About skill-mirror
A live mirror of SKILL.md files across the major AI-agent skill libraries on public GitHub. Pure HTML + JSON. Refreshed every six hours from api.github.com and raw.githubusercontent.com. No authentication, no analytics, no tracking pixels.
Watched libraries
The seed list is configured in fetchers/skills.js. Every library is a real, public GitHub repo. If a repo or path disappears, that library is shown as "unavailable" — we do not invent skills.
- anthropics/skills — official Anthropic skills
- addyosmani/agent-skills — curated drop-in engineering skills
- mattpocock/skills — TypeScript / TDD / debugging / guardrail skills
- ananddtyagi/cc-marketplace — community Claude Code marketplace
- ComposioHQ/awesome-claude-plugins
- jeremylongshore/claude-code-plugins-plus-skills
- quemsah/awesome-claude-plugins
Refresh schedule
- Every 15 minutes — lightweight repo metadata refresh (stars, pushed_at)
- Every 6 hours — full skill ingest (trees + raw SKILL.md)
- Daily at 03:30 UTC — vacuum + prune old ingest log rows
Methodology
A "skill" is any file matching */SKILL.md inside a watched library's base_path. The file's name is taken from YAML frontmatter (name: field), falling back to the first # heading and then the folder basename. The slug is a normalised lowercase form of the name. Two skills with the same slug across different libraries are considered the same skill for comparison purposes.
What this is not
- Not a marketplace — it doesn't let you install anything.
- Not a security scanner — see skill-shield for that.
- Not a flat index — see skill-pulse.
- Not a conflict detector for a single library — see skill-clash.
API
JSON endpoints are documented in the README. The most useful ones:
/skill-mirror/api/stats/skill-mirror/api/libraries/skill-mirror/api/universal?min=3/skill-mirror/api/skill/<slug>/skill-mirror/api/skill/<slug>/diff?a=owner/repo&b=owner/repo