> ## Documentation Index
> Fetch the complete documentation index at: https://docs.citino.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Engines and opt-ins

> Which AI engines every project is asked on, which ones you can switch on, and where the switch is.

An engine is an AI answering surface your buyers use, such as ChatGPT or Google's AI Overview. Every engine a project tracks is asked every one of its questions, every day.

> The country we ask from and the AI engines we ask. Each engine is asked every question.

## The three defaults

**ChatGPT**, **Google AI Overview** and **Perplexity** collect for every project, on every plan, from the day the project is created.

## Opt-ins

**Gemini**, **Google AI Mode** and **Claude Haiku** are on every plan and off until you switch them on for a project.

* Switching one on needs a paid subscription. During the trial the row reads "On your plan once your subscription is paid".
* Only an owner or admin can switch one on. An editor can keep one that is already on, or switch it off.
* A workspace can have up to six extra engines switched on at once, across all its projects.
* An extra engine collects from the next daily collection after you save.
* An extra engine's answers are collected and kept, but no screen counts or lists them: every figure and chart covers the default engines you have on. Its answers and figures are available only through the API's `engines` filter.

If the subscription stops being paid, or moves to a plan without that engine, it stops collecting at the next nightly check. What it already collected is kept.

## Enterprise only

**Claude** (Sonnet), **Grok** and **Claude Opus** are available on Enterprise plans only. Project settings lists them with "Enterprise only". [Contact us](https://docs.citino.ai/guides/help/contact.md) to talk about Enterprise.

## Not tracked

**Microsoft Copilot** is not tracked. Its answers can only be read signed in, and we collect every answer signed out. In [Attribution](https://docs.citino.ai/guides/screens/attribution.md), visits that come from Copilot, Claude or Grok are counted and labelled "not sampled" rather than dropped.

## Switching an engine on or off

**1. Open Project settings**

Open the project and choose **Project settings** in the rail.

**2. Go to Market & engines**

Each engine has a switch and one line on its state, such as "Running your prompts", or why it cannot be switched on.

**3. Save**

Save the settings. The change applies from the next daily collection.

Switching an engine off stops future runs of your prompts against it. Its answers are kept, but every figure counts only the engines switched on, so its history leaves the charts while it is off and returns if you switch it back on.

You can switch off a default engine too. Every screen's scope line names the engines its numbers are counted over.

## The market

Next to the engines, Project settings shows the project's market: "Set when your prompts were created. Prompts run from this market's location; a second market is a second project." Today every project asks from the United States, in English.

## Related

> [card] [Project settings](https://docs.citino.ai/guides/screens/project-settings.md)
>
> Everything else on the screen the switches are on.

> [card] [Plans and prompt limits](https://docs.citino.ai/guides/account/plans-and-limits.md)
>
> What each plan includes.

> [card] [How answers are collected](https://docs.citino.ai/guides/methodology/collection.md)
>
> How each engine's answer reaches us.

> [card] [What we do not measure](https://docs.citino.ai/guides/methodology/what-we-do-not-measure.md)
>
> The engines and answers outside our sample.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.