> ## 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.

# MessagesOutputConfigFormat

A schema to specify Claude's output format in responses. See [structured outputs](https://platform.claude.com/docs/en/build-with-claude/structured-outputs).

## Fields

| Field    | Type                                                                                                            | Required             | Description |
| -------- | --------------------------------------------------------------------------------------------------------------- | -------------------- | ----------- |
| `Schema` | map\[string]`any`                                                                                               | :heavy\_check\_mark: | N/A         |
| `Type`   | [components.MessagesOutputConfigTypeJSONSchema](../../models/components/messagesoutputconfigtypejsonschema.mdx) | :heavy\_check\_mark: | N/A         |