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# Stage Runtime file

> Copy a durable File into an active Runtime workspace.

Copy a durable File into an active Runtime workspace. Staging creates a copy;
it does not move or delete the durable File.

## Stage a File

```ts
const result = await bctrl.tools.call("runtime.files.stage", {
  fileId: file.id,
  path: "reports/input.csv",
}, { runtimeId: runtime.id });

console.log(result.path, result.size);
```

The Runtime must be active. `path` is relative to the workspace root; absolute
paths and `..` segments are not allowed.

## Request parameters

| Parameter | Type     | Required | Description                                                     |
| --------- | -------- | -------- | --------------------------------------------------------------- |
| `fileId`  | `FileId` | Yes      | Durable File to copy.                                           |
| `path`    | `string` | Yes      | Workspace-relative destination path, from 1 to 1024 characters. |

## Response

| Field    | Type     | Always present | Description                          |
| -------- | -------- | -------------- | ------------------------------------ |
| `fileId` | `FileId` | Yes            | Durable File that was staged.        |
| `path`   | `string` | Yes            | Workspace-relative destination path. |
| `size`   | `number` | Yes            | Number of bytes staged.              |

## Next

* [Collect Runtime file](/sdk/tools/runtime/runtime-files-collect) — save a workspace file
* [List Runtime files](/sdk/tools/runtime/runtime-files-list) — inspect the workspace
* [Files](/sdk/files) — manage durable Files