> ## 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.

# SessionCostMeta

## Example Usage

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

let value: SessionCostMeta = {
  asOf: "2026-05-12T02:00:00.000Z",
  version: "v1",
  windowDays: 30,
  windowEndDate: "2026-05-11",
};
```

## Fields

| Field           | Type                                                                  | Required             | Description                                                                                    | Example                  |
| --------------- | --------------------------------------------------------------------- | -------------------- | ---------------------------------------------------------------------------------------------- | ------------------------ |
| `asOf`          | *string*                                                              | :heavy\_check\_mark: | ISO-8601 timestamp when the response was generated.                                            | 2026-05-12T02:00:00.000Z |
| `version`       | [models.SessionCostMetaVersion](../models/sessioncostmetaversion.mdx) | :heavy\_check\_mark: | Dataset version.                                                                               |                          |
| `windowDays`    | *number*                                                              | :heavy\_check\_mark: | Number of days in the weekly session sample window, or null when no snapshot is published.     | 30                       |
| `windowEndDate` | *string*                                                              | :heavy\_check\_mark: | UTC date of the final day in the session sample window, or null when no snapshot is published. | 2026-05-11               |