Revert an AI video edit: why Sume trims never touch your source

If you want to undo an AI video edit in a pipeline, the safest design is an edit that cannot overwrite anything. Sume's media tools work that way: POST /v1/video-trim always returns a new artifact (the result says video_url is a new artf_, never the source), so reverting is just using the earlier URL again. No undo stack, no restore call.

Why people ask

Descript's changelog records a Revert button moved into an action bar below Underlord's response, so undoing an AI change is one click in the editor. That is a good answer for a person at a desk. An unattended pipeline has no desk, so the question becomes how to keep every intermediate version addressable.

A version chain that you can revert

Keep a plain list: original URL, then the URL after each step. The step that you dislike is dropped and you carry on from the entry before it.

Because each result is a separate media.sume.com artifact, you can also branch: trim the same original two ways and compare. Run POST /v1/video-filter/check first (unbilled) when the edit is a filter, so a bad program is rejected before it creates an artifact at all.

• Store original, trimmed, filtered and rendered URLs per clip, not just the last one.
• Send an Idempotency-Key built from the clip id and a version number, so a retry returns the same artifact instead of a second charge.
• Treat a timeline render as the last step; it reads artifacts and writes a new video, so earlier versions remain.

An example chain

For one clip the chain might read: original, trimmed, filtered, captioned, rendered. Each entry is a URL you hold. If the filter looks wrong, you go back one entry and apply a different program; the trim is still paid for and still there. That is the whole revert story, and it is why intermediate URLs are worth saving.

Limits

Sume has no undo for a generation you already paid for; the cost of a rejected result is the job price. Artifacts are yours to keep, but Sume's docs do not promise indefinite retention, so copy the ones you need to your own storage. And this is an API property, not an editor: if you want a visual revert button, the editor is where Descript is stronger.