Title: Improve rollout session initialization error messages Issue: https://github.com/openai/codex/issues/7283 What: add targeted mapping for rollout/session initialization errors so users get actionable messages when Codex cannot access session files. Why: session creation previously returned a generic internal error, hiding permissions/FS issues and making support harder. How: - Added rollout::error::map_session_init_error to translate the more common io::Error kinds into user-facing hints (permission, missing dir, file blocking, corruption). Others are passed through directly with `CodexErr::Fatal`. - Reused the mapper in Codex session creation to preserve root causes instead of returning InternalAgentDied.
npm i -g @openai/codex
or brew install --cask codex
Codex CLI is a coding agent from OpenAI that runs locally on your computer.
If you want Codex in your code editor (VS Code, Cursor, Windsurf), install in your IDE
If you are looking for the cloud-based agent from OpenAI, Codex Web, go to chatgpt.com/codex
Quickstart
Installing and running Codex CLI
Install globally with your preferred package manager. If you use npm:
npm install -g @openai/codex
Alternatively, if you use Homebrew:
brew install --cask codex
Then simply run codex to get started:
codex
If you're running into upgrade issues with Homebrew, see the FAQ entry on brew upgrade codex.
You can also go to the latest GitHub Release and download the appropriate binary for your platform.
Each GitHub Release contains many executables, but in practice, you likely want one of these:
- macOS
- Apple Silicon/arm64:
codex-aarch64-apple-darwin.tar.gz - x86_64 (older Mac hardware):
codex-x86_64-apple-darwin.tar.gz
- Apple Silicon/arm64:
- Linux
- x86_64:
codex-x86_64-unknown-linux-musl.tar.gz - arm64:
codex-aarch64-unknown-linux-musl.tar.gz
- x86_64:
Each archive contains a single entry with the platform baked into the name (e.g., codex-x86_64-unknown-linux-musl), so you likely want to rename it to codex after extracting it.
Using Codex with your ChatGPT plan
Run codex and select Sign in with ChatGPT. We recommend signing into your ChatGPT account to use Codex as part of your Plus, Pro, Team, Edu, or Enterprise plan. Learn more about what's included in your ChatGPT plan.
You can also use Codex with an API key, but this requires additional setup. If you previously used an API key for usage-based billing, see the migration steps. If you're having trouble with login, please comment on this issue.
Model Context Protocol (MCP)
Codex can access MCP servers. To configure them, refer to the config docs.
Configuration
Codex CLI supports a rich set of configuration options, with preferences stored in ~/.codex/config.toml. For full configuration options, see Configuration.
Execpolicy
See the Execpolicy quickstart to set up rules that govern what commands Codex can execute.
Docs & FAQ
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License
This repository is licensed under the Apache-2.0 License.

