# How credits are used

> See what uses credits in TulipFarm, where to check your workspace balance, and what happens when the credits run out.

Source: https://docs.tulipfarm.ai/billing/

TulipFarm uses [credits](https://docs.tulipfarm.ai/concepts/credits/) to measure AI model usage. This section explains what uses credits, where to see your balance, and what happens at zero.

## What uses credits

Only AI model calls use credits. These actions make model calls:

- Replies in chat
- Agent tasks
- [Knowledge](https://docs.tulipfarm.ai/concepts/files-and-knowledge/) search
- **Ask AI** search in tables
- Replies from [Bud](https://docs.tulipfarm.ai/getting-started/meet-bud/)

Tool calls and other computing do not use credits.

Different models cost different amounts. The **Models** page shows the input and output credits per million tokens for each model. A token is a small piece of text that a model reads or writes.

## Where to see your balance

1. Select the workspace name in the top-left corner.
2. Select **Settings**.
3. Select **Usage**.

The **Balance** section shows:

| Item | What it is |
| --- | --- |
| Credits left | The credits that the whole workspace can still use. |
| **Used** | The credits already charged. |
| **Reserved** | The credits held for model calls that are not settled yet. |
| **Welcome credits** | The free credits that the workspace started with. |

Below the balance, you can split usage by model, by agent, or by activity.

- Admins see the usage of the whole workspace, including each agent by name.
- Members see their own chats and the agents they can open. Other people's activity stays private.

## What happens at zero

When the workspace has no credits left:

- New chats are blocked.
- Replies are blocked.
- Agent model steps are blocked.
- Existing messages stay readable.

A balance above zero can still be too low for a large model. The model call then does not start.

> **Note:** There is no self-serve top-up. To get more credits, contact TulipFarm support.

## In this section

  - [Get more credits](https://docs.tulipfarm.ai/billing/get-more-credits/): Contact TulipFarm support to add credits to your workspace.