| Format | Used by | What changes in your code |
|---|---|---|
| OpenAI-compatible | OpenAI, DeepSeek, Qwen, Moonshot, most aggregator gateways | base_url and api_key. Nothing else. Works with LangChain, LlamaIndex and the Vercel AI SDK unchanged. |
| Anthropic (Claude) | Claude models via the native Messages API | anthropic.Anthropic(base_url=..., api_key=...), or call /v1/messages directly. Tool use and streaming events keep the native Anthropic shape. |
| Google Gemini | Gemini models, AI Studio style | Gemini SDK with a custom base_url, or a compatible gateway endpoint. Multimodal input keeps the Gemini structure. |
Tell us which SDK your project uses when you order. We match the endpoint format to it rather than handing you a key that needs an adapter written first.
Choosing between them
Stay on OpenAI-compatible
If your code already calls OpenAI, or you might switch providers later. Every major library supports it, so moving again costs nothing.
Use Anthropic for Claude
When you rely on features that only exist in the native Messages API, such as its tool-use blocks, prompt caching or extended thinking.
Use Gemini for multimodal
When large image, PDF or audio inputs matter. The native format handles inline files and file references more directly.