comment-hygienelisted

# Comment Hygiene Split from `code-hygiene` -- this is comment truthfulness only; dead code, reinvention/duplication, naming, and faking done stay in `code-hygiene`, which this skill sits alongside as a sibling of `code-structure` (the units and their contracts) and `readable-code` (how a body reads). A comment earns its place only by telling the reader something the **code cannot**. Sharp test: *could a competent reader recover this fact from the code (and the repo)? Yes -> delete; No -> maybe keep.* One fact survives that test despite being recoverable -- the sole exception, so bake it into the test: a **legal/provenance header** is recoverable from `LICENSE` yet kept inline by mandate (see EXEMPT). The **external-anchor WHY** looks like a second exception but isn't one: naming a constant recovers its *value*, never the spec/constraint that dictated it, so that rationale stays genuinely unrecoverable and keeps on the mainline (see KEEP). This truthfulness standard applies wherever the annotation lives -- inline comment, block comment, or docstring/doc-comment prose. A doc-comment that restates the signature, lies about behavior, or narrates a change is the same anti-pattern as an inline one. Docstring *format/completeness* defers to the language plugin (`pythonica`); *prose quality* to `docs-patterns`. ## KEEP -- the code can't say it Phrase each against the **invariant** that motivates it, not the current mechanics -- **evergreen**, so a refactor leaves it true. - **