hierarchy path.' },
+          uuid: { type: 'string', description: 'Node uuid.' },
+          name: { type: 'string', description: 'Fallback exact node name.' },
+        },
+        []
+      ),
+      handler: async (args) => sceneBridge.call('getPrefabInstanceInfo', args),
+    },
+    {
+      name: 'apply_prefab_instance',
+      profile: 'full',
+      description: '[core] Apply a scene prefab instance back to its associated prefab asset using the Cocos editor scene apply-prefab message.',
+      inputSchema: createSchema(
+        {
+          path: { type: 'string', description: 'Node hierarchy path.' },
+          uuid: { type: 'string', description: 'Node uuid.' },
+          name: { type: 'string', description: 'Fallback exact node name.' },
+        },
+        []
+      ),
+      handler: async (args) => await applyPrefabInstance(await resolveNodeUuid(sceneBridge, args)),
+    },
+    {
+      name: 'revert_prefab_instance',
+      profile: 'full',
+      description: '[core] Revert a scene prefab instance from its associated prefab asset using available Cocos editor prefab revert messages.',
+      inputSchema: createSchema(
+        {
+          path: { type: 'string', description: 'Node hierarchy path.' },
+          uuid: { type: 'string', description: 'Node uuid.' },
+          name: { type: 'string', description: 'Fallback exact node name.' },
+        },
+        []
+      ),
+      handler: async (args) => await revertPrefabInstance(await resolveNodeUuid(sceneBridge, args)),
+    },
     {
       name: 'instantiate_prefab',
       profile: 'full',
@@ -1242,6 +1648,7 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
           includeComponents: true,
         }).catch((error) => ({ ok: false, error: error.message }));
         const runtime = await sceneBridge.call('getRuntimeState', {}).catch((error) => ({ ok: false, error: error.message }));
+        const performance = await sceneBridge.call('getPerformanceSnapshot', {}).catch((error) => ({ ok: false, error: error.message }));
         const diagnostics = args.includeScriptDiagnostics === false
           ? null
           : summarizeDiagnostics(await runScriptDiagnostics(projectPath, args).catch((error) => ({ ok: false, summary: error.message, diagnostics: [] })));
@@ -1250,14 +1657,22 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
           : searchProjectLogs(projectPath, { query: 'error', limit: 20 }).matches;
 
         return {
-          ok: !scene.error && !runtime.error && (!diagnostics || diagnostics.ok) && (!logErrors || logErrors.length === 0),
+          ok: !scene.error && !runtime.error && !performance.error && (!diagnostics || diagnostics.ok) && (!logErrors || logErrors.length === 0),
           scene,
           runtime,
+          performance,
           diagnostics,
           logErrors,
         };
       },
     },
+    {
+      name: 'get_performance_snapshot',
+      profile: 'core',
+      description: '[specialist] Return scene scale and runtime performance-oriented counters such as node/component counts, UI counts, depth, memory, and warnings.',
+      inputSchema: createSchema({}, []),
+      handler: async (args) => sceneBridge.call('getPerformanceSnapshot', args),
+    },
     {
       name: 'get_runtime_state',
       profile: 'core',
@@ -1580,6 +1995,8 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
           name: tool.name,
           description: tool.description,
           inputSchema: tool.inputSchema,
+          outputSchema: tool.outputSchema || createOutputSchema(tool.dataSchema),
+          annotations: inferToolAnnotations(tool),
         }));
     },
     listToolCatalog() {
@@ -1589,6 +2006,8 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
         description: tool.description,
         profile: tool.profile,
         category: toolCategory(tool),
+        annotations: inferToolAnnotations(tool),
+        outputSchema: tool.outputSchema || createOutputSchema(tool.dataSchema),
         enabled: isToolExposed(config || {}, tool),
       }));
     },
@@ -1604,14 +2023,21 @@ function createToolRegistry({ getRuntimeContext, getStatus, interactionLog, runt
 
       try {
         const result = await tool.handler(args || {});
-        const output = toOutput(result);
-        interactionLog.add(name, 'success', output.slice(0, 500));
+        const envelope = createResultEnvelope(tool, args || {}, result);
+        const output = typeof result === 'string' && result.startsWith(IMAGE_DATA_URI_PREFIX)
+          ? result
+          : toOutput(envelope);
+        interactionLog.add(name, 'success', envelope.summary.slice(0, 500));
         return {
-          value: result,
+          value: envelope,
           text: output,
         };
       } catch (error) {
         interactionLog.add(name, 'error', error.message);
+        error.toolEnvelope = createResultEnvelope(tool, args || {}, { message: error.message }, {
+          ok: false,
+          summary: error.message,
+        });
         throw error;
       }
     },
diff --git a/package.json b/package.json
index 5bda709..750b5d2 100644
--- a/package.json
+++ b/package.json
@@ -1,13 +1,13 @@
 {
   "name": "funplay-cocos-mcp",
   "package_version": 2,
-  "version": "0.2.0",
+  "version": "0.3.0",
   "description": "Embedded MCP server for Cocos Creator with scene script execution, project resources, prompts, and file/scene tools.",
   "author": "Funplay",
   "license": "MIT",
   "main": "browser.js",
   "scripts": {
-    "check": "node --check browser.js && node --check scene.js && node --check panel/index.js && node --check lib/assets.js && node --check lib/client-config.js && node --check lib/config.js && node --check lib/diagnostics.js && node --check lib/electron-tools.js && node --check lib/input.js && node --check lib/interaction-log.js && node --check lib/logs.js && node --check lib/path-safety.js && node --check lib/prompts.js && node --check lib/resources.js && node --check lib/runtime-log.js && node --check lib/screenshots.js && node --check lib/server.js && node --check lib/tool-registry.js && node --check lib/update-checker.js && node --check lib/utils.js",
+    "check": "node --check browser.js && node --check scene.js && node --check panel/index.js && node --check lib/assets.js && node --check lib/client-config.js && node --check lib/config.js && node --check lib/diagnostics.js && node --check lib/electron-tools.js && node --check lib/input.js && node --check lib/interaction-log.js && node --check lib/logs.js && node --check lib/path-safety.js && node --check lib/prefabs.js && node --check lib/project-instructions.js && node --check lib/prompts.js && node --check lib/resources.js && node --check lib/runtime-log.js && node --check lib/screenshots.js && node --check lib/server.js && node --check lib/tool-registry.js && node --check lib/update-checker.js && node --check lib/utils.js",
     "test": "node --test"
   },
   "panels": {
diff --git a/scene.js b/scene.js
index efaf521..022d161 100644
--- a/scene.js
+++ b/scene.js
@@ -308,6 +308,97 @@ function findComponentsByClass(componentClass) {
   return results;
 }
 
+function getPrefabInfo(node) {
+  const prefab = node && node._prefab;
+  if (!prefab) {
+    return {
+      linked: false,
+    };
+  }
+
+  const asset = prefab.asset || prefab._asset || null;
+  return {
+    linked: Boolean(asset || prefab.fileId || prefab.root),
+    fileId: prefab.fileId || '',
+    asset: asset
+      ? {
+          name: asset.name || '',
+          uuid: asset.uuid || asset._uuid || '',
+        }
+      : null,
+    instance: prefab.instance ? plain(prefab.instance) : null,
+    sync: prefab.sync,
+    rawKeys: Object.keys(prefab).slice(0, 50),
+  };
+}
+
+function collectSceneStats() {
+  const stats = {
+    nodeCount: 0,
+    activeNodeCount: 0,
+    inactiveNodeCount: 0,
+    maxDepth: 0,
+    componentCount: 0,
+    componentsByType: {},
+    prefabInstanceCount: 0,
+    uiTransformCount: 0,
+    canvasCount: 0,
+    cameraCount: 0,
+    labelCount: 0,
+    spriteCount: 0,
+    buttonCount: 0,
+  };
+
+  function visit(node, depth) {
+    if (node !== getScene()) {
+      stats.nodeCount += 1;
+      stats.maxDepth = Math.max(stats.maxDepth, depth);
+      if (node.active) stats.activeNodeCount += 1;
+      else stats.inactiveNodeCount += 1;
+      if (node._prefab) stats.prefabInstanceCount += 1;
+    }
+
+    for (const component of node.components || []) {
+      const name = component && component.constructor ? component.constructor.name : 'UnknownComponent';
+      stats.componentCount += 1;
+      stats.componentsByType[name] = (stats.componentsByType[name] || 0) + 1;
+      if (component instanceof UITransform) stats.uiTransformCount += 1;
+      if (component instanceof Canvas) stats.canvasCount += 1;
+      if (component instanceof Camera) stats.cameraCount += 1;
+      if (component instanceof Label) stats.labelCount += 1;
+      if (component instanceof Sprite) stats.spriteCount += 1;
+      if (component instanceof Button) stats.buttonCount += 1;
+    }
+
+    for (const child of node.children) {
+      visit(child, depth + 1);
+    }
+  }
+
+  visit(getScene(), 0);
+  return stats;
+}
+
+function buildSceneWarnings(stats) {
+  const warnings = [];
+  if (stats.nodeCount === 0) {
+    warnings.push({ severity: 'warn', code: 'empty_scene', message: 'The active scene has no child nodes.' });
+  }
+  if (stats.cameraCount === 0) {
+    warnings.push({ severity: 'warn', code: 'missing_camera', message: 'No Camera component was found in the active scene.' });
+  }
+  if (stats.nodeCount > 500) {
+    warnings.push({ severity: 'info', code: 'large_node_count', message: `Scene has ${stats.nodeCount} nodes.` });
+  }
+  if (stats.maxDepth > 12) {
+    warnings.push({ severity: 'info', code: 'deep_hierarchy', message: `Scene hierarchy depth is ${stats.maxDepth}.` });
+  }
+  if (stats.labelCount > 80) {
+    warnings.push({ severity: 'info', code: 'many_labels', message: `Scene has ${stats.labelCount} Label components.` });
+  }
+  return warnings;
+}
+
 function getScheduler() {
   return typeof director.getScheduler === 'function' ? director.getScheduler() : null;
 }
@@ -1149,6 +1240,45 @@ exports.methods = {
     };
   },
 
+  async getPerformanceSnapshot() {
+    const scheduler = getScheduler();
+    const stats = collectSceneStats();
+    const memory = typeof performance !== 'undefined' && performance.memory
+      ? {
+          jsHeapSizeLimit: performance.memory.jsHeapSizeLimit,
+          totalJSHeapSize: performance.memory.totalJSHeapSize,
+          usedJSHeapSize: performance.memory.usedJSHeapSize,
+        }
+      : null;
+
+    return {
+      sceneName: getScene().name,
+      runtime: {
+        paused: typeof director.isPaused === 'function' ? director.isPaused() : false,
+        timeScale: scheduler && typeof scheduler.getTimeScale === 'function' ? scheduler.getTimeScale() : 1,
+        totalFrames: typeof director.getTotalFrames === 'function' ? director.getTotalFrames() : undefined,
+      },
+      stats,
+      memory,
+      warnings: buildSceneWarnings(stats),
+    };
+  },
+
+  async getPrefabInstanceInfo(options = {}) {
+    const node = findNode(options);
+    if (!node) {
+      throw new Error('Target node was not found.');
+    }
+    return {
+      node: {
+        name: node.name,
+        path: getNodePath(node),
+        uuid: node.uuid,
+      },
+      prefab: getPrefabInfo(node),
+    };
+  },
+
   async pauseRuntime() {
     if (typeof director.pause === 'function') {
       director.pause();
diff --git a/test/project-instructions.test.js b/test/project-instructions.test.js
new file mode 100644
index 0000000..bee2ba1
--- /dev/null
+++ b/test/project-instructions.test.js
@@ -0,0 +1,48 @@
+'use strict';
+
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+const test = require('node:test');
+const {
+  createProjectSkill,
+  listProjectInstructions,
+  readProjectInstruction,
+  writeProjectInstruction,
+} = require('../lib/project-instructions');
+
+test('project instruction helpers list, read, and write safe project files', () => {
+  const projectPath = fs.mkdtempSync(path.join(os.tmpdir(), 'funplay-cocos-instructions-'));
+  const write = writeProjectInstruction(projectPath, {
+    target: 'AGENTS.md',
+    content: '# Agent Notes\n',
+  });
+
+  assert.equal(write.written, true);
+  assert.equal(readProjectInstruction(projectPath, 'AGENTS.md').content, '# Agent Notes\n');
+
+  const listed = listProjectInstructions(projectPath);
+  assert.equal(listed.files.some((file) => file.path === 'AGENTS.md'), true);
+});
+
+test('createProjectSkill writes a Codex project skill', () => {
+  const projectPath = fs.mkdtempSync(path.join(os.tmpdir(), 'funplay-cocos-skill-'));
+  const result = createProjectSkill(projectPath, {
+    skillName: 'scene qa',
+    title: 'Scene QA',
+    description: 'Validate Cocos scenes.',
+  });
+
+  assert.equal(result.path, '.codex/skills/scene-qa/SKILL.md');
+  const listed = listProjectInstructions(projectPath);
+  assert.equal(listed.skills.some((skill) => skill.path === result.path), true);
+});
+
+test('project instruction helpers reject traversal outside the project', () => {
+  const projectPath = fs.mkdtempSync(path.join(os.tmpdir(), 'funplay-cocos-instructions-safe-'));
+  assert.throws(
+    () => writeProjectInstruction(projectPath, { target: '../AGENTS.md', content: 'x' }),
+    /outside the Cocos project/
+  );
+});
diff --git a/test/tool-registry.test.js b/test/tool-registry.test.js
index e82fa6d..ab98f52 100644
--- a/test/tool-registry.test.js
+++ b/test/tool-registry.test.js
@@ -5,7 +5,7 @@ const path = require('node:path');
 const test = require('node:test');
 const { createToolRegistry } = require('../lib/tool-registry');
 
-function createRegistry(profile, projectPath = path.resolve('/tmp/funplay-cocos-test-project'), configExtras = {}) {
+function createRegistry(profile, projectPath = path.resolve('/tmp/funplay-cocos-test-project'), configExtras = {}, overrides = {}) {
   return createToolRegistry({
     getRuntimeContext: () => ({
       config: { toolProfile: profile, ...configExtras },
@@ -13,31 +13,42 @@ function createRegistry(profile, projectPath = path.resolve('/tmp/funplay-cocos-
       version: '0.0.0-test',
     }),
     interactionLog: { add() {} },
-    runtimeLog: { list: () => [], clear: () => 0 },
-    sceneBridge: { call: async () => ({ ok: true }) },
-    editorExecutor: async () => ({ ok: true }),
+    runtimeLog: { add() {}, list: () => [], clear: () => 0 },
+    sceneBridge: overrides.sceneBridge || { call: async () => ({ ok: true }) },
+    editorExecutor: overrides.editorExecutor || (async () => ({ ok: true })),
   });
 }
 
 test('core profile exposes the documented focused tool set', () => {
   const tools = createRegistry('core').listTools();
-  assert.equal(tools.length, 28);
+  assert.equal(tools.length, 34);
   assert.equal(tools.some((tool) => tool.name === 'execute_javascript'), true);
   assert.equal(tools.some((tool) => tool.name === 'get_editor_state'), true);
   assert.equal(tools.some((tool) => tool.name === 'get_tool_catalog'), true);
   assert.equal(tools.some((tool) => tool.name === 'validate_scene'), true);
+  assert.equal(tools.some((tool) => tool.name === 'get_performance_snapshot'), true);
+  assert.equal(tools.some((tool) => tool.name === 'list_project_instructions'), true);
   assert.equal(tools.some((tool) => tool.name === 'set_selection'), true);
   assert.equal(tools.some((tool) => tool.name === 'write_file'), false);
 });
 
 test('full profile exposes all built-in tools', () => {
   const tools = createRegistry('full').listTools();
-  assert.equal(tools.length, 76);
+  assert.equal(tools.length, 89);
   assert.equal(tools.some((tool) => tool.name === 'write_file'), true);
+  assert.equal(tools.some((tool) => tool.name === 'edit_prefab_json'), true);
+  assert.equal(tools.some((tool) => tool.name === 'create_project_skill'), true);
   assert.equal(tools.some((tool) => tool.name === 'get_editor_state'), true);
   assert.equal(tools.some((tool) => tool.name === 'set_selection'), true);
 });
 
+test('tool definitions include MCP outputSchema and annotations', () => {
+  const tool = createRegistry('core').listTools().find((item) => item.name === 'get_project_info');
+  assert.equal(tool.outputSchema.type, 'object');
+  assert.equal(tool.outputSchema.properties.ok.type, 'boolean');
+  assert.equal(tool.annotations.readOnlyHint, true);
+});
+
 test('custom profile can expose a category and disable a specific tool', () => {
   const tools = createRegistry('custom', path.resolve('/tmp/funplay-cocos-test-project'), {
     enabledToolCategories: ['files'],
@@ -69,6 +80,21 @@ test('file tools reject writes outside the project root', async () => {
 test('callToolDetailed preserves structured values and text output', async () => {
   const registry = createRegistry('core');
   const result = await registry.callToolDetailed('get_project_info', {});
-  assert.equal(result.value.projectPath, path.resolve('/tmp/funplay-cocos-test-project'));
+  assert.equal(result.value.ok, true);
+  assert.equal(result.value.tool, 'get_project_info');
+  assert.equal(result.value.data.projectPath, path.resolve('/tmp/funplay-cocos-test-project'));
+  assert.match(result.value.callId, /^fp_/);
   assert.match(result.text, /projectPath/);
 });
+
+test('callToolDetailed preserves screenshot image text while keeping structured envelope small', async () => {
+  const dataUri = 'data:image/png;base64,AAAA';
+  const registry = createRegistry('core', path.resolve('/tmp/funplay-cocos-test-project'), {}, {
+    editorExecutor: async () => dataUri,
+  });
+
+  const result = await registry.callToolDetailed('execute_javascript', { context: 'editor', code: 'return image;' });
+  assert.equal(result.text, dataUri);
+  assert.equal(result.value.data.image, true);
+  assert.equal(result.value.data.mimeType, 'image/png');
+});