# Models and AI usage

> Choose the model cherry answers with, see what AI costs in the top bar, and know what happens when the daily AI limit is reached.

cherry runs on an AI model, and every call to one is billed to your workspace. You choose which model answers, owners and admins choose which models are on offer, and a daily limit stops spend running away.

## Choose a model

At the foot of the box you type in, the model button shows the model cherry will use for this conversation. Press it to open the list.

Each option shows a **tier**, which says what the model is for, and a **cost hint**:

| Tier | What it suits |
|---|---|
| best | The deepest reasoning: wide schemas, long setups, questions that need several joins |
| balanced | Everyday questions and building |
| fast | Direct lookups, at the lowest cost. Thinner on multi-step reasoning |

The cost hint runs from lowest to highest, and it is relative: a rough guide to which options spend more of your daily limit for the same conversation.

Your choice applies to the conversation you are in, and is remembered in your browser for the next new one. If you have not chosen, a new conversation starts on your workspace's default. You can switch models part way through a conversation, and the next reply uses the new one.

Some AI work is not run by the model in the picker. The passes that learn your data, for example, run on a model sanda chooses. They are still billed and still count towards your daily limit.

## Which models are on offer

Owners and admins choose the models under **Settings · cherry**, in the panel **cherry · models**.

- Switch on up to five models. They are what appears in the picker. At least one must stay on.
- Press **make default** on one of them to set the model new conversations start on.
- Each model shows its tier and its price per million tokens in and out, before sanda's AI markup, so you can compare them. Where the price is not available, it shows the cost hint instead.
- A model marked **not listed by the provider** is switched on but may no longer exist. Switch it off.

Members and viewers can use the picker but cannot change what is on it.

## The daily AI limit

Every workspace starts with a daily AI limit of A$5. Owners and admins can set their own, up to A$50 a day. If you need more than that, contact sanda support.

To change it, go to **Settings · Plan & budget**, open **Budget & alerts**, and set **Daily AI limit (AUD)**. Leave the field empty to use the default. A limit of 0 switches AI off for the workspace.

The limit counts every AI call sanda makes for your workspace: cherry, the passes that learn your data, suggestions, drafts, and search indexing and searches. Syncs and scheduled reports are not counted. It resets at midnight UTC, which is 10am in Sydney during standard time and 11am during daylight saving.

## Watch the meter

The ring in the top bar shows how much of today's limit you have used, and on a wide screen the figure beside it shows today's spend. Press it to open **AI today**:

- today's spend against the limit, in a bar that turns amber as you near the limit and red when you reach it;
- **This month**, the AI you will see on your invoice, which is billed with storage and compute;
- **Today by model**, what each model has cost so far today;
- your limit, and whether it is your own or the default;
- when it **Resets**;
- links to **Change the limit** and **Change model**.

The meter updates as cherry works, so you can watch a long reply spend. The figure under each reply is what that reply cost, in the same billed dollars, so the two agree.

## Every AI call is billed

Each call is charged at cost plus sanda's AI markup, in Australian dollars, and appears on your invoice with storage and compute. Nothing is free, though a trial's free credit pays for its first AI use. See [usage and billing](https://docs.sanda-os.com.au/billing/usage) and [budgets and limits](https://docs.sanda-os.com.au/billing/budgets-and-limits).

Even the small call that names a new conversation is billed.

Ways to spend less:

- Start a new chat when you change topic. A long thread sends more of its history with every message.
- Use a **fast** model for lookups and a **best** one for hard modelling.
- Ask for a top ten, or for a report, instead of a long list.

## What happens at the limit

When the workspace reaches its limit:

- cherry stops, in the middle of a reply if need be, and says so: the workspace has reached today's AI limit, it resets at midnight UTC, and an owner or admin can raise it under **Settings · Plan & budget**. Your next message gets the same answer until then.
- Other AI work waits, including learn from my data, suggestions and drafts.
- Search index builds pause and pick up where they stopped. Search itself still answers, from matching words only.
- **Syncs, reports and your data are not affected.**

If alerts are on under **Settings · Plan & budget · Budget & alerts**, sanda emails the alert recipients once a day when the limit is reached. The setting is **When the day's AI limit is reached**.

On a trial, AI is paid for from the trial's free credit first. Once the A$10 is spent, the workspace is frozen until an owner or admin moves it to a paid edition. Your data is kept.

:::links
- [Actions and approvals](https://docs.sanda-os.com.au/cherry/actions-and-approvals): How to keep changes under control.
- [Budgets and limits](https://docs.sanda-os.com.au/billing/budgets-and-limits): The monthly budget beside the daily limit.
- [Usage and billing](https://docs.sanda-os.com.au/billing/usage): Where AI appears on your invoice.
:::