Codex CLI is a high-performance, Rust-based coding agent from OpenAI that runs in your terminal. It's an AI-powered coding assistant that can understand and modify code directly from the command line. Powered by the GPT-5.4 ecosystem, Codex CLI provides developers with a ultra-low latency, workflow-integrated way to interact with code.
Codex CLI is built in Rust for the fastest possible terminal interaction:
- Ultra-low latency responses powered by GPT-5.4 mini
- Use AI assistance without leaving your terminal
- Seamlessly integrates with existing shell scripts and pipes
Not just generating code snippets, Codex CLI can:
- Understand your project structure
- Directly modify code in files
- Execute multi-step programming tasks with high speed
- Minimal configuration, works out of the box
- Focused on core programming tasks
- Doesn't disrupt your workflow
- Analyze project structure and dependencies
- Understand function and class purposes
- Trace code call relationships
- Automatically fix bugs
- Refactor code
- Add new features
- Ask questions directly in terminal
- Support pipes and redirections
- Works with shell scripts
npm install -g @openai/codexSet your OpenAI API key:
export OPENAI_API_KEY="your-api-key"# Ask a question
codex "What does this function do?"
# Ask it to modify code
codex "Help me refactor this function to be more readable"
# Specify a file
codex "Fix the bug in src/utils.js"# Start interactive mode
codex
# Analyze current directory's code
codex "Analyze this project's structure"
# Generate tests
codex "Generate unit tests for src/api.js"- Provide Context - Tell it what you're doing, and it will give better suggestions
- Iterate Gradually - Start with the big picture, then dive into details
- Verify Results - Always check and test AI-generated code yourself
- Use Interactively - Ask follow-up questions and have it refine solutions
Codex is developed by OpenAI and requires an OpenAI API key to use. Please follow OpenAI's terms of service.