Docs/Billing

What you are charged when

Which outcomes cost credits, and which do not?

Checked against the code on

The rule is simple: you pay when the model ran. The table is the rule applied to every outcome.

OutcomeCharged
Reply completedThe real cost of the tokens (or the picture, or the clip)
Stream stopped by you part-wayWhat was generated up to that point
Reply came back emptyNothing. An empty reply is an error, not an answer.
Model refused the request (502 rejected)Nothing
Model access unavailable (503)Nothing
Too many requests (429)Nothing
Not enough credits (402)Nothing. The request never ran.
Model ran but the reply was unreadable (502 unreadable)The reservation. It was billed upstream.
Model ran past the 120 s deadline (504)The reservation. It was generated and billed upstream.
Video render failedNothing. The hold is released.
Video render completedThe published price shown before you started

The two charged failures are rare and both mean the model did the work. Lowering max_tokens shrinks what the reservation can be.