Codex CLI
Using OpenAI's Codex CLI as your AI agent
Codex CLI lets you use your OpenAI account with Agent Integration Kit.
You do not need to manually install @zed-industries/codex-acp. The ACP adapter binary ships with the plugin.
Setup
-
Install Codex CLI:
npm install -g @openai/codex -
Authenticate with one of these methods:
- ChatGPT subscription - Sign in when prompted (requires paid subscription)
- API Key - Set
CODEX_API_KEYorOPENAI_API_KEYenvironment variable
Run once in terminal to authenticate:
codex -
Open the Agent Chat window in Unreal and select Codex CLI
Plugin Settings
| Setting | Description |
|---|---|
| Codex CLI | Optional path override to codex executable (leave blank for auto-detect) |
| Bun/Node Runtime Override | Advanced override for adapter runtime; leave blank to use bundled runtime |
Features
- Context @-mentions
- Tool calls with permission requests
- TODO lists
- Slash commands (
/review,/init,/compact) - Custom prompts
Troubleshooting
| Issue | Solution |
|---|---|
Query closed before response received | Run codex in terminal and sign in again, then retry in Unreal |
| Codex not found | Run codex --version; if missing, install Codex CLI and set Codex CLI path override |
| Authentication issues | Run codex in terminal to re-authenticate |