Ask Codex MCP server

Ask LLM

Give your AI coding assistant a second opinion — from a different model.

Claude Code, Codex CLI, Cursor, Claude Desktop, or any of 40+ MCP clients can call Codex, Claude, Grok, Antigravity, Ollama, or Gemini to review a diff, debate a plan, or catch the bug the first model missed. Standard MCP; no prompt hacks.

Quick Start · Choose a reviewer · Claude Code plugin · Docs · Packages

You:    ask codex to review src/auth.ts for security issues
Codex:  ⚠ verifyToken() compares tokens with === — not timing-safe (line 42)
        ⚠ the session cookie is missing a SameSite attribute
Claude: Good catches — applying both fixes to src/auth.ts.

One prompt. A second model reviews independently; your assistant applies the fix. No copy-pasting between tools.

Why a second opinion?

Your primary AI is confident, but confidence isn't correctness. A second model with no stake in the first answer catches what it glossed over.

Quick Start

Prerequisites: Node.js 20+ on Linux or macOS, and at least one provider CLI installed and authenticated (see Provider setup).

Claude Code

# One install, every provider — auto-detects what you have
claude mcp add --scope user ask-llm -- npx -y @ask-llm/mcp
# first-class alternative after `npm install -g @ask-llm/mcp`:
# claude mcp add --scope user ask-llm -- ask-llm-mcp

Then try: ask codex to review my last commit. Run npx @ask-llm/mcp doctor if anything looks off.

Advanced: install split provider packages instead

claude mcp add --scope user codex -- npx -y @ask-llm/codex-mcp
claude mcp add --scope user grok -e XAI_API_KEY="$XAI_API_KEY" -- npx -y @ask-llm/grok-mcp
claude mcp add --scope user antigravity -- npx -y @ask-llm/antigravity-mcp
claude mcp add --scope user ollama -- npx -y @ask-llm/ollama-mcp
claude mcp add --scope user gemini -- npx -y @ask-llm/gemini-mcp

Cursor

Add to .cursor/mcp.json (project) or ~/.cursor/mcp.json (user):

{
  "mcpServers": {
    "ask-llm": { "command": "npx", "args": ["-y", "@ask-llm/mcp"] }
  }
}

Codex CLI

# ~/.codex/config.toml
[mcp_servers.ask-llm]
command = "npx"
args = ["-y", "@ask-llm/mcp"]

Shortened. The full README is on GitHub.