> For the complete documentation index, see [llms.txt](https://docs.testvibe.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.testvibe.com/runners/choose-a-runner.md).

# Choose an Execution Target

Every project runs on one of three execution targets. The choice comes down to two things: whether your application is reachable from the public internet, and where you want the AI-generated test code to run.

If your site is reachable from the internet, there is nothing to decide — the default **cloud** target just works.

## Quick Decision Guide

| Situation                                                         | Execution target                                                                                                                           |
| ----------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
| Your target site is public or a normal staging URL                | **Cloud** — runs work out of the box in an [isolated sandbox](/runners/what-are-runners.md).                                               |
| Your app is private, and you'd rather not host any runner         | **Tunneled** — connect a [tunnel device](/account-settings/tunnel-devices.md) inside your network; the sandbox reaches the app through it. |
| Your app is private and its traffic must never leave your network | **Private runner** — host the [runner](/runners/self-hosted-runners.md) inside your firewall.                                              |
| The site is on `localhost` of your own machine                    | **Tunneled** — run the `tvtunnel` agent on that machine so the sandbox can reach it.                                                       |

## Cloud vs Tunneled vs Private Runner

|                                  | Cloud (default)             | Tunneled                       | Private runner          |
| -------------------------------- | --------------------------- | ------------------------------ | ----------------------- |
| Where test code runs             | TestVibe's isolated sandbox | TestVibe's isolated sandbox    | Your own infrastructure |
| What you install                 | Nothing                     | The small `tvtunnel` agent     | The runner image        |
| App reachable from the internet? | Required                    | Not required                   | Not required            |
| App traffic                      | Direct from the cloud       | Relayed (encrypted end-to-end) | Stays in your network   |
| App URL                          | Unchanged                   | Unchanged                      | Unchanged               |

{% hint style="info" %}
**Tunneled vs private runner for private apps.** Both let you test an app the internet can't reach. With a **tunnel**, the untrusted AI-generated test code stays in TestVibe's sandbox and only a small signed agent runs on your side. With a **private runner**, that test code runs on your own infrastructure — so review and approve generated tests before running them there.
{% endhint %}

## What To Check

| Check                                                | Why it matters                                                                           |
| ---------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| Can you open the site URL from outside your network? | If yes, the cloud target works — no setup needed.                                        |
| Is the URL private or internal?                      | Use a tunnel device or a private runner.                                                 |
| Must the app's traffic stay inside your network?     | Use a private runner; nothing transits TestVibe.                                         |
| Is the tunnel device or private runner online?       | Offline devices and runners can't accept runs; runs against private apps will not start. |

## Next Step

* Public app: nothing to do — start a run.
* Private app via a tunnel: see [Tunnel devices](/account-settings/tunnel-devices.md), then [Set a project's execution target](/runners/set-default-runner.md).
* Private app on your own infrastructure: see [Private runners](/runners/self-hosted-runners.md).

## Related Help

* [What are cloud sandboxes?](/runners/what-are-runners.md)
* [Private runners](/runners/self-hosted-runners.md)
* [Troubleshoot execution](/runners/troubleshooting-runners.md)


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.testvibe.com/runners/choose-a-runner.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.