Unity MCP Ghost

Unity MCP Ghost is a Cursor-first Unity automation bridge inspired by the Unreal MCP Ghost architecture: inspect, mutate, validate, repair, test, and document Unity projects through deterministic MCP tools.

This repository currently contains the initial project scaffold:

• server/ - TypeScript MCP server, tool registry, Unity bridge client, and stdio transport entry point.
• Packages/com.crispywonton.unity-mcp-ghost/ - Unity UPM editor bridge package skeleton.
• docs/ - architecture and development notes for the Ghost roadmap.

Goals

• Expose safe Unity Editor workflows to MCP clients such as Cursor.
• Route Unity state changes through Unity editor APIs rather than direct file edits.
• Wrap mutating operations in Undo groups where possible.
• Return structured JSON for reliable follow-up tool calls.
• Build toward diagnostics, repair loops, tests, screenshots, and knowledge-base guided workflows.

Early Local Flow

1. Open a Unity project that has Packages/com.crispywonton.unity-mcp-ghost installed.
2. Start the Unity bridge from Window > Unity MCP Ghost.
3. Run the MCP server from this repo:

npm install
npm run build
node dist/index.js --transport stdio --unity-host 127.0.0.1 --unity-port 6400

Cursor MCP Config

{
  "mcpServers": {
    "unity-mcp-ghost": {
      "command": "node",
      "args": [
        "C:/Dev/Unity-MCP-Ghost/server/dist/index.js",
        "--transport",
        "stdio",
        "--unity-host",
        "127.0.0.1",
        "--unity-port",
        "6400"
      ]
    }
  }
}

Current Status

This is a brand-new project scaffold. The first implementation target is the Phase 1/2 vertical slice:

• MCP ping
• Unity connection health
• editor state
• console logs
• scene hierarchy
• create GameObject
• set transform
• save scene
• screenshot capture