Constant NOT_A_PAGE 

const NOT_A_PAGE: [&str; 3];

Site paths that are not published from a docs/**.md page, so check 2 has no file to look for.

§12’s layout puts four subtrees under each version, and only api/python/ among them is an mkdocs page (docs/api/python.md). The other three are copied in: api/rust/ is cargo doc --workspace --all-features, demo/ is the atune_showcase and atune_gui wasm builds, bench/ is benchmark.html. Parsing one of those back to docs/api/rust/atune/trait.Storage.html.md and demanding the file is a question with no answer, so they are skipped here — and skipping them is a real gap, named rather than hidden: whether a page in the rustdoc tree exists is G14’s question (check-api-links), and /demo/ and /bench/ arrive with the deploy slice that provisions them. What none of the three has today is any check that prose naming one of them resolves. §12 goes further and says prose should never spell such a URL at all — it names a symbol and api_links.yml resolves it — so the eventual right answer here is probably to reject rather than skip.