Cancel a Sume Omni job: only before it starts, then 409

On Sume you can cancel a video job only while it is still queued. POST /v1/jobs/{job_id}/cancel before generation work starts cancels it and releases the reservation. After it starts, the call returns 409 job_generation_already_started with details.cancelable: false, and the job completes or fails normally, so a 4K Omni clip you regret still costs $3.75 for ten seconds if it completes (provider list $0.30 per second times 1.25). Cancelling an already canceled job is idempotent.

What the docs state

The cancellation section of Generation admission says paid generation reserves the estimated amount when the request is accepted, captures it on success, and releases or refunds it on failure or failed admission. Cancel is listed as a way to free queue room: when you hit queue_full, cancel queued jobs you no longer need.

The Video Router rate for Omni is provider list times 1.25 per output second. The dollar figures below use the $0.10 per second list rate for 720p and $0.30 for 4K from Sume's pricing code, times 1.25.

Patterns that follow

• Submit expensive settings last. Run a 3 second 360p proof first, then the 4K clip, so a wrong prompt wastes cents instead of dollars.
• Do not submit a full batch and plan to cancel; with 4 running at once on Pro, only the queued tail is cancelable.
• On queue_full, cancel stale queued work, then retry with the same idempotency key.
• Treat a 409 on cancel as information: record that the job will finish and let it.

Compared with Google

Google's pages I read do not describe cancelling an in-flight Omni generation, and I make no claim about it. Google lists the Gemini API price per output second of video on its pricing page. Whichever route you use, the safest control is not to start the wrong job; check the prompt and the resolution before you submit.