Are flat Sume timeline, trim and filter prices ceilings or fixed fees?

Is a flat price on a Sume ffmpeg tool a fixed fee?

Treat it as a reserve ceiling. Sume's API contract describes these tools as reserved at the listed price and captured at the pass's own Modal compute (list price times 1.25 plus the platform fee), never above the reservation.

So the listed figure is the most the job takes. It is not a promise that every job lands exactly on that number, and Sume's docs do not publish a lower typical figure, so budget with the listed price.

What are the flat prices?

From the rate card.

Which related calls cost nothing?

Several preflight calls are unbilled: the video-filter check, timeline plan, video-frames, the reference-ingest manifest and the Hypit probe, boundaries, tile and cut calls. Use them to confirm the job before you pay for it. The timeline plan post and the filter check post show how.

How should I budget with ceilings?

Add the listed price for each step. A pipeline of one trim, one filter and one 3-minute timeline render budgets at $0.02 + $0.02 + $0.30, or $0.34. Your real charge can be lower, but you cannot rely on that, and Sume's docs do not state by how much.

Read the final figure from the usage summary after the job, using the debited amount.

Does Sume refund the difference between reserve and capture?

The capture happens at actual compute and never above the reservation, so the balance you see after completion reflects the captured amount. Failed or pre-generation-canceled jobs are refunded. See the timeline docs for the render limits.

What does a pipeline budget look like?

A shop makes a 30-second ad from phone clips. It trims two clips at $0.02 each, runs one filter at $0.02, composes at $0.02 and renders a 1-minute timeline at $0.10. The ceiling total is $0.18.

Add captions at $0.20 and the pipeline budget is $0.38. Those are reserve ceilings, so the real total can only be lower or equal on the flat ffmpeg steps, though Sume's docs do not say by how much.

Run the free checks first, since a bad filter or plan costs nothing to find out, while a wasted render still costs its reserve.