@yuki-is-taka/uemcp

stdio MCP server that bridges Claude Code to running Unreal Engine editors via the UEMCP plugin. Handles auto-discovery of running editors, transparent reconnect on editor restart, and natural-language editor selection across multiple running projects.

Installation

# Global install (recommended)
npm install -g @yuki-is-taka/uemcp

# Or let Claude Code pull it on demand via npx

Claude Code configuration

~/.claude/settings.json (or per-project .mcp.json):

{
  "mcpServers": {
    "unreal": {
      "type": "stdio",
      "command": "uemcp"
    }
  }
}

Or without global install:

{
  "mcpServers": {
    "unreal": {
      "type": "stdio",
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@yuki-is-taka/uemcp"]
    }
  }
}

How it works

The shim watches a discovery directory for *.json files written by each running UEMCP plugin instance:

Windows: %LOCALAPPDATA%/UnrealMcp/instances/
macOS:   ~/Library/Application Support/UnrealMcp/instances/
Linux:   $XDG_STATE_HOME/UnrealMcp/instances/

When Claude Code calls a tool, the shim routes it to the right editor based on the editor? argument (fuzzy project-name match), or to the session default, or to the only running one if unambiguous.

Development

This package is developed in the uemcp-dev monorepo.

git clone https://github.com/yuki-is-taka/uemcp-dev.git
cd uemcp-dev/shim
npm install
npm run build
npm link