What is OpenAI Codex CLI?
OpenAI Codex CLI is an experimental, lightweight, and fully open-source coding agent built in Rust that runs locally on your computer. It pairs with developers in the terminal, allowing natural language collaboration to read, modify, and run code. Codex CLI uses GPT-5-Codex, a version of GPT-5 optimized for agentic coding with a focus on real-world software engineering work. It's equally proficient at quick interactive sessions and independently powering through long, complex tasks. Released in April 2025, it represents OpenAI's commitment to terminal-based AI development tools.
✨ Key Features
- Open-source terminal agent
- GPT-5-Codex powered
- Local execution
- Built in Rust for performance
- Natural language interface
- Code reading and modification
- Task execution
- Internet access during tasks
🎯 Use Cases
- Terminal-based development
- Complex multi-step coding tasks
- Interactive coding sessions
- Local code execution
- Research and experimentation
- Learning advanced AI coding