# Comments Explain Why

> Good comments explain: business rules ("Tax is calculated differently for EU customers due to VAT... Use when documenting code and APIs. Documentation category skill.

- Skill: `majiayu000/comments-explain-why` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add majiayu000/comments-explain-why`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/comments-explain-why/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Docs & Writing
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/majiayu000/comments-explain-why

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# Comments Explain Why

Good comments explain: business rules ("Tax is calculated differently for EU customers due to VAT regulations"), workarounds ("Using setTimeout because the library has a race condition - see issue #123"), non-obvious decisions ("We use insertion sort here because n is always small and it's faster for nearly-sorted data"). Don't comment what is obvious from the code itself.