Install Project Brain in Codex

What you need first

• Codex, installed.
• Docker, which gives the docker command the server starts with.
• Your own values for YOUR_PROJECT_BRAIN_REPO_LIST,YOUR_PROJECT_BRAIN_STATE_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 project-brain --env PROJECT_BRAIN_REPO_LIST=YOUR_PROJECT_BRAIN_REPO_LIST --env PROJECT_BRAIN_STATE_DIR=YOUR_PROJECT_BRAIN_STATE_DIR -- docker run -i --rm -e PROJECT_BRAIN_REPO_LIST -e PROJECT_BRAIN_STATE_DIR ghcr.io/gentleelephant/project-brain:v2.0.3

2. Replace YOUR_PROJECT_BRAIN_REPO_LIST,YOUR_PROJECT_BRAIN_STATE_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 project-brain.

If it does not start

Cannot connect to the Docker daemon

Docker is not running. Start it, then restart Codex.

The server starts, but its tools fail

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