Claude Co-Commands plugin
Three Claude Code commands that bring Codex in for a second opinion on a plan, a plan critique and brainstorming in read-only mode
- 148 ★ on the repository
- Last commit
- MIT
Minimal access
Why this level
- Request and plan text goes to Codex, a second model vendor
- A background subagent starts an external `codex exec` process, though in a read-only sandbox
Install
- Works in
In your terminal, with SkillFoxx CLI
npx skillfoxx add plugins/claude-co-commandsDetects the agents on your machine, shows the access level and pins the version.
Other ways to install
Access and checks
How we reviewMinimal accessThe tool runs nothing and makes no network calls.
- Request and plan text goes to Codex, a second model vendor
- A background subagent starts an external `codex exec` process, though in a read-only sandbox
This is third-party code. Review the repository files before installing.
What it does
Claude Co-Commands adds three commands for working with the Codex CLI to Claude Code. `/co-brainstorm` discusses ideas and offers alternatives and critique, `/co-plan` builds a parallel plan and `/co-validate` reviews a plan as a staff engineer would. No MCP server is needed. The skills run Codex through a small helper, `scripts/codex-session`, which calls `codex exec` in a read-only sandbox and keeps each conversation in a temporary folder so follow-ups continue the same Codex session. A background subagent starts Codex and answers its clarifying questions while Claude does its own independent work. Version 2.0 dropped `codex mcp-server` because Codex 0.154.0 removed that command. The README explains how to delete the old server entry from `~/.claude.json` and `.mcp.json`.
Who it is for. Claude Code users with the Codex CLI installed who want an independent second plan or a critique of a decision from another model.
Good fit when
- Before a big task you want a second plan from another model to compare
- A finished plan deserves a harsh outside critique
- An idea needs discussion and alternatives without leaving Claude Code
- You need to call Codex with no MCP server and no window switching
Not a fit when
- The Codex CLI is not installed or you are not signed in
- The task is small and a second plan only costs time and tokens
- You need Codex to edit files: the helper runs it read-only
Example request
/co-validate Review my plan for migrating the database to PostgreSQL 17 and name the three weakest pointsLimitations
Claude Code and a signed-in Codex CLI (`codex login`) are required. The README installs Codex with `npm install -g @openai/codex` or `brew install codex`. Tokens are spent at both vendors, and your request and plan text goes to Codex. After updating the plugin, restart Claude Code and delete the old MCP server entry. The last commit is dated September 29, 2026.
How to disable. Run `/plugin uninstall co-commands@snakeo-co-commands` or delete the copied `co-brainstorm`, `co-plan` and `co-validate` folders from `~/.claude/skills`.
FAQ
Does the plugin need an MCP server?
No, since version 2.0 the commands call `codex exec` through the `scripts/codex-session` helper.
What if it reports Connection closed?
Remove the old `validate-plans-and-brainstorm-ideas` entry with `claude mcp remove` at user and project scope, then restart Claude Code.
Which commands does the plugin add?
`/co-brainstorm`, `/co-plan` and `/co-validate`.
Can Codex change files in this mode?
No, the helper runs Codex in a read-only sandbox.
How do I install the plugin?
With `/plugin marketplace add SnakeO/claude-co-commands` and `/plugin install co-commands@snakeo-co-commands`. As a fallback, copy the skill folders into `~/.claude/skills`.
Discussion
No questions or reviews yet.
Related
PluginsCodex MCP Server: Codex inside Claude Code
Codex MCP Server
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A Claude Code skill that hands implementation-heavy work to Codex CLI while Claude keeps planning, review and acceptance.
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Comparison with similar tools
Cards that share the main search query, and how they differ.
| Tool | Official | Authentication | Repository stars | Main difference |
|---|---|---|---|---|
| Claude Co-Commands (this card) | no | 148 | ||
| Codex plugin for Claude Code | no | 35,088 | three narrow commands for planning and critique with no standing bridge | |
| Codex MCP Server: Codex inside Claude Code | no | API key | 649 | no MCP server: Codex is started through `codex exec` |
README in short
The README lists three commands with descriptions and use cases, requirements for Claude Code and the Codex CLI and three install routes: plugin marketplace, clone and manual copy. A separate section explains moving from 1.x to 2.0 and checking after the update.