Install PostFader in Codex

What you need first

• Codex, installed.
• uv, which gives the uvx command the server starts with.
• Your own values for YOUR_FL_BRIDGE_ENABLE_MIDI,YOUR_FL_BRIDGE_MIDI_PORT,YOUR_FL_STUDIO_USER_DATA_DIR.

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 postfader-fl-studio-mcp --env FL_BRIDGE_ENABLE_MIDI=YOUR_FL_BRIDGE_ENABLE_MIDI --env FL_BRIDGE_MIDI_PORT=YOUR_FL_BRIDGE_MIDI_PORT --env FL_STUDIO_USER_DATA_DIR=YOUR_FL_STUDIO_USER_DATA_DIR -- uvx postfader-fl-studio-mcp==12.0.3

2. Replace YOUR_FL_BRIDGE_ENABLE_MIDI,YOUR_FL_BRIDGE_MIDI_PORT,YOUR_FL_STUDIO_USER_DATA_DIR with your own values.
3. Start Codex again and type /mcp: the server is listed.

Check it worked

Ask Codex: List the tools of postfader-fl-studio-mcp.

If it does not start

spawn uvx ENOENT

uv is not on the PATH that Codex sees. Install it, or write the full path of uvx in the config.

The server starts, but its tools fail

A YOUR_… placeholder is still in the config, or its value is wrong.