FLUX.1 Kontext pro vs FLUX.2 for edits: what to use on Sume
BFL calls FLUX.1 Kontext [pro] previous-generation and recommends FLUX.2 for edits with up to 10 references. On Sume, use flux.2-pro with input_references.

For a new edit workflow, use FLUX.2. BFL's Kontext page calls FLUX.1 Kontext [pro] a previous-generation model and says FLUX.2 is now its recommended model for generation and editing. On Sume, send black-forest-labs/flux.2-pro with input_references, and I found no Kontext id in the Sume image catalog.
Vendor statements are from the BFL page, read 2026-10-01. Sume rules are from the Image API docs.
What does BFL recommend?
The page leads with a note that FLUX.2 offers multi-reference support for up to 10 images, improved text editing and output up to 4MP. It describes Kontext [pro] as combining text-to-image and image editing, with prices of $0.04 per image for [pro] and $0.08 for [max] on that page.
| Model | Status on BFL page | Stated capability |
|---|---|---|
| FLUX.1 Kontext [pro] | Previous-generation | Text-to-image plus editing |
| FLUX.2 | Recommended for new projects | Up to 10 references, up to 4MP output |
How do references work on Sume?
input_references is an optional array of reference images for image-to-image. Reference URLs must be public HTTPS; localhost, private-network and non-HTTPS URLs are rejected before submission. Models whose input_references descriptor is min 0 and max 0 are text-to-image only and reject references, so read the descriptor on the catalog row before sending.
For a worked request, see FLUX.2 multi-reference editing.
Is the reference cap the same on Sume?
Do not assume it. The docs say per-model ceilings are published as capability descriptors on the catalog, and the examples there show a max of 10 for some rows. Read the input_references max for the exact model you call.
What should I do with an existing Kontext prompt?
Keep the instruction text, move your source images into input_references, and switch the model id to black-forest-labs/flux.2-pro. Test a handful of edits before cutting over, because prompts tuned for one model may need rewording on another.
Sources
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