Chess MCP Server

# Chess MCP Server A Model Context Protocol (MCP) server that provides a chess-playing environment backed by the Stockfish engine. Designed for use with LLM clients (like Claude Desktop) to ensure all chess moves are legal and engine-calculated. ## Features - **Legal Move Validation**: All moves are validated against chess rules - **Stockfish Integration**: Uses the Stockfish chess engine for AI moves - **MCP Protocol**: Communicates via JSON-RPC over stdio - **In-Memory Game State**: Maintains multiple concurrent games ## Installation ```bash pip install chess-mcp ``` You'll also need to install Stockfish: - **Windows**: Download from [Stockfish website](https://stockfishchess.org/download/) - **macOS**: `brew install stockfish` - **Linux**: `sudo apt install stockfish` (or equivalent) ## Usage 1. Set the `STOCKFISH_PATH` environment variable to the path of your Stockfish executable: ```bash export STOCKFISH_PATH=/path/to/stockfish ``` 2. Run the server: ```bash python -m chess_mcp ``` ## MCP Tools ### `new_game()` Starts a new chess game from the standard initial position. **Returns:** - `game_id`: Unique identifier for the game - `fen`: Current position in FEN notation - `legal_moves`: List of all legal moves in UCI format ### `make_move(game_id, move_uci)` Applies a human move to the game. The move must be in UCI format (e.g., "e2e4"). **Parameters:** - `game_id`: Identifier of the active game - `move_uci`: Move in UCI format **Returns:** - `ok`: Whether the move was legal and applied - `fen`: Updated board position (if move was legal) - `legal_moves`: Updated list of legal moves ### `engine_move(game_id, depth=14)` Asks Stockfish to calculate and play one move for the side to move. **Parameters:** - `game_id`: Identifier of the active game - `depth`: Search depth for Stockfish (higher = stronger but slower) **Returns:** - `engine_move`: The move played by Stockfish in UCI format - `fen`: Updated board position after the move - `legal_moves`: Updated list of legal moves ## Development To set up for development: ```bash git clone https://github.com/yourusername/chess-mcp.git cd chess-mcp pip install -e . ``` ## License MIT License