OpenAI Codex CLI
OpenAI's free, open-source terminal coding agent — runs agentic file editing, shell commands, and multi-step tasks powered by o4-mini.
Works with:chatgpt
Platform:windowsmaclinux
Articles featuring this tool
comparison
Claude Code vs Codex CLI vs Gemini CLI: Which Is Free?
Claude Code, Codex CLI, and Gemini CLI are all free to install — but only one is free to run. Decision tree for beginners with no IDE budget.
May 10, 2026
review
OpenAI Codex CLI Review: Free Terminal Coding Agent
OpenAI Codex CLI reviewed for beginners: setup, free tier limits, real running costs, and how it compares to Claude Code and Gemini CLI in 2026.
May 10, 2026