Install mnema: decision records for AI coding agents in Codex

What you need first

• Codex, installed.
• Node.js, which gives the npx command the server starts with.

Steps

1. Run this in a terminal. It writes the server into ~/.codex/config.toml, which the Codex CLI, its IDE extension and the ChatGPT desktop app share.

codex mcp add mnema -- npx -y @mnema/[email protected] mcp

2. Start Codex again and type /mcp: the server is listed.

Check it worked

Ask Codex: List the tools of mnema.

If it does not start

spawn npx ENOENT

Node.js is not on the PATH that Codex sees. Install it, or write the full path of npx in the config.