Claude Code now subcontracts to OpenAI Codex

What it does This MCP server is essentially well-placed glue code: it wraps the OpenAI Codex CLI, acting as a protocol translator that lets Claude Code invoke Codex for code generation, review, and web search. It exposes six tools—codex, review, websearch, listSessions, ping, and help—that map directly to underlying CLI capabilities. In practice, it lets one AI agent rent the specialized skills of another without you context-switching between chat windows.

The interesting bit Session persistence is the stand-out feature: you can pass a sessionId to the codex tool to resume multi-turn conversations across separate MCP invocations, turning stateless protocol calls into a threaded dialogue. When running against Codex CLI v0.87+, the server also harvests threadId and structured metadata from Codex responses and surfaces them back to the client, giving Claude a window into Codex’s internal conversation state.

Key highlights

• Wraps Codex CLI functionality into six MCP tools, including review for diffs and websearch for queries.
• Maintains conversational context across calls via sessionId and exposes active sessions through listSessions.
• Forwards structured output metadata like threadId when available from Codex CLI v0.87+.
• Ships with one-click install configurations for VS Code, VS Code Insiders, and Cursor.
• Requires a separate Codex CLI installation and an OpenAI API key.

Verdict Worth a look if you want Claude Code to orchestrate Codex without leaving your editor. Skip it if you already work directly in the Codex CLI or prefer your agents not to talk to each other.