Codex

OpenAI's open-source coding CLI. Runs locally with sandboxed file and shell access, with bindings for VS Code, Cursor, and Windsurf.

How skills install

Codex reads skills from .codex/skills/ in a project. Same spec, same layout: folder plus SKILL.md.

Skills in the catalog

317 indexed skills run on this runtime, including spec-compliant runtime-agnostic skills.