Codex Setup

Codex is OpenAI's AI coding assistant. You can use it with either an API key or by logging in with your OpenAI account.

Install and Configure

1. Install codex-acp:

npm install -g @zed-industries/codex-acp

2. Find the installation path:

macOS/Linux

which codex-acp
# Example output: /usr/local/bin/codex-acp

Windows

where.exe codex-acp
# Example output: C:\Users\Username\AppData\Roaming\npm\codex-acp.cmd

3. Open Settings → Agent Client and set the Codex path to the path found above.

Authentication

Choose one of the following methods:

Option A: API Key

1. Get your API key from OpenAI Platform
2. Enter the API key in Settings → Agent Client → Codex → API key

Option B: Account Login

If you have a ChatGPT subscription and prefer not to use an API key, you can log in with your OpenAI account.

Important

This requires installing Codex CLI separately. The CLI creates the login session that the plugin uses.

1. Install Codex CLI:

npm install -g @openai/codex

2. Login via CLI:

codex

Follow the prompts to authenticate with your OpenAI account.

3. In Settings → Agent Client, leave the API key field empty.

TIP

The ChatGPT app uses a different authentication system. Having ChatGPT running does not authenticate the plugin — you must log in via the CLI.

Verify Setup

1. Click the robot icon in the ribbon or use the command palette: "Open agent chat"
2. Switch to Codex from the agent dropdown in the chat header
3. Try sending a message to verify the connection

Having issues? See Troubleshooting.