unity

Unity MCP Server provides a Node-based MCP bridge that lets LLM clients automate the Unity Editor via a JSON-RPC interface over TCP. The server exposes a large catalog of tools for editor automation, UI interaction, input simulation, visual capture, code-base awareness, project settings, and Addressables management. By default, the server starts a TCP listener on port 6400 and is designed to be used with Claude Desktop or other MCP-compatible clients. You can also run in HTTP mode for restricted networks. To use it, start the server with an npx command (as shown in the installation section), then configure your MCP client to connect to the host and port exposed by the server. Use the provided tool discovery and filtering options to find the right tool for tasks like scene creation, GameObject manipulation, or taking deterministic screenshots from Unity views.

Once connected, you can query available tools, execute tool actions via JSON-RPC, and inspect responses. If you need HTTP-only access, the server can be started in HTTP mode which exposes REST-like endpoints in addition to the MCP JSON-RPC channel. The tooling includes a large set of Unity-specific operations, such as scene and prefab edits, input simulation for playmode testing, and Addressables management, all designed to work in headless or automated workflows. The documentation also notes capabilities for code navigation and editing via a bundled C# LSP layer, enabling safer symbol/search operations against the Unity project assets.

Prerequisites:

• Node.js 18.x, 20.x, 22.x, or 24.x LTS (25+ not supported)
• npm or yarn
• Unity installed for editor automation (Unity 2020.3 LTS or newer)
• Access to the Unity package (via Git URL or npm/OpenUPM as described below)

Installation steps:

1. Install via npx (recommended for quick start):

npx @akiojin/unity-mcp-server@latest --http 6401 --no-telemetry

This starts the MCP server in HTTP-enabled mode on port 6401 (remove --http flag to use TCP on 6400).

2. If you prefer using a package manager in Unity, follow the Unity Package section in the README to install the unity-mcp-server package into your Unity project and then run the Node server separately as above.

3. Configure your MCP client (Claude Desktop example):

{
  "mcpServers": {
    "unity-mcp-server": {
      "command": "npx",
      "args": ["@akiojin/unity-mcp-server@latest"]
    }
  }
}

Save this to your client’s configuration file (the path depends on your platform as described in the README).

4. Start Unity and ensure the TCP listener on port 6400 is open (or use HTTP mode as shown). Then connect your MCP client to the server and begin issuing tool requests.

Notes and tips:

• This MCP server is marked as deprecated in the README; development has moved to akiojin/unity-cli, so consider evaluating the successor project for long-term use.
• Server defaults: Unity-focused tooling, 100+ tools, and code-index capabilities for fast symbol/reference searches.
• Environment variables can tune tool visibility and filtering. Example: export UNITY_MCP_TOOL_INCLUDE_CATEGORIES=system,scene,gameobject,analysis,script
• Ports to know: 6400 for TCP, 6401 for HTTP mode (example shown in the installation steps).
• If you encounter connectivity issues, verify Unity is running and the TCP listener is active, then confirm the MCP client is configured to the correct port and address.
• The configuration supports optional environment-based setup on the Node side; Unity-side configuration is handled within the Unity project settings.