unity-mcp

Proudly sponsored and maintained by Coplay -- the best AI assistant for Unity. Read the backstory here.

Create your Unity apps with LLMs!

MCP for Unity acts as a bridge, allowing AI assistants (like Claude, Cursor) to interact directly with your Unity Editor via a local MCP (Model Context Protocol) Client. Give your LLM tools to manage assets, control scenes, edit scripts, and automate tasks within Unity.

💬 Join Our Discord

Get help, share ideas, and collaborate with other MCP for Unity developers!

Key Features 🚀

• 🗣️ Natural Language Control: Instruct your LLM to perform Unity tasks.
• 🛠️ Powerful Tools: Manage assets, scenes, materials, scripts, and editor functions.
• 🤖 Automation: Automate repetitive Unity workflows.
• 🧩 Extensible: Designed to work with various MCP Clients.

How It Works

MCP for Unity connects your tools using two components:

1. MCP for Unity Bridge: A Unity package running inside the Editor. (Installed via Package Manager).
2. MCP for Unity Server: A Python server that runs locally, communicating between the Unity Bridge and your MCP Client. (Installed automatically by the package on first run or via Auto-Setup; manual setup is available as a fallback).

Installation ⚙️

Prerequisites

• Python: Version 3.12 or newer. Download Python

• Unity Hub & Editor: Version 2021.3 LTS or newer. Download Unity

• uv (Python toolchain manager):

  # macOS / Linux
  curl -LsSf https://astral.sh/uv/install.sh | sh
  
  # Windows (PowerShell)
  winget install Astral.Sh.Uv
  
  # Docs: https://docs.astral.sh/uv/getting-started/installation/
  

• An MCP Client: : Claude Desktop | Claude Code | Cursor | Visual Studio Code Copilot | Windsurf | Others work with manual config

• [Optional] Roslyn for Advanced Script Validation

  For Strict validation level that catches undefined namespaces, types, and methods:

  Method 1: NuGet for Unity (Recommended)

  1. Install NuGetForUnity
  2. Go to Window > NuGet Package Manager
  3. Search for Microsoft.CodeAnalysis.CSharp and install the package
  4. Go to Player Settings > Scripting Define Symbols
  5. Add USE_ROSLYN
  6. Restart Unity

  Method 2: Manual DLL Installation

  1. Download Microsoft.CodeAnalysis.CSharp.dll and dependencies from NuGet
  2. Place DLLs in Assets/Plugins/ folder
  3. Ensure .NET compatibility settings are correct
  4. Add USE_ROSLYN to Scripting Define Symbols
  5. Restart Unity

  Note: Without Roslyn, script validation falls back to basic structural checks. Roslyn enables full C# compiler diagnostics with precise error reporting.

🌟 Step 1: Install the Unity Package

To install via Git URL

1. Open your Unity project.
2. Go to Window > Package Manager.
3. Click + -> Add package from git URL....
4. Enter:

   https://github.com/CoplayDev/unity-mcp.git?path=/UnityMcpBridge
   

5. Click Add.
6. The MCP server is installed automatically by the package on first run or via Auto-Setup. If that fails, use Manual Configuration (below).

To install via OpenUPM

1. Install the OpenUPM CLI
2. Open a terminal (PowerShell, Terminal, etc.) and navigate to your Unity project directory
3. Run openupm add com.coplaydev.unity-mcp

Note: If you installed the MCP Server before Coplay's maintenance, you will need to uninstall the old package before re-installing the new one.

🛠️ Step 2: Configure Your MCP Client

Connect your MCP Client (Claude, Cursor, etc.) to the Python server set up in Step 1 (auto) or via Manual Configuration (below).

Option A: Auto-Setup (Recommended for Claude/Cursor/VSC Copilot)

1. In Unity, go to Window > MCP for Unity.
2. Click Auto-Setup.
3. Look for a green status indicator 🟢 and "Connected ✓". (This attempts to modify the MCP Client's config file automatically).

Option B: Manual Configuration

If Auto-Setup fails or you use a different client:

1. Find your MCP Client's configuration file. (Check client documentation).
   • Claude Example (macOS): ~/Library/Application Support/Claude/claude_desktop_config.json
   • Claude Example (Windows): %APPDATA%\Claude\claude_desktop_config.json
2. Edit the file to add/update the mcpServers section, using the exact paths from Step 1.

claude mcp add UnityMCP -- uv --directory /Users/USERNAME/Library/AppSupport/UnityMCP/UnityMcpServer/src run server.py

claude mcp add UnityMCP -- "C:/Users/USERNAME/AppData/Local/Microsoft/WinGet/Links/uv.exe" --directory "C:/Users/USERNAME/AppData/Local/UnityMCP/UnityMcpServer/src" run server.py

{
  "servers": {
    "unityMCP": {
      "command": "uv",
      "args": ["--directory","<ABSOLUTE_PATH_TO>/UnityMcpServer/src","run","server.py"],
      "type": "stdio"
    }
  }
}

{
  "mcpServers": {
    "UnityMCP": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "C:\\Users\\YOUR_USERNAME\\AppData\\Local\\UnityMCP\\UnityMcpServer\\src",
        "server.py"
      ]
    }
    // ... other servers might be here ...
  }
}

{
  "mcpServers": {
    "UnityMCP": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "/Users/YOUR_USERNAME/Library/AppSupport/UnityMCP/UnityMcpServer/src",
        "server.py"
      ]
    }
    // ... other servers might be here ...
  }
}

{
  "mcpServers": {
    "UnityMCP": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "/home/YOUR_USERNAME/.local/share/UnityMCP/UnityMcpServer/src",
        "server.py"
      ]
    }
    // ... other servers might be here ...
  }
}

Usage ▶️

1. Open your Unity Project. The MCP for Unity package should connect automatically. Check status via Window > MCP for Unity.

2. Start your MCP Client (Claude, Cursor, etc.). It should automatically launch the MCP for Unity Server (Python) using the configuration from Installation Step 2.

3. Interact! Unity tools should now be available in your MCP Client.

   Example Prompt: Create a 3D player controller, Create a tic-tac-toe game in 3D, Create a cool shader and apply to a cube.

Development & Contributing 🛠️

For Developers

If you're contributing to MCP for Unity or want to test core changes, we have development tools to streamline your workflow:

• Development Deployment Scripts: Quickly deploy and test your changes to MCP for Unity Bridge and Python Server
• Automatic Backup System: Safe testing with easy rollback capabilities
• Hot Reload Workflow: Fast iteration cycle for core development

📖 See README-DEV.md for complete development setup and workflow documentation.

Contributing 🤝

Help make MCP for Unity better!

1. Fork the main repository.
2. Create a branch (feature/your-idea or bugfix/your-fix).
3. Make changes.
4. Commit (feat: Add cool new feature).
5. Push your branch.
6. Open a Pull Request against the main branch.

Troubleshooting ❓

Still stuck? Open an Issue or Join the Discord!

License 📜

MIT License. See LICENSE file.

Star History

Sponsor