Agent Skills Specification
The open standard behind SKILL.md skills, with the spec and list of supporting tools.
About Agent Skills Specification
agentskills.io hosts the Agent Skills specification: the SKILL.md format, frontmatter fields, progressive disclosure and how agents should load skills. Anthropic created the format, published it as an open standard in December 2025, and in October 2026 handed it to the Agentic AI Foundation under the Linux Foundation.
Check the site's adopter list to see which agents support skills.
FAQ
What is Agent Skills Specification?
The open standard behind SKILL.md skills, with the spec and list of supporting tools.
Which agents does Agent Skills Specification work with?
Claude Code, Claude apps, OpenAI Codex, Gemini CLI, Cursor, VS Code & Copilot, Windsurf, ChatGPT.
Is Agent Skills Specification free?
Yes, it is free to use.
Alternatives to Agent Skills Specification?
Model Context Protocol, skill-creator, Skills CLI (skills.sh), Anthropic Example Skills, Awesome Claude Skills.