AI features draw on a monthly AI budget included with your plan. It resets every month.
On per-seat plans the budget is pooled across the workspace, so a heavy user and a light user balance out rather than each hitting a personal wall.
Anything the AI does: asking Dana, an agent answering or drafting, AI steps inside automations, and AI autofill on a field, where each row it fills is one AI run.
Ordinary work uses none of it. Creating records, views, dashboards, forms, automations without AI steps, formula fills, and everything else in Atwork is unaffected.
The workspace owner sees usage on the AI usage page: open your profile menu, choose Administration, then AI usage under Billing. Worth a look in the first month of using agents heavily, so a surprise is a decision rather than a surprise.
The page shows:

Everyone can see their own spend: open your profile menu, choose Preferences, then AI usage.
The bolt in the header shows how much AI budget is left, your monthly allowance and top-up credit together, out of the total. It appears only when 10% or less is left: orange while some remains, red once it is used up. Click it to open your own AI usage.
AI features stop until there is budget again. Dana shows AI budget used up instead of a reply: the workspace owner gets a View AI usage button, and everyone else is asked to contact the owner to top up or upgrade. A fill of existing rows stops with Stopped: out of AI credit, keeps the rows it already filled, and shows a Buy AI credit link. The budget comes back at the monthly reset, or straight away when the owner buys credit.
Buy AI credit. A top-up is a one-off purchase of credit on top of your monthly budget, and it works on every plan, Free included. Only the workspace owner can buy it.
Your monthly budget is used first, and top-up credit only after it runs out. Purchased credit never expires: it carries through the monthly reset, a plan change and a cancellation. Amounts, receipts and what to do if the credit doesn't show up are in Payment methods and AI credit top-ups.
Upgrading raises the per-seat budget, and Enterprise sets it to whatever you need. If you are topping up every month on Pro, that is the signal.
Related: Plans & billing explained · Meet Dana, your AI assistant · What is an agent? · Fill a field automatically