Luma Agents API presigned URL, generation id and Sume job ids

Luma's guide says presigned video URLs expire after 1 hour, while the generation id does not, and a fresh URL is available by polling the generation again. The durable thing to store is the id. On Sume the equivalent is the job id: keep it, read the job again, and treat artifact URLs as opaque.

Luma details are from its guide, read 2026-10-01. Sume details are from Video 1.0 and Video generation.

What does Luma say expires and what does not?

The note reads: presigned URLs expire after 1 hour, so download to your own storage promptly or re-poll GET /v1/generations/{id} to mint a fresh URL. The generation id does not expire, so keep it if you plan to edit, extend or reframe the video later.

What do completed Sume jobs return?

Completed Video 1.0 jobs return Sume-hosted video artifacts, each with an id, a type, a URL and a content type such as video/mp4. The docs say to treat artifact URLs as opaque and not to parse paths for workspace, job or provider identifiers. The video API also lists unsigned_urls once a job is completed.

What should I store?

Store the job id, not a URL. When you need the file again, call the job route and read the current result. If you need your own copy, download it when the job completes and keep it in your storage. The Sume pages I read do not state a URL lifetime, so do not assume one either way. For why polling twice is safe, see the earlier note on Luma URL expiry.

What about extending a clip later?

Luma uses the prior generation id for extension. Sume's model is a new job per clip, so keep the earlier job id next to the new one in your own records. See Luma Ray 3.2 extend vs a new Sume job.