Requests (API)
Compatibility
What is supported on each API surface:
Feature matrix
| Feature | OpenAI · /v1/chat/completions | Anthropic · /v1/messages |
|---|---|---|
| Streaming (SSE) | ✓ | ✓ |
| Tool calling | ✓ | ✓ |
| Vision (images) | ✓ | ✓ |
| Reasoning / thinking | ✓ | ✓ |
| Any-model selection | ✓ | ✓ |
| usage.cost in response | ✓ | — |
Available features depend on the chosen model — e.g. vision only works on multimodal models. Check a model's provider for its capabilities.