> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter-d02e98a0-mintlify-7021d5f4.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ChatFunctionToolFunction - Python SDK

> ChatFunctionToolFunction method reference

<Warning>
  The Python SDK and docs are currently in beta.
  Report issues on [GitHub](https://github.com/OpenRouterTeam/python-sdk/issues).
</Warning>

## Fields

| Field           | Type                                                                                                                         | Required             | Description                          | Example                                                                                                                                                                                                                                                          |
| --------------- | ---------------------------------------------------------------------------------------------------------------------------- | -------------------- | ------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `cache_control` | [Optional\[components.ChatContentCacheControl\]](../components/chatcontentcachecontrol.md)                                   | :heavy\_minus\_sign: | Cache control for the content part   | `{"type": "ephemeral"}`                                                                                                                                                                                                                                          |
| `function`      | [components.ChatFunctionToolFunctionFunction](/client-sdks/python/api-reference/components/chatfunctiontoolfunctionfunction) | :heavy\_check\_mark: | Function definition for tool calling | `{"description": "Get the current weather for a location","name": "get_weather","parameters": {"properties": {"location": {"description": "City name","type": "string"}`<br />},<br />"required": \[<br />"location"<br />],<br />"type": "object"<br />}<br />} |
| `type`          | [components.ChatFunctionToolType](/client-sdks/python/api-reference/components/chatfunctiontooltype)                         | :heavy\_check\_mark: | N/A                                  |                                                                                                                                                                                                                                                                  |