OpenAI Codex woh AI model hai jo GitHub Copilot ke peeche hai - natural language ko code mein translate karta hai. Naya Codex CLI aaya hai jo terminal mein autonomous coding agent ki tarah kaam karta hai. Developers ke liye must-know!
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What is OpenAI Codex?
OpenAI Codex is an AI system that translates natural language instructions into code. Originally released in 2021, it powered the first version of GitHub Copilot and became the foundation for AI-assisted programming worldwide.
In 2025, OpenAI relaunched Codex as a cloud-based software engineering agent within ChatGPT - capable of performing multi-step coding tasks, browsing documentation, writing tests, and fixing bugs autonomously. Alongside this, Codex CLI was released as an open-source terminal-based coding agent that runs locally with your codebase.
Pros
7 items- Codex CLI is open-source and free
- Works directly in your terminal with your codebase
- Powered by OpenAI's o3 model (latest)
- Autonomous multi-step coding tasks
- Reads your codebase context for better suggestions
- Can run tests and verify its own code
- ChatGPT Pro integration for cloud-based use
Disadvantages
4 items- Codex cloud agent requires ChatGPT Pro ($200/mo)
- CLI requires OpenAI API key (paid)
- May need supervision for complex refactors
- Newer than alternatives like Cursor
Codex CLI - How to Use
Codex CLI is an open-source terminal agent that brings AI coding directly to your command line:
# Install Codex CLI
npm install -g @openai/codex
# Set your API key
export OPENAI_API_KEY=your-key-here
# Run a coding task
codex "Fix the memory leak in server.js"
# Or start interactive mode
codexCodex CLI Modes:
- Suggest mode (default): Shows you what it wants to do, asks approval
- Auto-edit mode: Edits files automatically, asks before running commands
- Full-auto mode: Does everything autonomously (use carefully)
Codex in ChatGPT (Cloud Agent)
In ChatGPT Pro, Codex can:
- Run entire software projects in a sandboxed environment
- Handle hours-long tasks asynchronously
- Create pull requests on GitHub
- Run tests and fix failing ones automatically
- Work on multiple tasks simultaneously
OpenAI Codex vs GitHub Copilot
| Feature | Codex CLI | GitHub Copilot |
|---|---|---|
| Autonomous tasks | ✅ | ❌ |
| Terminal-based | ✅ | ❌ |
| IDE integration | ❌ | ✅ |
| Price | API cost | $10/month |
| Codebase awareness | Full project | Open files |