1
Install the binary
Use the standalone installer (curl), npm, or Homebrew. Runs on macOS, Linux, and Windows natively.
2
Authenticate
Sign in with your ChatGPT account (Free through Enterprise) or set an API key for pay-per-token usage.
3
Choose sandbox mode
Defaults to workspace-write with OS native enforcement. Read-only for maximum safety, danger-full-access for unrestricted use.
4
Start coding
Run codex in your project directory for interactive use, codex exec for non-interactive CI/CD, or codex cloud exec for cloud tasks.
| Feature | Codex Cloud (Web) | Codex CLI | Codex Desktop App | |
|---|---|---|---|---|
| Runs where | Runs where | OpenAI cloud | Your local machine | Your local machine |
| Open source | Open source | Yes (Apache 2.0) | ||
| Local file access | Local file access | No (cloud only) | ||
| Computer Use | Computer Use | Yes (macOS, Windows) | ||
| Automations | Automations | Yes (cron scheduling) | ||
| MCP support | MCP support | Yes (client) | Yes (client + server) | Yes (client + server) |
| Sandboxing | Sandboxing | Cloud isolation | OS native (Seatbelt, bubblewrap, Windows Sandbox) | OS native |
| Delivers results as | Delivers results as | GitHub pull request | Direct file changes | Direct file changes or PR via cloud delegation |
When to use which surface
Use Codex CLI when you want a terminal workflow, need open source transparency, or want to use non-OpenAI providers. Use the desktop app for the richest experience with Computer Use, Automations, and Appshots. Use Codex Cloud for background tasks that benefit from isolation. Use the IDE extension to stay in your editor while delegating to the cloud. Use mobile remote control to steer tasks from your phone when you are away from your desk.