How do I clean code comments?

How do I clean up code comments in a diff or across the repository?

1. Choose the scope. Clean only the comments a diff introduces or changes. Clean the whole repository only when the user asks for it.
2. Apply the comment rules from the skill's comment-rules.md reference:
   • Use comments sparingly.
   • Do not comment out code — remove it instead.
   • Do not add comments that describe the process of changing code.
   • Do not use past-tense verbs — added, removed, changed, updated, or "now handles". Example of a bad comment: this.timeout(10_000); // Increase timeout for API calls — the reader cannot know what the timeout was increased from, and does not care about the old behavior.
   • Do not emphasize code versions ("this code now handles …").
   • Do not use end-of-line comments, except Doxygen ///< trailing comments, which are the established convention for documenting public API.
   • Place comments above the code they describe, at the same indentation.
3. Remove comment clutter:
   • commented-out code;
   • comments that restate the code or the method name;
   • edit-history narration.
4. Preserve necessary comments:
   • TODO=/=FIXME and similar work markers;
   • linter, formatter, compiler, and generated-code directives;
   • non-obvious reasoning, constraints, and business rules;
   • pre-existing comments during a diff-only pass.
5. Focus only on comments. Never change executable code, behavior, or unrelated formatting. Regenerate generated files instead of editing them.
6. Report the outcome. Produce a before/after table of every comment you changed (see the skill's before-after.md). If the code already complies, say so.

Not applicable — this is a manual workflow, not a script.

Manual QA: run the pass on a sample diff, then check the before/after table against comment-rules.md. CI does not exercise this recipe.

• code-review-comments — the skill this recipe serves.
• code review checklist — the Doxygen-on-public-API convention.