Codex
OpenAI's coding-focused product line — currently a CLI agent and IDE integration competing with Claude Code.
Definition
Codex is OpenAI's brand for code-specialised tooling, currently shipped as the Codex CLI (open-source) and Codex agent inside ChatGPT. Codex agents run shell commands, edit files, and report back, the same workflow as Claude Code and Cursor agent. The name originally referred to OpenAI's 2021 coding model that powered the first GitHub Copilot.
When to use
See also
- Claude Code — Anthropic's official terminal-based coding agent, with MCP support and a plugin ecosystem.
- Cursor — An AI-first code editor forked from VS Code that integrates LLM completions, chat, and agent loops natively.
- GitHub — Microsoft-owned Git hosting platform — the default home for open-source code, issues, pull requests, and CI.