> ## Documentation Index > Fetch the complete documentation index at: https://openrouter.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # ResponseFormat The response format. "json" (default) returns \{ text, usage }; "verbose\_json" additionally returns task, language, duration, and segment-level timestamps (OpenAI-compatible providers only). ## Example Usage ```python theme={null} from openrouter.operations import ResponseFormat # Open enum: unrecognized values are captured as UnrecognizedStr value: ResponseFormat = "json" ``` ## Values This is an open enum. Unrecognized values will not fail type checks. * `"json"` * `"verbose_json"`