Write a Skill (Claude Code skill)
Skill for creating skills. /write-a-skill walks you through producing a clean SKILL.md with progressive disclosure (short main instruction + separate REFERENCE.md/EXAMPLES.md beyond 100 lines), routing-optimised description (max 1024 chars, third person, 'what + Use when' format), and utility scripts only when the operation is deterministic. Insists on the hard rule: the description is the ONLY thing your agent sees when deciding which skill to load, so it must list explicit triggers.
Strengths
- Enforces description discipline (explicit triggers), fixes the #1 bug of custom skills
- Clear progressive disclosure pattern: SKILL.md under 100 lines + separate REFERENCE/EXAMPLES files
- Explicit "add scripts when operation is deterministic" criterion, anti-bloat
- Provided review checklist, verifies triggers, size, examples, consistent terminology
Limitations
- No automated scaffolding: creates a SKILL.md but not the full skill-name/scripts/ tree
- The "100 lines max" recommendations are sometimes too strict for dense technical skills
- Simple tool, not an alternative to Anthropic's official skill-creator for production skills
Best for
- Devs discovering Claude Code skills who want to avoid beginner traps (fuzzy description, monolithic file)
- Teams maintaining an internal skills repo who want a unified format
- Trainers who want to transmit skill best practices quickly