Your chess coach, on your computer.
Plymentor is a free chess training app for Windows. An AI coach (Claude, ChatGPT or Gemini, with your own subscription) explains positions, reviews your games with Stockfish, writes reports from your own games and turns your mistakes into exercises.
Claude Code, ChatGPT (Codex CLI) or Gemini (Antigravity CLI), with your own subscription, built into the app. Your coach sees your board, runs Stockfish, reads your games, quizzes you, talks to you and remembers you between sessions.
Multi-threaded live analysis, a judgement of every move you play, game review with an evaluation graph, and training games at eleven strengths.
Import PGN files or download your games from Lichess and Chess.com, analyse them in batches, and get statistics and a written report with examples from your own games.
Exercises made from the positions you got wrong, with spaced repetition, so they come back until they stick.
Search openings by name, keep a repertoire and drill it, and explore your own games and your own game database (a Scid 5 database you add).
No account and no Plymentor server: your games, analyses and notes are kept on your computer. The coach works through the AI service you choose, with your own account. Updates install only when you say so, and they’re signed by Studio Nox.
Plymentor is free software under the GNU AGPL v3 or later: source code · releases · security. Claude is a trademark of Anthropic, ChatGPT of OpenAI and Gemini of Google; Plymentor isn’t affiliated with or endorsed by them. Chess pieces in the screenshot: cburnett by Colin M.L. Burnett (GPL-2.0-or-later).
Disclaimer: connecting an AI coach (Claude Code, ChatGPT or Gemini) to Plymentor and using it uses your own account with that provider — its tokens, credits or usage limits — and may cost you money. Studio Nox takes no responsibility for any costs, charges or other monetary matters arising from connecting or using a coach.
Studio Nox