GET

/v1/schemas/fal/image/blackforestlabs/flux-3/klein/edit-image

kind inputactivity imagehash 8b225af7…extracted Oct 16, 2026version currentsource upstream spec ↗
fieldrecorded source
schemaSource linked above.

upstream-spec

Source trace
ccab0cb98c522cf85494585eaa6e949964b1d98469269e72f60fcfc60a82c8ce
{
  "fetchedAt": 1792126843,
  "extractorVersion": "1",
  "verifiedAt": null
}

Request body

10 properties · 2 required · 3 $defs
propertytypedescriptionconstraints
prompt*stringA complete caption of the target image with the edit folded in. Refer to the references by their order: the first image, the second image.
image_urls*string[]The reference images to edit or compose from (up to 10).items ≥ 1 · items ≤ 10
image_sizeImageSize | enumThe size of the generated image, 256 to 4096 pixels per side. If not set, a single reference image's own size (scaled to at most 4 megapixels) is used, or the first reference image's size (at most 1 megapixel) when several are given.nullable
seedintegerThe same seed and the same prompt given to the same version of the model will output the same image every time.nullable
sync_modebooleanIf `True`, the media will be returned as a data URI and the output data won't be available in the request history.default: false
bounding_boxesEditBoundingBox[]Optional layout, with (0, 0) at the top-left of each image: keep, move, resize or remove objects from the references, or place new ones. Name boxes in the prompt by label, e.g. `<dragon>`.items ≤ 32 · nullable
num_imagesintegerThe number of images to generate.1 ≤ n ≤ 4 · default: 1
output_formatenumThe format of the generated image.jpeg | png | webp · default: "png"
enable_prompt_expansionbooleanIf set to true, the prompt is expanded into a detailed caption (grounded in the reference images when editing) before generation.default: true
enable_safety_checkerbooleanIf set to true, the safety checker will be enabled.default: true

Types

3 $defs

Boxobject

y_max*numberBottom edge as a fraction of the image height (0-1).0 ≤ n ≤ 1
x_min*numberLeft edge as a fraction of the image width (0-1).0 ≤ n ≤ 1
x_max*numberRight edge as a fraction of the image width (0-1).0 ≤ n ≤ 1
y_min*numberTop edge as a fraction of the image height (0-1).0 ≤ n ≤ 1

EditBoundingBoxobject

boxBoxWhere the object goes in the output image, as on text-to-image. Use instead of `source_box`/`target_box`.nullable
description*stringWhat to draw in this box: the object and its look.length ≤ 500
source_boxBoxWhere the object is in the reference image. Requires `source_image_index`.nullable
source_image_indexinteger0-based index into `image_urls` of the reference the object comes from. Leave unset for a new object.n ≥ 0 · nullable
labelstringShort name for the object in this box, e.g. `dragon`. Write `<dragon>` in the prompt to tie the box to those words; a box the prompt doesn't name is added to the scene. Defaults to `obj_<n>`.length ≤ 64 · nullable
target_boxBoxWhere the object goes in the output image. Leave unset to remove a referenced object; set both boxes to move or resize it.nullable

ImageSizeobject

heightintegerThe height of the generated image.0 < n ≤ 14142 · default: 512
widthintegerThe width of the generated image.0 < n ≤ 14142 · default: 512

Validate a payload

before you spend tokens
shell
$ curl -X POST https://modelschemas.com/v1/validate \
    -d '{"provider":"fal","endpointId":"blackforestlabs/flux-3/klein/edit-image","payload":{…}}'
→ {"valid": false, "errors": [{"path": "#", "keyword": "required", …}]}