easy-codex-mcp

An MCP server that lets any MCP-compatible AI assistant have read-only conversations with OpenAI Codex CLI.

No complex setup — just codex login and you're ready.

Why?

Sometimes your AI assistant needs a second opinion. easy-codex-mcp bridges the gap by letting Claude, Cursor, or any MCP client consult Codex for code analysis, review, and Q&A — all in a non-destructive, read-only sandbox.

• 🔒 Read-only by design — Codex runs in sandbox mode. It reads your code but never modifies files or runs commands.

• 💬 Conversational — Start a thread and continue it later with full context preserved.

• 🔧 Zero config — No API keys to manage in your MCP config. Just log in to Codex CLI once.

Related MCP server: codex-cli-mcp

Quick Start

1. Install Codex CLI

npm install -g @openai/codex
codex login

2. Add to your MCP client

Claude Code (recommended):

claude mcp add easy-codex uvx -- --from git+https://github.com/dazebug/easy-codex-mcp easy-codex

Claude Desktop — add to your claude_desktop_config.json:

{
  "mcpServers": {
    "easy-codex": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/dazebug/easy-codex-mcp", "easy-codex"]
    }
  }
}

Other MCP clients — use the same config format with uvx as the command.

3. Use it

Your AI assistant now has two new tools:

Example prompts to your AI assistant:

• "Ask Codex to review this file for potential bugs"

• "Get Codex's opinion on the architecture of this module"

• "Have Codex explain how the authentication flow works"

Tools

start_new_conversation

Start a new read-only conversation with Codex.

Parameters:

• prompt (required) — What to ask Codex.

• working_directory (optional) — Directory for Codex to work in.

Returns: { "thread_id": "...", "response": "..." }

continue_conversation

Resume a previous conversation with full context.

Parameters:

• thread_id (required) — Thread ID from a previous conversation.

• prompt (required) — Follow-up question.

• working_directory (optional) — Directory for Codex to work in.

Returns: { "thread_id": "...", "response": "..." }

How It Works

Your AI Assistant  ──MCP──▶  easy-codex-mcp  ──CLI──▶  Codex (read-only sandbox)
       │                          │                          │
       │   "Review this code"     │   codex e --json "..."   │
       │◀─────────────────────────│◀──────────────────────── │
       │   thread_id + response   │   JSONL output           │

1. Your assistant calls the MCP tool with a prompt

2. easy-codex-mcp spawns codex CLI in read-only sandbox mode

3. Codex analyzes your code and responds

4. The response + thread_id are returned to your assistant

5. Use thread_id to continue the conversation later

Requirements

• Python 3.12+

• OpenAI Codex CLI (npm install -g @openai/codex)

• Codex CLI logged in (codex login)

Development

git clone https://github.com/dazebug/easy-codex-mcp.git
cd easy-codex-mcp
uv sync

# Run tests
uv run pytest

# Dev mode
uv run mcp dev src/easy_codex/server.py

License

MIT