Chess vs Claude

Use when you want to play chess against your AI agent: a quick game, practice, or teaching a child the basics. Do not use for analysing finished games or solving puzzles.

Claude chooses every move and plays the way a human opponent would, with a little table talk that fits the level. A small rules script keeps the game honest. It holds the position, rejects illegal moves with a plain-language reason, and catches the classic AI failure where pieces drift or teleport around move 15. The script never picks moves for Claude.

Three levels: Beginner is friendly and explains its moves. Intermediate is a real game for club-level hobby players. Strong means Claude checks its candidate moves before it commits.

An HTML board from your side, with the last move highlighted, check marked and a move list. Click a piece to see where it can go and copy the move. Where HTML can't be shown, you get a text board.

The full rules are covered: castling, en passant, promotion, check, checkmate, stalemate, threefold repetition and the fifty-move rule. You can take back moves, ask for hints, offer a draw, resign or change level mid-game, and export the game as PGN for Lichess or Chess.com. Move input is flexible: e4, Nf3, O-O, e2-e4, nf3 or 0-0 all work.

Honest note: Claude plays by reasoning, not with a chess engine. At strong level it plays a solid club game but can miss long tactics. That is part of the fun.

Requirements: code execution with Python 3 and pip install chess. The skill installs it if it's missing. License: GPL-3.0-or-later, because the bundled script uses python-chess (GPL-3.0).