> ## 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.

# CustomTool - Python SDK

> CustomTool method reference

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

Custom tool configuration

## Fields

| Field         | Type                                                                                                 | Required             | Description |
| ------------- | ---------------------------------------------------------------------------------------------------- | -------------------- | ----------- |
| `description` | *Optional\[str]*                                                                                     | :heavy\_minus\_sign: | N/A         |
| `format_`     | [Optional\[components.Format\]](/client-sdks/python/api-reference/components/format-)                | :heavy\_minus\_sign: | N/A         |
| `name`        | *str*                                                                                                | :heavy\_check\_mark: | N/A         |
| `type`        | [components.CustomToolTypeCustom](/client-sdks/python/api-reference/components/customtooltypecustom) | :heavy\_check\_mark: | N/A         |