Codex CLI Skill

OpenAI Codex CLI (@openai/codex) is a lightweight, open-source AI coding agent that runs locally in the terminal. It can read, edit, and execute code in your project directory using GPT-5 models.

Quick Reference

Installation

npm install -g @openai/codex
# Authenticate (browser or API key)
codex           # launches TUI with browser auth
export OPENAI_API_KEY="sk-..."  # or use API key