> ## 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.

# ModelReasoning

Reasoning effort configuration. Omitted for non-reasoning models and dynamic router models.

## Example Usage

```typescript theme={null}
import { ModelReasoning } from "@openrouter/sdk/models";

let value: ModelReasoning = {
  mandatory: false,
};
```

## Fields

| Field | Type | Required | Description | Example |
| - | - | - | - | - |
| `defaultEffort` | [models.DefaultEffort](../models/defaulteffort.mdx) | :heavy\_minus\_sign: | N/A | medium |
| `defaultEnabled` | *boolean* | :heavy\_minus\_sign: | Default reasoning enabled state when the client does not set `reasoning.enabled`. | |
| `mandatory` | *boolean* | :heavy\_check\_mark: | When true, reasoning cannot be disabled and effort "none" is rejected. | |
| `supportedEfforts` | [models.ReasoningEffort](../models/reasoningeffort.mdx)\[] | :heavy\_minus\_sign: | Allowed reasoning effort values for this model, in descending effort order (highest first). Null means no allowlist — all gateway effort values are accepted. | |
| `supportsMaxTokens` | *boolean* | :heavy\_minus\_sign: | Present and `true` when the model accepts `reasoning.max_tokens` in requests (Anthropic-style) instead of or in addition to `reasoning.effort`. Omitted otherwise. | |