Content integrity
you can audit.

Each visual lesson publishes its FEN, instructional prompt, marked squares and explanation. Any stated continuation is replayed for legality; any final check or checkmate state is asserted independently.

The release ledger covers all seven pathway stages and all nine extensions. Content, terminology, chess claims and the need for a board visual are reviewed separately.

The diagram title is stored inside the audited position rather than applied by the webpage. The build fails if a concept is relabelled, a visual ID is reused or two pattern cards publish the same FEN.

The file fingerprint proves which PDF was reviewed. The route and coverage classification show where—and how—the source appears on the site.

FIDE governs legal chess rules; Lichess and Chess.com provide independent terminology and training-theme checks; Stockfish supplies a separate machine analysis of every published board position.

Every recognised term links to the Chess Glossary. Preferred terms, aliases and anchor names are checked for uniqueness so that two expressions cannot silently point to conflicting definitions.

Every exact line starts from the normal initial position or a defined FEN. Chess.js replays SAN and asserts terminal states. Stockfish 18 Lite parses every teaching position, then compares every published first solution move with an unrestricted search at depth 18. A release fails if a solution loses more than 100 centipawns.

Pattern prompts without a full starting position remain valuable, but they are not misrepresented as engine-verified games.