Kling 3.0 in the Sume Videos panel: 5-15 s choices vs API 4-15 s

Which durations does the Sume panel offer for Kling 3.0?

Five: 5, 6, 8, 10 and 15 seconds. That is the list in the panel's control definition for Kling 3.0, alongside aspect ratios of 16:9, 9:16 and 1:1 and an audio toggle.

The API row is wider. The kling-3 catalog entry accepts whole seconds from 4 to 15, so 4, 7, 9, 11, 12, 13 and 14 are valid API requests that the panel does not present.

Why is there no end frame in the panel?

The panel's Kling 3.0 definition sets end-frame support to false, with a code comment noting that the product path does not expose an end or tail frame for create. The API does: the catalog lists end_frame: true and supported_frame_images as first and last frame, with the rule that a last frame must come with a first frame.

So a looping clip or a defined landing pose is an API job today. The first and last frame guide shows the request shape.

What about the 4K option?

The panel shows a 4K label for Kling 3.0, but the API row stops at 1080p, and a 4K request against kling-3 is rejected as not advertised. Rather than repeat the detail here, read the 4K option explainer, which covers what the panel submits.

How do I pick the length for a 7 second idea?

Either round up to 8 in the panel and trim, or call the API with duration: 7. Trimming a longer clip is cheap to reason about because the reserve on submit scales with seconds: the workspace balance is held at the provider list rate times 1.25, and the finished job reports the Sume billable amount in usage.cost.

If the exact second matters for lip-sync or a beat in the music, request it directly through the API instead of trimming.

curl -X POST "https://api.sume.com/v1/videos" \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "kling-3",
    "prompt": "A paper boat drifts across a rainy street, slow tracking shot",
    "duration": 7,
    "resolution": "720p",
    "aspect_ratio": "1:1"
  }'

How do I keep the two surfaces from drifting apart?

Treat GET /v1/videos/models as the source of truth for limits and the panel as a convenience view of it. When a number in the panel and a number in the catalog disagree, the catalog is what the API enforces. Pin kling-3 explicitly in code, because Auto does not disclose which family served a clip, and read Kling 3 duration and aspect limits for the full envelope.