x-goog-api-key header. The model ID appears in the URL, and messages use contents[].parts[]. Endpoints begin with /v1beta/models/.
:streamGenerateContent for streaming and /v1beta/cachedContents for explicit caching. Request and response fields use Gemini REST camelCase names. For the full schema, open API Reference → Chat completions → Gemini protocol. See Status codes and responses for errors and retry advice.
