> ## 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.

# ContainerFile

## Example Usage

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

let value: ContainerFile = {
  bytes: 123,
  containerId: "sess_abc123",
  createdAt: 1755640000,
  id: "cfile_b3V0L3JlcG9ydC5jc3Y",
  object: "container.file",
  path: "out/report.csv",
  source: "assistant",
};
```

## Fields

| Field | Type | Required | Description | Example |
| - | - | - | - | - |
| `bytes` | *number* | ✔️ | File size in bytes. | 123 |
| `containerId` | *string* | ✔️ | The container the file belongs to — echoes the `container_id` path parameter (OpenAI field name). | sess\_abc123 |
| `createdAt` | *number* | ✔️ | Unix timestamp (seconds) when the file was last synced. | 1755640000 |
| `id` | *string* | ✔️ | Container file id: `cfile_` + base64url of the file path. | cfile\_b3V0L3JlcG9ydC5jc3Y |
| `object` | [models.ContainerFileObject](../models/containerfileobject.mdx) | ✔️ | N/A | container.file |
| `path` | *string* | ✔️ | Container-relative file path. | out/report.csv |
| `source` | [models.ContainerFileSource](../models/containerfilesource.mdx) | ✔️ | Container files are always produced by the assistant sandbox. | assistant |