> ## Documentation Index
> Fetch the complete documentation index at: https://test-8862363a-tembo-docs-computer-preview-keep-alive.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Computer

> Watch and control the sandbox desktop while a session runs.

The **Computer** tab streams the Linux desktop running inside your session's [sandbox](/features/sandbox/overview) into the Tembo dashboard. Use it to watch what an agent is doing in a browser or editor, and to take over with your own mouse and keyboard when you want to drive the environment yourself.

The desktop runs in the same VM as the agent, so both see the same `/workspace`, the same installed [dependencies](/features/sandbox/custom-dependencies), and the same [environment variables](/features/sandbox/environment-variables).

## Prerequisites

* The session runs in a VM sandbox.
* The VM is running. If it has stopped, send a message in the session to start it again.

## Open the Computer tab

1. Open a session in the [dashboard](https://app.tembo.io).
2. In the session's right sidebar, select **Computer**.

The sidebar also holds **Changes**, **Artifacts**, **Files**, **Terminal**, and **VM logs**. In the expanded view these open as tabs, so you can keep the desktop next to a diff or a terminal.

## What's on the desktop

A dock at the bottom of the desktop launches the tools bundled into the sandbox image:

| Dock item | Application        | Opens              |
| --------- | ------------------ | ------------------ |
| Menu      | Ulauncher          | Application search |
| Browser   | Chromium           | `about:blank`      |
| Files     | PCManFM            | `/workspace`       |
| Code      | Visual Studio Code | `/workspace`       |
| Terminal  | Ghostty            | `/workspace`       |

Because agents drive this same desktop, browser automation and other GUI work show up live in the preview.

## Copy and paste

The stream carries the clipboard in both directions, so you can copy text out of the sandbox desktop and paste your own text into it using your normal keyboard shortcuts.

## Copy or refresh the preview URL

While the **Computer** tab is open, two buttons appear in the sidebar header:

* **Copy computer URL** copies the preview URL so you can open the desktop in its own browser tab.
* **Refresh computer URL** re-establishes the tunnel to the desktop. Use it if the stream looks stale or blank.

<Note>
  The preview URL changes whenever the tunnel restarts. A URL you copied earlier stops working after a refresh or after the VM restarts — copy it again.
</Note>

## Preview states

| State                       | What it means                                                            |
| --------------------------- | ------------------------------------------------------------------------ |
| **Computer is booting up**  | The VM is still starting. The message names the current boot phase.      |
| **Refreshing computer URL** | A refresh is in flight. The preview reloads when the new URL is ready.   |
| **Computer unavailable**    | The session has no running VM. The preview appears once a VM is running. |

After the VM reports as running, the desktop stream can take up to about a minute to become available. Tembo keeps polling for it in the background and reloads the preview automatically.

## Constraints

* The desktop is streamed at 60 FPS from inside the sandbox. Throughput depends on your network connection to the tunnel.
* Docker-based sandboxes do not run a desktop, so the **Computer** tab stays unavailable for them.
* The desktop is part of the sandbox, so the stream ends when the VM stops. Extend the session's [keep-alive window](/features/sandbox/keep-alive) if you want the desktop to stay up after the agent finishes.