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OpenAI-compatible API

What is openai-compatible api?

An OpenAI-compatible API implements the same request and response shape as OpenAI’s chat completions endpoint. It lets existing client code point at a different model by changing a base URL and a key, with no other modification.

It has become the de facto interface for language model serving, which makes it a portability mechanism as much as a convenience: a stack built against it can move between providers without a rewrite.

Compatibility is a spectrum in practice. Core chat completion is near-universal; streaming, tool calling, structured output and log probabilities vary, and are worth checking against the specific features your client uses.

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