> ## 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.

# OpenAIResponsesToolChoiceUnion - TypeScript SDK

> OpenAIResponsesToolChoiceUnion method reference

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

## Supported Types

### `models.OpenAIResponsesToolChoiceAuto`

```typescript lines theme={null}
const value: models.OpenAIResponsesToolChoiceAuto = "auto";
```

### `models.OpenAIResponsesToolChoiceNone`

```typescript lines theme={null}
const value: models.OpenAIResponsesToolChoiceNone = "none";
```

### `models.OpenAIResponsesToolChoiceRequired`

```typescript lines theme={null}
const value: models.OpenAIResponsesToolChoiceRequired = "required";
```

### `models.OpenAIResponsesToolChoiceFunction`

```typescript lines theme={null}
const value: models.OpenAIResponsesToolChoiceFunction = {
  type: "function",
  name: "<value>",
};
```

### `models.OpenAIResponsesToolChoice`

```typescript lines theme={null}
const value: models.OpenAIResponsesToolChoice = {
  type: "web_search_preview",
};
```