1. What is Codex?
OpenAI Codex (Codex CLI) is OpenAI's official terminal coding agent that supports custom API endpoints. By pointing it to our gateway's OpenAI-compatible entry point, you can use GPT series models with your sk- key.
2. Installing Codex CLI
npm install -g @openai/codexAfter installation, enter codex in your terminal; switch models using codex --model gpt-5.4 or through the model selection menu during interaction.
3. Configuring Codex
① Environment Variables (Fastest)
export OPENAI_BASE_URL="https://www.relay-api.com/v1"
export OPENAI_API_KEY="sk-your-key"
codex --model gpt-5.4② config.toml (Recommended for long-term use)
# ~/.codex/config.toml
[model_providers.myrelay]
name = "Azztimes Relay"
base_url = "https://www.relay-api.com/v1"
env_key = "OPENAI_API_KEY"
wire_api = "chat"
[model]
model_provider = "myrelay"
model = "gpt-5.4"Save the file and run codex --model gpt-5.4 to get started.
4. API Endpoint Reference
| Model Group | Base URL | Protocol |
|---|---|---|
| Claude / Anthropic | https://www.relay-api.com | Anthropic Messages |
| GPT / OpenAI | https://www.relay-api.com/v1 | OpenAI Chat Completions |
| Gemini | https://www.relay-api.com/v1beta | Google generateContent |
5. Troubleshooting
| Issue | Solution |
|---|---|
| 401 / 403 | Invalid key, disabled, or insufficient balance; verify the sk- key and top up if necessary. |
| 404 / Model unavailable | The model name does not match the platform slug, or the model is not enabled; check the model ID. |
| Unknown model | Ensure the model ID is precise (including case sensitivity); verify it via the Model Plaza. |
Security Note: Do not commit your API key to public repositories. Use .env files or environment variables. Generation tasks can consume significant tokens, so keep an eye on your balance.