factchk

1Check claims against reality in both directions before they ship.
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3## Goal
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5The author's judgment of what is plausible, absurd, or novel is the least reliable line in an artifact. Human priors fail **both ways**: they exclude the real (desert frogs exist) and normalize the impossible (weightless crates). `factchk` checks reality-grounded claims against external sources, then fixes errors or flags judgment calls. It checks claims about *the world*, not the soundness of a validation or the survival of a whole plan.
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7## Workflow
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91. Scan for **reality-grounded assertions** that call something plausible, realistic, absurd, novel, or impossible because of a factual premise. Include claims you are *about to write*.
102. Verify each against **external sources** (web search, open references) in **both directions**: could the "absurd" be real? Could the "obvious" or "novel" be false or long-established? If you cannot reach a source, **flag it; never assert from intuition**.
113. **Fix or flag:** correct mechanically clear errors, such as wrong dates, misattributed sources, or falsified numbers, with a cited source. Surface contested or interpretive claims as judgment calls; do not silently rewrite them.
124. Report each claim, its verdict, the source, and which direction a failed claim failed.
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14## Rules
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