Check Loop — AI skill for Claude Code

check-loop is a plugin for Claude Code and pi that asks Codex to review a plan before you build it, check a research draft, or review code as you work through an approved plan.

The model your session runs on is the orchestrator. It runs the workflow and checks the review findings. A fresh subagent implements each step on the same model unless you set an implementer model. Codex reviews the work with the model and reasoning effort you choose, or with your Codex defaults.

A review finding needs evidence before it can block progress. The orchestrator opens the cited source instead of accepting a concern because another model raised it.

Current version: 5.2.1. The first release shipped in March 2026, ten days before OpenAI's own Codex plugin for Claude Code and before the other cross-model review loops credited in the changelog.

Install

You need Claude Code 2.1.257 or later or pi, plus Node.js 18 or later and an authenticated Codex CLI.

Install Codex and sign in from your terminal:

npm install -g @openai/codex
codex login

On a headless machine, use `codex login --device-auth`.

Claude Code

Run these commands inside Claude Code:

/plugin marketplace add Novacon/check-loop
/plugin install check-loop@lordknows13-check-loop
/reload-plugins

The skills do not switch models. Start the session on the model and effort you want, for example with `claude --model fable`.

To update:

/plugin marketplace update lordknows13-check-loop
/plugin update check-loop@lordknows13-check-loop
/reload-plugins

Restart Claude Code if the update asks you to. Updates keep your settings, because they live outside the plugin cache.

pi

pi install git:github.com/Novacon/check-loop

To use a local clone, pass its path instead: `pi install ./check-loop`.