Codex plugin for Claude Code
Use Codex from inside Claude Code for code reviews or to delegate tasks to Codex.
This plugin is for Claude Code users who want an easy way to start using Codex from the workflow they already have.
What You Get
/codex:reviewfor a normal read-only Codex review/codex:adversarial-reviewfor a steerable challenge review/codex:rescue,/codex:transfer,/codex:status,/codex:result, and/codex:cancelto delegate work, hand off sessions, and manage background jobs
Requirements
- ChatGPT subscription (incl. Free) or OpenAI API key.
- Usage will contribute to your Codex usage limits. Learn more.
- Node.js 18.18 or later
Install
Add the marketplace in Claude Code:
/plugin marketplace add openai/codex-plugin-ccInstall the plugin:
/plugin install codex@openai-codexReload plugins:
/reload-pluginsThen run:
/codex:setup/codex:setup will tell you whether Codex is ready. If Codex is missing and npm is available, it can offer to install Codex for you.
If you prefer to install Codex yourself, use:
npm install -g @openai/codexIf Codex is installed but not logged in yet, run:
!codex loginAfter install, you should see:
- the slash commands listed below
- the
codex:codex-rescuesubagent in/agents
One simple first run is:
/codex:review --background
/codex:status
/codex:resultUsage
/codex:review
Runs a normal Codex review on your current work. It gives you the same quality of code review as running /review inside Codex directly.
Note
Code review especially for multi-file changes might take a while. It's generally recommended to run it in the background.
Use it when you want:
- a review of your current uncommitted changes
- a review of your branch compared to a base branch like
main
Use --base <ref> for branch review. It also supports --wait and --background. It is not steerable and does not take custom focus text. Use /codex:adversarial-review when you want to challenge a specific decision or risk area.
Examples:
/codex:review
/codex:review --base main
/codex:review --backgroundThis command is read-only and will not perform any changes. When run in the background you can use /codex:status to check on the progress and /codex:cancel to cancel the ongoing task.
/codex:adversarial-review
Runs a steerable review that questions the chosen implementation and design.
It can be used to pressure-test assumptions, tradeoffs, failure modes, and whether a different approach would have been safer or simpler.
It uses the same review target selection as /codex:review, including --base <ref> for branch review.
It also supports --wait and --background. Unlike /codex:review, it can take extra focus text after the flags.
Use it when you want:
- a review before shipping that challenges the direction, not just the code details
- review focused on design choices, tradeoffs, hidden assumptions, and alternative approaches
- pressure-testing around specific risk areas like auth, data loss, rollback, race conditions, or reliability
Examples:
/codex:adversarial-review
/codex:adversarial-review --base main challenge whether this was the right caching and retry design
/codex:adversarial-review --background look for race conditions and question the chosen approachThis command is read-only. It does not fix code.
/codex:rescue
Hands a task to Codex through the codex:codex-rescue subagent.
Use it when you want Codex to:
- investigate a bug
- try a fix
- continue a previous Codex task
- take a faster or cheaper pass with a smaller model
Note
Depending on the task and the model you choose these tasks might take a long time and it's generally recommended to force the task to be in the background or move the agent to the background.
It supports --background, --wait, --resume, and --fresh. If you omit --resume and --fresh, the plugin can offer to continue the latest rescue thread for this repo.
Examples:
/codex:rescue investigate why the tests started failing
/codex:rescue fix the failing test with the smallest safe patch
/codex:rescue --resume apply the top fix from the last run
/codex:rescue --model gpt-5.4-mini --effort medium investigate the flaky integration test
/codex:rescue --model spark fix the issue quickly
/codex:rescue --background investigate the regressionYou can also just ask for a task to be delegated to Codex:
Ask Codex to redesign the database connection to be more resilient.
Notes:
- if you do not pass
--modelor--effort, Codex chooses its own defaults. - if you say
spark, the plugin maps that togpt-5.3-codex-spark - follow-up rescue requests can continue the latest Codex task in the repo
/codex:transfer
Creates a persistent Codex thread from the current Claude Code session and prints a codex resume <session-id> command.
Use it when you started a debugging or implementation conversation in Claude Code and want to continue that same context directly in Codex.
Examples:
/codex:transfer
/codex:transfer --source ~/.claude/projects/-Users-me-repo/<session-id>.jsonlThe plugin's existing SessionStart hook supplies the current transcript path automatically; --source is available as a manual override. The transfer uses Codex's external-agent session importer, so it follows the same conversion rules as importing Claude history in the Codex App and creates visible turns that can be continued in the App or TUI. The source must be under ~/.claude/projects, and older Codex versions that do not expose session import must be upgraded before using this command.
/codex:status
Shows running and recent Codex jobs for the current repository.
Examples:
/codex:status
/codex:status task-abc123Use it to:
- check progress on background work
- see the latest completed job
- confirm whether a task is still running
/codex:result
Shows the final stored Codex output for a finished job.
When available, it also includes the Codex session ID so you can reopen that run directly in Codex with codex resume <session-id>.
Examples:
/codex:result
/codex:result task-abc123/codex:cancel
Cancels an active background Codex job.
Examples:
/codex:cancel
/codex:cancel task-abc123/codex:setup
Checks whether Codex is installed and authenticated. If Codex is missing and npm is available, it can offer to install Codex for you.
You can also use /codex:setup to manage the optional review gate.
Enabling review gate
/codex:setup --enable-review-gate
/codex:setup --disable-review-gateWhen the review gate is enabled, the plugin uses a Stop hook to run a targeted Codex review based on Claude's response. If that review finds issues, the stop is blocked so Claude can address them first.
Warning
The review gate can create a long-running Claude/Codex loop and may drain usage limits quickly. Only enable it when you plan to actively monitor the session.
Typical Flows
Review Before Shipping
/codex:reviewHand A Problem To Codex
/codex:rescue investigate why the build is failing in CIStart Something Long-Running
/codex:adversarial-review --background
/codex:rescue --background investigate the flaky testThen check in with:
/codex:status
/codex:resultCodex Integration
The Codex plugin wraps the Codex app server. It uses the global codex binary installed in your environment and applies the same configuration.
Common Configurations
If you want to change the default reasoning effort or the default model that gets used by the plugin, you can define that inside your user-level or project-level config.toml. For example to always use gpt-5.4-mini on high for a specific project you can add the following to a .codex/config.toml file at the root of the directory you started Claude in:
model = "gpt-5.4-mini"
model_reasoning_effort = "high"Your configuration will be picked up based on:
- user-level config in
~/.codex/config.toml - project-level overrides in
.codex/config.toml - project-level overrides only load when the project is trusted
Check out the Codex docs for more configuration options.
Moving The Work Over To Codex
Delegated tasks and any stop gate run can also be directly resumed inside Codex by running codex resume either with the specific session ID you received from running /codex:result or /codex:status or by selecting it from the list.
This way you can review the Codex work or continue the work there.
FAQ
Do I need a separate Codex account for this plugin?
If you are already signed into Codex on this machine, that account should work immediately here too. This plugin uses your local Codex CLI authentication.
If you only use Claude Code today and have not used Codex yet, you will also need to sign in to Codex with either a ChatGPT account or an API key. Codex is available with your ChatGPT subscription, and codex login supports both ChatGPT and API key sign-in. Run /codex:setup to check whether Codex is ready, and use !codex login if it is not.
Does the plugin use a separate Codex runtime?
No. This plugin delegates through your local Codex CLI and Codex app server on the same machine.
That means:
- it uses the same Codex install you would use directly
- it uses the same local authentication state
- it uses the same repository checkout and machine-local environment
Will it use the same Codex config I already have?
Yes. If you already use Codex, the plugin picks up the same configuration.
Can I keep using my current API key or base URL setup?
Yes. Because the plugin uses your local Codex CLI, your existing sign-in method and config still apply.
If you need to point the built-in OpenAI provider at a different endpoint, set openai_base_url in your Codex config.
