OpenAI launches a Codex plugin that runs inside Anthropic's Claude Code

OpenAI released a plugin that embeds its AI coding assistant Codex directly into Anthropic's Claude Code.

The plugin offers three core features: a standard code review, a more aggressive "adversarial review" that specifically challenges weaknesses and design decisions, and the ability to hand off tasks to Codex in the background. It requires a ChatGPT subscription (including the free tier) or an OpenAI API key, plus Node.js version 18.18 or higher.

The plugin doesn't install a separate program. Instead, it uses the Codex installation already on the machine, with the same settings and credentials. Users can also enable a "Review Gate" that prevents Claude Code from finalizing changes until Codex has reviewed them.

Meeting developers where they already work

Strategically, the plugin is a pragmatic move. Claude Code dominates the market right now. Rather than waiting for developers to switch to Codex, OpenAI is bringing its Codex model directly into their existing workflow. Every review triggered through the plugin runs on OpenAI's infrastructure and generates usage.

At the same time, the plugin creates a direct touchpoint with the model. Developers get to experience Codex's capabilities in their day-to-day work without having to actively switch tools. That also applies to every update and every new model OpenAI ships in the coming weeks and months.

OpenAI shifts its strategic focus

The plugin fits into a broader strategic overhaul at OpenAI. According to a Wall Street Journal report, the company plans to refocus its resources on coding tools and enterprise customers. Fidji Simo, OpenAI's CEO of Applications, reportedly called the success of Anthropic's Claude Code and Cowork an internal "wake-up call."

OpenAI also plans to merge ChatGPT, Codex, and its Atlas browser into a single desktop app. Greg Brockman is reportedly leading the transition. According to Simo, the previous strategy of launching too many products at once - including Sora, Atlas, and a hardware device - slowed the company down.

The plugin is essentially a Trojan horse. The goal is to establish Codex as a useful addition to developers' workflows and gradually get them comfortable with OpenAI's ecosystem. It's available on GitHub at openai/codex-plugin-cc and has already collected more than 3,700 stars.