MCP Unity Editor (Game Engine)

                              ,/(/.   *(/,                                  
                          */(((((/.   *((((((*.                             
                     .*((((((((((/.   *((((((((((/.                         
                 ./((((((((((((((/    *((((((((((((((/,                     
             ,/(((((((((((((/*.           */(((((((((((((/*.                
            ,%%#((/((((((*                    ,/(((((/(#&@@(                
            ,%%##%%##((((((/*.             ,/((((/(#&@@@@@@(                
            ,%%######%%##((/(((/*.    .*/(((//(%@@@@@@@@@@@(                
            ,%%####%#(%%#%%##((/((((((((//#&@@@@@@&@@@@@@@@(                
            ,%%####%(    /#%#%%%##(//(#@@@@@@@%,   #@@@@@@@(                
            ,%%####%(        *#%###%@@@@@@(        #@@@@@@@(                
            ,%%####%(           #%#%@@@@,          #@@@@@@@(                
            ,%%##%%%(           #%#%@@@@,          #@@@@@@@(                
            ,%%%#*              #%#%@@@@,             *%@@@(                
            .,      ,/##*.      #%#%@@@@,     ./&@#*      *`                
                ,/#%#####%%#/,  #%#%@@@@, ,/&@@@@@@@@@&\.                    
                 `*#########%%%%###%@@@@@@@@@@@@@@@@@@&*´                   
                    `*%%###########%@@@@@@@@@@@@@@&*´                        
                        `*%%%######%@@@@@@@@@@&*´                            
                            `*#%%##%@@@@@&*´                                 
                               `*%#%@&*´                                     
                                                       
     ███╗   ███╗ ██████╗██████╗         ██╗   ██╗███╗   ██╗██╗████████╗██╗   ██╗
     ████╗ ████║██╔════╝██╔══██╗        ██║   ██║████╗  ██║██║╚══██╔══╝╚██╗ ██╔╝
     ██╔████╔██║██║     ██████╔╝        ██║   ██║██╔██╗ ██║██║   ██║    ╚████╔╝ 
     ██║╚██╔╝██║██║     ██╔═══╝         ██║   ██║██║╚██╗██║██║   ██║     ╚██╔╝  
     ██║ ╚═╝ ██║╚██████╗██║             ╚██████╔╝██║ ╚████║██║   ██║      ██║   
     ╚═╝     ╚═╝ ╚═════╝╚═╝              ╚═════╝ ╚═╝  ╚═══╝╚═╝   ╚═╝      ╚═╝   

MCP Unity is an implementation of the Model Context Protocol for Unity Editor, allowing AI assistants to interact with your Unity projects. This package provides a bridge between Unity and a Node.js server that implements the MCP protocol, enabling AI agents like Claude, Windsurf, and Cursor to execute operations within the Unity Editor.

Features

IDE Integration - Package Cache Access

MCP Unity provides automatic integration with VSCode-like IDEs (Visual Studio Code, Cursor, Windsurf) by adding the Unity Library/PackedCache folder to your workspace. This feature:

• Improves code intelligence for Unity packages
• Enables better autocompletion and type information for Unity packages
• Helps AI coding assistants understand your project's dependencies

MCP Server Tools

• execute_menu_item: Executes Unity menu items (functions tagged with the MenuItem attribute)

  Example prompt: "Execute the menu item 'GameObject/Create Empty' to create a new empty GameObject"

• select_gameobject: Selects game objects in the Unity hierarchy by path or instance ID

  Example prompt: "Select the Main Camera object in my scene"

• update_component: Updates component fields on a GameObject or adds it to the GameObject if it does not contain the component

  Example prompt: "Add a Rigidbody component to the Player object and set its mass to 5"

• add_package: Installs new packages in the Unity Package Manager

  Example prompt: "Add the TextMeshPro package to my project"

• run_tests: Runs tests using the Unity Test Runner

  Example prompt: "Run all the EditMode tests in my project"

• notify_message: Displays messages in the Unity Editor

  Example prompt: "Send a notification to Unity that the task has been completed"

• add_asset_to_scene: Adds an asset from the AssetDatabase to the Unity scene

  Example prompt: "Add the Player prefab from my project to the current scene"

MCP Server Resources

• unity://menu-items: Retrieves a list of all available menu items in the Unity Editor to facilitate execute_menu_item tool

  Example prompt: "Show me all available menu items related to GameObject creation"

• unity://hierarchy: Retrieves a list of all game objects in the Unity hierarchy

  Example prompt: "Show me the current scene hierarchy structure"

• unity://gameobject/{id}: Retrieves detailed information about a specific GameObject by instance ID or object path in the scene hierarchy, including all GameObject components with it's serialized properties and fields

  Example prompt: "Get me detailed information about the Player GameObject"

• unity://logs: Retrieves a list of all logs from the Unity console

  Example prompt: "Show me the recent error messages from the Unity console"

• unity://packages: Retrieves information about installed and available packages from the Unity Package Manager

  Example prompt: "List all the packages currently installed in my Unity project"

• unity://assets: Retrieves information about assets in the Unity Asset Database

  Example prompt: "Find all texture assets in my project"

• unity://tests/{testMode}: Retrieves information about tests in the Unity Test Runner

  Example prompt: "List all available tests in my Unity project"

Requirements

• Unity 2022.3 or later - to install the server
• Node.js 18 or later - to start the server
• npm 9 or later - to debug the server

Installation

Installing this MCP Unity Server is a multi-step process:

Step 1: Install Unity MCP Server package via Unity Package Manager

1. Open the Unity Package Manager (Window > Package Manager)
2. Click the "+" button in the top-left corner
3. Select "Add package from git URL..."
4. Enter: https://github.com/CoderGamester/mcp-unity.git
5. Click "Add"

Step 2: Install Node.js

To run MCP Unity server, you'll need to have Node.js 18 or later installed on your computer:

Step 3: Configure AI LLM Client

{
   "mcpServers": {
       "mcp-unity": {
          "command": "node",
          "args": [
             "ABSOLUTE/PATH/TO/mcp-unity/Server/build/index.js"
          ]
       }
   }
}

Start Unity Editor MCP Server

1. Open the Unity Editor
2. Navigate to Tools > MCP Unity > Server Window
3. Click "Start Server" to start the WebSocket server
4. Open Claude Desktop or your AI Coding IDE (e.g. Cursor IDE, Windsurf IDE, etc.) and start executing Unity tools

When the AI client connects to the WebSocket server, it will automatically show in the green box in the window

Optional: Set WebSocket Port

By default, the WebSocket server runs on port 8090. You can change this port in two ways:

Debugging the Server

npx @modelcontextprotocol/inspector node Server/build/index.js

npx @modelcontextprotocol/inspector node Server/build/index.js

Troubleshooting

Support & Feedback

If you have any questions or need support, please open an issue on this repository.

Alternative you can reach out on:

• Linkedin:
• Discord: gamester7178
• Email: game.gamester@gmail.com

Contributing

Contributions are welcome! Please feel free to submit a Pull Request or open an Issue with your request.

Commit your changes following the Conventional Commits format.

License

This project is under MIT License

Acknowledgements

• Model Context Protocol
• Unity Technologies
• Node.js
• WebSocket-Sharp