OpenAI ships Codex into Claude Code — two commands, or four?

OpenAI shipped an official plugin, codex-plugin-cc, that runs its Codex coding agent from inside Anthropic's Claude Code CLI. The plugin delegates to the existing Codex CLI and app server, reusing auth and configuration, and is Apache-2.0 licensed. OpenAI stated: 'It is not a separate runtime. It is Codex, just invoked from inside Claude Code.'

A rare thing happened on March 30, 2026: OpenAI shipped first-party tooling straight into a competitor's terminal. The result is codex-plugin-cc , and it changes how a two-agent workflow fits in one window. codex-plugin-cc is an official OpenAI plugin that runs the Codex coding agent from inside Anthropic's Claude Code CLI. It lives at openai/codex-plugin-cc https://github.com/openai/codex-plugin-cc , is Apache-2.0 licensed, and is effectively pure JavaScript . The notable part is the direction of travel — a frontier-model vendor packaging tooling for a rival's ecosystem. It is not a new runtime. As OpenAI puts it in its developer-forum announcement: "It is not a separate runtime. It is Codex, just invoked from inside Claude Code." — OpenAI source: OpenAI Developer Community The plugin delegates to the Codex CLI and app server already installed on your machine, reusing your existing auth and configuration . Maintenance is active: v1.0.0 landed March 30, 2026, and the current v1.0.6 shipped July 8, 2026 — six patch releases in four months . This is the same Codex agent that hit more than 5 million weekly users by June 2026 , surfaced in a different terminal. The prerequisites are modest but specific. You need Node.js 18.18.0 or later — this is a hard engine constraint declared in the plugin's package.json engines: " =18.18.0" , not an advisory floor, so an older runtime will refuse to install . On the account side, either a ChatGPT subscription — the free tier qualifies — or an OpenAI API key unlocks Codex . Auth is inherited, not re-entered. If you are already logged into Codex locally, the plugin reuses that state automatically — no second login . No Codex installed yet? /codex:setup can offer to run npm install -g @openai/codex when npm is present, or you can run that command manually first . The full official path is four slash commands run inside an active Claude Code session, not the two the viral clip advertises . Work through them in order: /plugin marketplace add openai/codex-plugin-cc /plugin install codex@openai-codex codex , the marketplace is openai-codex , which is why the reference reads codex@openai-codex . /reload-plugins /codex: skills never surface, and the codex:codex-rescue subagent stays absent from /agents . /codex:setup npm install -g @openai/codex ; if Codex is present but not logged in, it prompts you to run codex login from Claude Code .Verify before you rely on it: once /codex:setup completes without complaint, /codex:review should respond, and the codex:codex-rescue subagent should be visible in /agents . If either is missing, re-run /reload-plugins — a skipped reload is the most common reason the command surface fails to appear. The viral "two commands, 30 seconds" pitch covers only the marketplace add and the plugin install — steps 1 and 2. Skip /reload-plugins and the plugin is registered but dormant: its /codex: slash commands never load into the running session, so nothing appears to work . Skip /codex:setup and the plugin never checks whether Codex is installed and authenticated — the failure is silent rather than a readable error, which is the worst kind to debug . Two behaviors deserve caution before you lean on this in real work: Stop hook to fire Codex on every Claude response. OpenAI and practitioners warn this can spin up a sustained Claude/Codex loop that drains usage limits fast — treat it as optional, not a default .Keep it current, too. v1.0.6 , released July 8, 2026, removed shell expansion for git commands — a correctness and security fix for a plugin that shells out inside your repo. Earlier builds carried Windows-compatibility and app-server readiness regressions, so pin a recent version . After /codex:setup completes, the plugin exposes a focused set of /codex: slash commands plus a codex:codex-rescue subagent visible in /agents . This is a command surface, not a general orchestration runtime — each command maps to one Codex action against your local checkout. | Command | What it does | Key flags | |---|---|---| /codex:review | Read-only Codex review of uncommitted changes or a branch diff | --base , --wait , --background | /codex:adversarial-review | Same target selection, but a skeptical pass that questions design decisions and assumptions, not just bugs | --base + optional focus text | /codex:rescue | Delegates investigation or a fix to the codex:codex-rescue subagent | --model spark → gpt-5.3-codex-spark , --resume , --fresh , --effort | /codex:transfer | Hands the active Claude Code session into a persistent Codex thread for longer delegation added in v1.0.5 | — | /codex:status · /codex:result · /codex:cancel | Manage background jobs | — | One practical habit: before you lean on a blocking --wait , run background jobs and poll them with /codex:status and /codex:result , cancelling with /codex:cancel — --wait ties up your terminal until Codex returns . The concrete takeaway: install a pinned recent build, run /codex:review once to confirm the subagent responds, then wire the review commands into your ship checklist — you now have Claude planning and Codex reviewing in a single terminal . No. A ChatGPT free-tier account qualifies, and an OpenAI API key works as well . The plugin does not maintain its own credentials — it reuses whatever authentication your local Codex install already holds. If you are already logged into Codex on the machine, that auth is picked up automatically; if not, run codex login from Claude Code once and you are set. No. Codex usage counts against your Codex limits, and Claude usage against Claude's — there is no shared quota, no cross-account auth, and no linked billing . The plugin is a convenience bridge that invokes your locally installed Codex CLI and app server; it does not prove the two agents share context, accounts, or permissions. Watch the optional "review gate" in particular, since a Claude/Codex loop can drain Codex limits fast. You most likely stopped at the two install commands and skipped /reload-plugins . Adding the marketplace and installing the plugin registers it, but the running session has not yet loaded the new skills. Run /reload-plugins , then /codex:setup , and the /codex: slash commands plus the codex:codex-rescue subagent will show up in /agents . This is why the "two-command" framing is really four. /codex:review runs a standard, read-only Codex pass over uncommitted changes or a branch diff against a base ref such as main , supporting --base , --wait , and --background . /codex:adversarial-review runs a steerable, skeptical pass that actively questions design decisions and assumptions, using the same target selection plus optional focus text. Reach for the adversarial pass when you want a pre-merge second opinion, not a routine change summary. No. openai/openai-developers-for-claude is a separate plugin that bundles a Docs MCP server and API-setup skills, while openai/codex-plugin-cc exposes the Codex coding agent itself . They live in different repositories and serve different purposes; installing one does not give you the other. If your goal is code review and task delegation, codex-plugin-cc is the one you want.