MCP Game Deck

Give Claude Code full control over the Unity Editor.

268 MCP Tools  ·  7 Resources  ·  5 Prompts  ·  10 Agents  ·  18 Slash Commands  ·  16-doc Knowledge Base

v1.0.1  •  Unity 6+  •  MCP Protocol  •  Requires Claude Code & Node.js

What is MCP Game Deck?

MCP Game Deck is a Unity Editor package that exposes your entire project to Claude Code through the Model Context Protocol (MCP). It is not an AI itself — it is the bridge that lets Claude Code see, create, modify, and inspect everything in your Unity Editor: scenes, GameObjects, prefabs, materials, scripts, builds, and more.

How it works: The package runs a custom MCP server inside the Unity Editor. Claude Code connects to it and gains access to 268 tools that control the editor. You talk to Claude Code, Claude Code talks to your Unity project.

What's included:

• MCP Server — A custom C# HTTP server with 268 tools, 7 resources, and 5 prompts. Runs inside the Editor process. No external MCP libraries.
• Intelligence Layer — 10 specialized agents, 18 slash commands, and a 16-document knowledge base that give Claude Code deep Unity domain expertise.
• Chat UI — An optional EditorWindow (powered by Claude Agent SDK + Node.js) for chatting with Claude directly inside Unity.

Features

268 MCP Tools

Full programmatic control over the Unity Editor, organized into 37 categories:

7 MCP Resources

Read-only access to live project state:

5 Workflow Prompts

Structured templates for common multi-step workflows:

• build-pipeline — Configure and execute single or multi-platform builds
• gameobject-handling-strategy — Best practices for creating and organizing GameObjects
• prefab-workflow — Prefab creation, editing, and management
• scene-setup — Scene organization with proper lighting, camera, and structure
• ui-toolkit-workflow — UI Toolkit patterns with UXML, USS, and C# backing

10 Specialized AI Agents

Domain experts with deep knowledge and access to all MCP tools:

18 Slash Commands

Quick-access structured workflows:

16-Document Knowledge Base

Comprehensive Unity reference documentation covering:

Getting Started

Prerequisites

• Claude Code — This package is designed to work with Claude Code. Install Claude Code
• Unity 6 (6000.0 or later)
• Node.js 18+ (required for the Agent SDK Server and Chat UI)
• Claude API key (for Claude Code and the integrated Chat UI)

Installation

1. Clone or download this repository

2. In Unity, go to Window > Package Manager

3. Click + > Add package from disk...

4. Select the package.json at the root of this repository

5. Build the Agent SDK Server:

   cd Server~
   npm install
   npm run build
   

6. On first import, the package automatically copies .claude/, knowledge-base/, and CLAUDE.md to your project root

First Launch

The MCP server starts automatically when the Unity Editor loads. To use the integrated chat:

1. Open Window > MCP Game Deck Chat
2. The Agent SDK server starts automatically (or run npm start in Server~/)
3. Start chatting — Claude now has full access to your Unity project

To use with Claude Code CLI instead:

1. Navigate to your Unity project root
2. Run claude — the CLAUDE.md instructs Claude on available tools
3. Claude will connect to the MCP server on port 8090

How It Works

Unity Editor
 |
 |-- MCP Server (C# HTTP, port 8090)
 |    |-- 268 Tools ......... create, modify, inspect editor state
 |    |-- 7 Resources ....... read-only project data
 |    '-- 5 Prompts ......... structured workflow templates
 |
 |-- Chat UI (EditorWindow, UI Toolkit)
 |    '-- WebSocket client -> Agent SDK Server
 |
 '-- Agent SDK Server (Node.js, port 9100)
      |-- Claude API integration
      |-- MCP proxy -> forwards tool calls to C# server
      '-- Session management & cost tracking

The MCP server runs inside the Unity Editor process with zero external dependencies. All tool calls that touch Unity APIs execute on the main thread via an internal dispatcher. The server automatically stops during assembly reload and play mode transitions.

Configuration

Settings are stored in ProjectSettings/GameDeckSettings.json and editable via Project Settings > MCP Game Deck.

Project Structure

mcp-game-deck/
|-- package.json              Unity package manifest
|-- CLAUDE.md                 AI context file (copied to user project)
|-- README.md                 This file
|
|-- Editor/                   C# editor-only code
|    |-- MCP/                 Custom MCP framework
|    |    |-- Attributes/     [McpTool], [McpToolType], [McpResource], [McpPrompt]
|    |    |-- Models/         ToolResponse, ResourceResponse, McpToolInfo
|    |    |-- Discovery/      Reflection-based tool/resource/prompt discovery
|    |    |-- Registry/       In-memory registries for tools, resources, prompts
|    |    |-- Server/         TCP/HTTP server, JSON-RPC 2.0 handler
|    |    '-- Utils/          MainThreadDispatcher, JsonHelper, McpLogger
|    |-- Tools/               268 MCP tools (37 categories)
|    |-- Resources/           7 MCP resources
|    |-- Prompts/             5 MCP prompts
|    |-- ChatUI/              Integrated chat EditorWindow
|    |-- Settings/            Project settings UI and persistence
|    '-- Utils/               PackageSetup, helpers
|
|-- Server~/                  Agent SDK Server (TypeScript, ~ = ignored by Unity)
|    |-- src/                 Source files
|    |-- dist/                Compiled output
|    '-- package.json         Node.js dependencies
|
|-- .claude/                  AI intelligence layer
|    |-- agents/              10 specialized agent definitions
|    '-- skills/              18 slash command definitions
|
'-- knowledge-base/           16 Unity reference documents

Requirements

License

This project is licensed under the MIT License.

Author

Ramon Bedin — GitHub

MCP Game Deck v1.0
Built for Unity 6  •  Powered by MCP  •  Designed by Ramon Bedin