> ## 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.

# ToolChoiceSupport

Per-variant `tool_choice` support. `tool_choice` in `supported_parameters` only says the parameter is accepted; these flags say which of its values passed testing.

## Fields

| Field      | Type   | Required             | Description                                                                                  |
| ---------- | ------ | -------------------- | -------------------------------------------------------------------------------------------- |
| `auto`     | *bool* | :heavy\_check\_mark: | Whether the endpoint supports `"tool_choice": "auto"`.                                       |
| `function` | *bool* | :heavy\_check\_mark: | Whether the endpoint supports naming a function, `"tool_choice": {"type": "function", ...}`. |
| `none`     | *bool* | :heavy\_check\_mark: | Whether the endpoint supports `"tool_choice": "none"`.                                       |
| `required` | *bool* | :heavy\_check\_mark: | Whether the endpoint supports `"tool_choice": "required"`.                                   |