Threads podcast video highlight: cut the clip with video trim

Meta's Threads podcast toolkit lets you broadcast highlights as transcript, video and guest card posts. To make the video post from a full episode file, cut the standout moment with Sume POST /v1/video-trim: it returns a new MP4 holding only [start, end), at $0.02 per job.

Threads details are from Meta's announcement; trim details from Video trim, read 2026-10-01.

Where does the highlight video come from?

Meta's announcement says under "Broadcast the highlights" that you can share standout moments with video posts, and gives no length or format rules for them in that text. Check the Threads composer for limits; Threads video upload limits covers that separately. Your job is the cut itself: pick a start time from the episode and a length.

How do I cut the highlight?

Send the source, an in-point start in seconds, and exactly one of end or duration. The source must already be a media.sume.com clip: there is no open-internet fetch, so import first with POST /v1/media-imports. An Idempotency-Key is required.

curl -X POST https://api.sume.com/v1/video-trim \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: threads-highlight-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/episode.mp4",
    "start": 1325.5,
    "duration": 45
  }'

What are the limits?

What if the source is longer than 1800 seconds?

It fails with source_duration_exceeded. A very long episode needs to be split before import. The result's video_url is a new artifact, never the source, and actual_start_seconds tells you where a keyframe-mode cut really began; with the default exact precision the cut is a frame-accurate re-encode.