Overview
What is Codex MCP Server?
An MCP server that connects Claude or Cursor to Codex CLI, enabling code analysis via @ file references, multi-turn conversations, sandboxed edits, and structured change mode. It is for developers who want to leverage Codex CLI’s capabilities through an MCP-compatible client.
How to use Codex MCP Server?
Install and add via claude mcp add codex-cli -- npx -y @trishchuk/codex-mcp-tool or configure in claude_desktop_config.json. Prerequisites: Node.js 18+ and a working Codex CLI installation (authenticated). Invoke tools like ask-codex, brainstorm, list-sessions, or health.
Key features of Codex MCP Server
- File analysis with
@file references - Multi-turn conversations with workspace isolation
- Native resume using
codex resume(CLI v0.36.0+) - Local OSS model support via Ollama or LM Studio
- Sandboxed code execution with
--full-auto - Structured brainstorming with SCAMPER framework
Use cases of Codex MCP Server
- Analyze code architecture by referencing files via
@src/ - Conduct multi-turn code review sessions using session IDs
- Run untrusted code safely in sandbox mode
- Generate refactoring ideas with structured brainstorming
- Use local models for code analysis without sending data to OpenAI
FAQ from Codex MCP Server
What are the runtime dependencies?
Node.js 18+ and a locally installed and authenticated Codex CLI are required.
How do I configure multi-turn conversations?
Pass a sessionId parameter in your prompt. Sessions persist for 24 hours by default (configurable via CODEX_SESSION_TTL_MS), with a maximum of 50 sessions.
What models are supported?
By default the CLI’s configured model is used. You can override with model names like gpt-5.5, gpt-5.4, gpt-5.4-mini, or use local OSS models via localProvider: "ollama" or "lmstudio".
Where does session data live?
Session data is stored locally on your machine under the Codex CLI workspace; no data is sent to external servers except through your chosen model provider.
What CLI versions are compatible?
Features work best with Codex CLI v0.36.0+ (sessions), v0.52.0+ (search), and v0.59.0+ (add-dirs, token limits).
