Install MySQL Legacy MCP in Codex

What you need first

  • Codex, installed.
  • Node.js, which gives the npx command the server starts with.
  • Your own values for YOUR_MYSQL_LEGACY_HOST,YOUR_MYSQL_LEGACY_USER,YOUR_MYSQL_LEGACY_PASSWORD.

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 mysql-legacy-mcp --env MYSQL_LEGACY_HOST=YOUR_MYSQL_LEGACY_HOST --env MYSQL_LEGACY_USER=YOUR_MYSQL_LEGACY_USER --env MYSQL_LEGACY_PASSWORD=YOUR_MYSQL_LEGACY_PASSWORD -- npx -y [email protected]
  1. Replace YOUR_MYSQL_LEGACY_HOST,YOUR_MYSQL_LEGACY_USER,YOUR_MYSQL_LEGACY_PASSWORD with your own values.
  2. Start Codex again and type /mcp: the server is listed.

Check it worked

Ask Codex: List the tools of mysql-legacy-mcp.

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.
The server starts, but its tools fail
A YOUR_… placeholder is still in the config, or its value is wrong.

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