Plymentor

A free chess training app for Windows with an AI coach, by Studio Nox. Download it from plymentor.com or the latest release.

What it does

• An AI coach that sees your board. Claude Code, ChatGPT (Codex CLI) or Gemini (Antigravity CLI) runs on your computer with your own account, inside the app. Through Plymentor's built-in tools it reads your board, runs Stockfish, analyses your games, shows positions and plays openings out move by move on the board, takes you to the right screen, switches Stockfish on or off for you, quizzes you, makes you play a game, an opening or an endgame out against Stockfish with a goal to reach, writes reports and adds them to your Reports screen, makes exercises from your mistakes, edits your opening repertoire with you, talks to you (optional voice) and remembers you between sessions.
• Stockfish 19 on your computer. Multi-threaded live analysis with an evaluation bar and engine lines, a judgement of every move you play, game review with an evaluation graph, and training games at eleven strengths.
• Your games, analysed. 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.
• Book reader. Add a chess book (PDF or EPUB) and Plymentor reads it to you with your coach's voice: the sentence it reads and the moves are marked on the page, and the board plays each move as the reading gets to it, with Stockfish's evaluation, and shows the book's diagrams. Older books in descriptive notation or with moves written out in words are followed too, a puzzle book's solutions are played on its puzzles and an exercise's answer on its position, diagrams set in chess fonts, drawn in ebooks' pictures or printed in scans are recognised, and scanned books are read (their text and their diagrams are recognised on your computer; pages in two columns are read column by column). A diagram read wrong can be set right on the board: the book is followed from it, and the reader learns that book's pieces from it. Pause, read faster, go back and forth through the moves — the book's and your own — while the reading waits, jump to any page by its number, zoom the page to any size, or click the page to read from anywhere.
• Training from your mistakes. Exercises made from the positions you got wrong, with spaced repetition, so they come back until they stick.
• Openings. Search openings by name or ECO code, explore them with Stockfish's evaluation, your own games and your own game database (a Scid 5 database you add, read on your computer), and keep White and Black repertoires — each opening's lines in a group of its own, imported from PGN with their comments — that you drill with spaced repetition, all together or one group at a time.
• Your data stays with you. No account and no Plymentor server: your games, analyses, notes and settings stay on your computer. Updates are signed by Studio Nox and install only when you say so.

Requirements: Windows 10 or 11 (64-bit). For the coach, an account with one of the providers: a Claude Pro or Max subscription (Claude Code), ChatGPT Plus or Pro (Codex CLI), or a Google account (Antigravity CLI). Plymentor installs the coach program for you with its maker's official installer.

Licence

Free software under the GNU AGPL v3 or later. The Studio Nox name and logo are trademarks of Studio Nox, not covered by the licence.

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.