> ## 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. # TimeRange ## Fields | Field | Type | Required | Description | Example | | ------- | -------------------------------------------------------------------- | -------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | -------------------- | | `end` | [date](https://docs.python.org/3/library/datetime.html#date-objects) | :heavy\_check\_mark: | ISO 8601 UTC timestamp. Must include seconds (YYYY-MM-DDTHH:MM:SSZ; fractional seconds allowed); minute-precision timestamps are rejected. | 2027-12-31T23:59:59Z | | `start` | [date](https://docs.python.org/3/library/datetime.html#date-objects) | :heavy\_check\_mark: | ISO 8601 UTC timestamp. Must include seconds (YYYY-MM-DDTHH:MM:SSZ; fractional seconds allowed); minute-precision timestamps are rejected. | 2027-12-31T23:59:59Z |