Adopt
The origin of the SKILL.md open standard and the canonical skills repo everyone else follows.
Why It Matters
github.com/anthropics/skills is where the SKILL.md format was born: folders with YAML frontmatter and markdown instructions. No compilation, no binaries, just markdown that agents follow. The format has been adopted by 16+ tools including Claude Code, Codex, Cursor, Gemini CLI, and GitHub Copilot. This isn't one standard among many — this IS the standard.
Strengths
- Elegant, zero-build format: a folder with a SKILL.md file is a complete skill
- Broadest tool adoption of any skill format (16+ agents and counting)
- First-party Anthropic maintenance means the spec evolves with Claude Code
- Cross-vendor by design — OpenAI, Google, and Microsoft tools all consume the same format
Limitations
- The standard is still young; versioning and dependency management are informal
- No built-in governance or security scanning — you trust the repo, not the format
- Community contributions go through Anthropic's review process, which can be slow
Risks
- SKILL.md is just markdown — there's zero sandboxing, no permission model, no capability restrictions; a malicious skill can instruct an agent to do anything
- "Cross-vendor standard" is generous; in practice, skills often need per-agent tweaking because each agent interprets instructions differently
- No dependency resolution: if skill A needs tool X installed and skill B conflicts with it, you're on your own
- The format's simplicity is both its strength and weakness — no schema validation means skills can be subtly broken and you won't know until runtime