Video API callback_url and Idempotency-Key: a sume/auto job in curl

To avoid polling, add an HTTPS callback_url to the POST /v1/videos body and Sume will POST to it when the job reaches a terminal state. Add an Idempotency-Key header so a retry returns the original job instead of creating and charging a second one.

With model: "sume/auto", Sume chooses the model from the request. The default target is Gemini Omni Flash 1.1, with 3 to 10 second clips at 360p to 4K in 16:9 or 9:16.

The request

The prompt, duration and ratio below fit the Auto envelope. The default is 720p and 8 seconds when you omit them.

curl -X POST "https://api.sume.com/v1/videos" \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: ad-spring-001" \
  -d '{"model":"sume/auto","prompt":"A vertical UGC-style product clip on a desk, natural light","aspect_ratio":"9:16","duration":6,"callback_url":"https://example.com/hooks/sume-video"}'

What to rely on

Sume signs the raw JSON body and sends x-sume-webhook-timestamp and x-sume-webhook-signature headers. The payload is Sume's standard job webhook envelope, not an OpenRouter video.generation.* event. Follow the verification steps in the API reference and refuse to run the check if your signing secret is empty.

A webhook can be delayed or lost, so treat it as a nudge and confirm with GET /v1/videos/{id} before you act on the result. The same job is also readable at GET /v1/jobs/{id}/status and /result.

Auto's limits

Auto validates against the Omni 1.1 envelope and fails closed. A 2-second or 11-second duration, 480p, or generate_audio: false returns 400 unsupported_capability, and the error names sume/auto, not an underlying model. If you need a longer clip or silence, pin a catalog id instead.

Auto does not appear in GET /v1/videos/models, because it is a routing value, not a model.

• Longer than 10 seconds: pin wan-3.0, seedance-2.5, kling-3 or an H3 row.
• Silent output: pin kling-3 and send generate_audio: false.
• Retry on 429 or 5xx with the same Idempotency-Key.