Runway multi_shot_video at 13 credits per second vs Sume clips

Runway's API pricing page lists a multi_shot_video recipe at 13 credits per second at 720p and 17 at 1080p. At $0.01 per credit, a 15-second result is $1.95 at 720p or $2.55 at 1080p. Sume has no single multi-shot call: you generate each shot with POST /v1/videos and join them with Timeline, at $0.10 per output minute. Three 5-second seedance-2-mini shots at 720p come to $2.95 before the agent fee.

Runway facts are from its pricing page, read 2026-10-01. Sume facts are from the video docs and Timeline docs; clip figures come from the pricing code. This compares prices only, not what each path produces.

What does Runway's recipe cost for 15 seconds?

The recipe is billed per output second, so the cost scales with length and resolution. The page lists no minimum for it in the lines read.

What do three Sume shots plus a join cost?

Each 5-second shot reserves the model's list price times 1.25. Timeline then bills one minute for any output up to 60 seconds. A 5.5% agent fee applies by default on top of every row.

How do I join the shots on Sume?

Generated clips are already hosted on Sume's media domain, which Timeline requires. Use audio.mode: "silence" when the shots carry their own sound, and set each slot's start on the timeline.

curl -X POST https://api.sume.com/v1/timeline-1.0/render \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: three-shots-001" \
  -d '{
    "audio": { "mode": "silence", "duration_seconds": 15 },
    "video": [
      { "source_url": "https://media.sume.com/artifacts/artf_demo/shot1.mp4", "start": 0, "duration": 5 },
      { "source_url": "https://media.sume.com/artifacts/artf_demo/shot2.mp4", "start": 5, "duration": 5 },
      { "source_url": "https://media.sume.com/artifacts/artf_demo/shot3.mp4", "start": 10, "duration": 5 }
    ]
  }'

Is there a cheaper way to try a multi-shot idea?

Draft the shots at 480p first, then regenerate only the ones you keep; the Seedance 2.5 draft workflow shows the pattern. You can also run POST /v1/timeline-1.0/plan on the join first, which is unbilled.