What is the quickest way to verify a notated game was played legally?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
Replay it through a rules engine rather than checking move by move by eye. An engine applies the full rule set, piece movement, screens, blocked legs, the flying general rule, check, to every single move automatically, catching a transcription error or an illegal move far more reliably than a manual read-through, especially over a long game.
Why manual checking is unreliable at scale
A human reader can verify one or two suspicious-looking moves quickly, but checking every move of a full game by hand for legality, including something as easy to miscount as a cannon's screen, is slow and error-prone. An engine performs the identical check on every move without fatigue.
What this catches that a casual read misses
Transcription mistakes are common in older or hand-recorded game collections, a mis-transcribed elephant move crossing the river, for instance, is exactly the kind of error that would slip past a casual reading but that an engine flags immediately as illegal.
Related questions
Does this site verify its own content this way?
Yes, every position published here is checked through the rules engine before the page goes live; see editorial standards.
Is this necessary for a casual game between friends?
Not usually, it matters most for historical collections, published books, or anywhere accuracy needs to be relied on beyond a single game.
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