What problem does it solve? Codebases accumulate noise comments that restate code, reference tickets, or narrate history, while genuinely needed explanations of hidden constraints go missing. This Skill applies a strict decision framework to decide when a comment is justified and deletes everything else. ## Core Features & Use Cases - Decision flow for comment justification: Routes every candidate comment through checks (obvious from names and types, better name possible, hidden constraint) before allowing it. - Six justified categories: Non-obvious invariants, choice rationale with rejected alternatives, subtle semantics with tiny examples, external business constraints, surprising behavior, and structured TODO/FIXME. - Delete-on-sight rules and review mode: Flags restatements, history notes, section banners, type restatements, and commented-out code; check <path> audits a file without editing, explain <symbol> proposes the minimal comment. - Use Case: While reviewing a NestJS pull request, run the check mode on a service file to list every comment violating a rule with a recommendation such as delete, shorten, or rewrite as WHY. ## Quick Start Ask the assistant to check the comments in a specific file and list which ones should be deleted or rewritten.