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    SKILL.md
    Agent Skills
    Addy Osmani

    Addy Osmani's agent-skills, Explained: What Is Inside and How to Run Them in Any Agent

    Agent-Skills is an open-source project by Addy Osmani (Google Chrome DevRel) that provides production-grade engineering skills for AI coding agents. It focuses on encapsulating quality gates, best practices, and structured workflows into reusable skill files. The project uses the SKILL.md format and is compatible with Claude Code, Codex CLI, and other SKILL.md agents.

    May 14, 20264 min read
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    Quick Answer: Clone the repo, copy the folder for the skill you want into your agent's skills directory (~/.claude/skills/ for Claude Code, ~/.cursor/skills/ for Cursor, ~/.codex/skills/ for Codex CLI), and restart the agent. That's it.

    What Addy Osmani's agent-skills is

    Addy Osmani's agent-skills GitHub repo is a curated open-source collection of SKILL.md files aimed at production software work: refactoring, review, testing, documentation, and performance. It is a GitHub repository, not a marketplace. You install skills by copying folders.

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    What you get on this page that the repo does not

    The repo lists the skills. This page tells you which ones are worth running first, how to install each one in Claude Code, Cursor, or Codex CLI without hand-editing paths, and where the same behavior already exists as a one-click install on the Agensi marketplace.

    How to install any of Addy's skills

    git clone https://github.com/addyosmani/agent-skills
cp -r agent-skills/<skill-name> ~/.claude/skills/

    Swap ~/.claude/skills/ for ~/.cursor/skills/ or ~/.codex/skills/ depending on your agent.

    What's actually inside

    The repo groups skills by intent: code review, refactoring, testing, docs, performance auditing. Each folder is a single SKILL.md plus optional reference files, exactly as described in our SKILL.md format reference. Because it is standard SKILL.md, every skill in the repo runs in Claude Code, Cursor, Codex CLI, OpenCode, and OpenClaw.

    The equivalents already on Agensi

    If you want one-click install with versioning, security scans, and update notifications instead of manual copy-paste:

    See also our companion Addy Osmani agent-skills install guide.

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