num_images 1-4 or n 1-10? Images per call on Sume's image APIs
Image 1.0 takes num_images 1 to 4. POST /v1/images takes n up to 10, with lower per-model ceilings. Which to use and how to read the real limit.
Image 1.0 accepts num_images as an integer from 1 to 4, while POST /v1/images accepts n from 1 to 10 with per-model ceilings that can be lower. The Image API docs say to read the n range descriptor from the catalog for the real limit.
Read from Sume's Image 1.0 and Image API docs on 2026-09-30.
What are the two limits?
The two routes name the field differently and cap it differently.
| Route | Field | Range |
|---|---|---|
POST /v1/image-1.0/generate | num_images | 1 to 4 |
POST /v1/images | n | 1 to 10, per-model ceiling may be lower |
How do I find a model's real ceiling?
Each model's supported_parameters carries n as a range descriptor, for example { "type": "range", "min": 1, "max": 4 } in the Seedream 4.5 sample in the docs. That sample is an illustration; call the endpoint for the live value.
curl "https://api.sume.com/v1/images/models/bytedance-seed/seedream-4.5/endpoints" \
-H "Authorization: Bearer $SUME_API_KEY"What does it cost to ask for more?
Endpoint pricing lines are what is charged, so cost_usd x n is the bill for a call with n images. Large n, 4K and high quality are the configurations most likely to run past the 30-second wait and return 202 with a job envelope instead of the images.
What if I ask for too many?
A value outside the descriptor's range is not a documented soft clamp; stay within the listed range and split larger sets into several calls.
How do I check this myself?
For very large sets, prefer many small requests over a single large n, so one slow generation does not turn the whole call into a 202 job. Use metadata to tie them back to your records. The linked docs pages and the catalog endpoint show the current values, and this post reflects them as of 2026-09-30.
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