Pricing
Every template has anestimated_credits cost, set when it’s saved. A request costs template.estimated_credits × row_count — for a single video, that’s just template.estimated_credits.
You never send a cost figure in a request — it’s always computed server-side from the template itself, so a caller can’t under-report their own cost.
When credits are charged
Credits are deducted before rendering starts, at the moment a request is accepted (the202 Accepted response).
Insufficient credits
If the workspace’s account doesn’t have enough balance, the request is rejected before anything is created or dispatched:402 Payment Required