Verify a claim against the source

The failure this skill prevents: a page states a default, a precedence order, or a field name that reads plausibly, passes Vale and the link checker, and is wrong. Nothing in CI checks whether a sentence about product behavior is true. A reviewer who knows the product catches some of it; the rest reaches readers.

Published docs, a README, and a model's recollection are all secondary sources. Prefer evidence you produced in this session.

Step 1. Pick the strongest evidence available

Work down this list and stop at the first rung you can actually reach. Each rung is weaker than the one above it.