> ## 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.

# ModelArchitecture

Model architecture information

## Fields

| Field              | Type                                                                                                    | Required             | Description                      | Example    |
| ------------------ | ------------------------------------------------------------------------------------------------------- | -------------------- | -------------------------------- | ---------- |
| `InputModalities`  | \[][components.InputModality](../../models/components/inputmodality.mdx)                                | :heavy\_check\_mark: | Supported input modalities       |            |
| `InstructType`     | optionalnullable.OptionalNullable\[[components.InstructType](../../models/components/instructtype.mdx)] | :heavy\_minus\_sign: | Instruction format type          | chatml     |
| `Modality`         | `*string`                                                                                               | :heavy\_check\_mark: | Primary modality of the model    | text->text |
| `OutputModalities` | \[][components.OutputModality](../../models/components/outputmodality.mdx)                              | :heavy\_check\_mark: | Supported output modalities      |            |
| `Tokenizer`        | [\*components.ModelGroup](../../models/components/modelgroup.mdx)                                       | :heavy\_minus\_sign: | Tokenizer type used by the model | GPT        |