Choosing a Protocol
Chuizi.AI supports four API protocols. All of them share the same authentication, billing, and rate limiting -- the only difference is the request/response format. Pick the one that matches your SDK or tool.
Decision Table
| Your situation | Protocol | Base URL | Why |
|---|---|---|---|
| Using OpenAI SDK, LangChain, or most AI tools | OpenAI | https://api.chuizi.ai/v1 | Industry standard. Works with 200+ models across all providers. |
| Using Claude Code, Cursor, Cline, or OpenCode | Anthropic | https://api.chuizi.ai/anthropic | Native passthrough. No format conversion. Full Anthropic feature support. |
| Using Google AI SDK | Gemini | https://api.chuizi.ai/gemini | Native Gemini format. Direct passthrough to Google/Vertex. |
| Using Codex CLI or GPT-5 Codex models | OpenAI | https://api.chuizi.ai/v1 | Gateway auto-translates to Responses API for Codex models. Use Chat Completions format as normal. |
| Building a new project, no preference | OpenAI | https://api.chuizi.ai/v1 | Widest model support. Most documentation and community resources. |
Next Steps
- Anthropic Messages API — Native passthrough protocol for Claude Code and Cursor
- Gemini API — Native passthrough protocol for Google AI SDK users
- Responses API — How Codex models work through Chat Completions