addyosmani--agent-skills/docs/codex-setup.md

Using agent-skills with Codex

This repository is also a Codex plugin. The same root-level skills/ directory used by Claude Code is consumed by Codex, so no files are copied or duplicated.

Install

codex plugin marketplace add addyosmani/agent-skills
codex plugin add agent-skills@agent-skills

Requires Codex CLI v0.122 or later. On older releases the command was codex marketplace add. See the Codex CLI docs.

The first command registers this repository as the agent-skills marketplace. The second command installs and enables the agent-skills plugin from that marketplace. Start a new Codex session after installation so the skills are discovered.

Local clones work too:

codex plugin marketplace add /path/to/your/clone
codex plugin add agent-skills@agent-skills

Usage

After install, invoke a skill in Codex chat with @ (e.g. @spec-driven-development) or just describe the task and let Codex pick the right skill. All 24 skills under skills/ are available.

How it works

• .codex-plugin/plugin.json — Codex plugin manifest at the repo root. Points skills at ./skills/ and provides the metadata required by Codex.
• .agents/plugins/marketplace.json — marketplace entry declaring the repo root (./) as the plugin source.
• skills/<name>/SKILL.md — unchanged. Codex and Claude Code share the same name + description frontmatter format, so one file serves both platforms.

Slash commands in .claude/commands/, personas in agents/, and the lifecycle hook under hooks/ stay Claude Code-specific. On Codex, invoke the underlying skill directly instead of the slash command (e.g. @spec-driven-development instead of /spec).