Codex + Claude Code

How to install the Codex plugin for Claude Code and get started on a remote Coder environment.

Where are you installing?

Install Codex

Codex is installed globally via npm.

Local terminal

$npm install -g @openai/codex

Authenticate

Sign in to link your OpenAI account with the Codex CLI. Use device-code authentication so no browser needs to open in your terminal.

Local terminal

$codex login --device-auth

Welcome to Codex [v0.118.0]

OpenAI's command-line coding agent

Follow these steps to sign in with ChatGPT using device code authorization:

1. Open this link in your browser and sign in to your account

https://auth.openai.com/codex/device

2. Enter this one-time code (expires in 15 minutes)

XSB5-AKY4F

Device codes are a common phishing target. Never share this code.

Enter your work email and click Continue.

Install the Claude Code plugin

Choose how you access Claude Code.

Add the Codex marketplace to Claude Code.

Claude Code

>/plugin marketplace add openai/codex-plugin-cc

Install the plugin from the marketplace.

Claude Code

>/plugin install codex@openai-codex

Reload plugins to activate it.

Claude Code

>/reload-plugins

Run the setup wizard.

Claude Code

>/codex:setup

What you can do with it

Code review

/codex:review

Reviews your uncommitted changes (or a branch diff) and returns feedback inline. Pass --base <ref> to compare against any branch or commit.

Pressure-test your approach

/codex:adversarial-review

Actively challenges your design decisions and surfaces assumptions you may have missed. Useful before a big merge.

Delegate a complex task

/codex:rescue

Hand a stubborn investigation or fix to Codex and let it work in the background. Use /codex:status to check progress and /codex:result to retrieve the output.

The plugin uses your local Codex installation and authentication — no separate credentials needed. Work started here can be resumed in the Codex CLI with codex resume <session-id>.

openai/codex-plugin-cc