GET

/v1/schemas/fal/video/kling/v4/flash/video-to-video

kind inputactivity videohash 61271f9d…extracted Nov 5, 2026version currentsource upstream spec ↗
fieldrecorded source
schemaSource linked above.

upstream-spec

Source trace
e3efafa8189b7961f6b3e0b88cb0c6795ead4addad7fb4178d20a9a5a6d1245f
{
  "fetchedAt": 1793854802,
  "extractorVersion": "1",
  "verifiedAt": null
}

Request body

7 properties · 2 required · 1 $defs
propertytypedescriptionconstraints
prompt*stringEdit instruction. Reference the source video as @Video1.length ≤ 26000
video_url*stringThe video to edit (3-20s), referenced as @Video1.
video_urlsstring[]Reference videos, referenced as @Video2, @Video3, ... (max 4). The source, reference and element videos must total at most 20s.items ≤ 4 · nullable
elementsKlingV4FlashElement[]Characters/objects, referenced as @Element1, @Element2, ... (max 7). Up to 3 may be video elements. Flash does not accept voices.items ≤ 7 · nullable
durationintegerOutput duration in seconds (3-20). Defaults to the source video's length.3 ≤ n ≤ 20 · nullable
image_urlsstring[]Reference images, referenced as @Image1, @Image2, ... (max 10).items ≤ 10 · nullable
resolutionenumOutput resolution. Flash is 720p only.720p · default: "720p"

Types

1 $defs

KlingV4FlashElementobject

A Kling 4.0 element without a bound voice; Flash takes no voices.

frontal_image_urlstringThe frontal image of the element (main view).nullable
reference_image_urlsstring[]Additional views of the element from different angles (1-3).items ≤ 3 · nullable
video_urlstringA video of the element, used instead of images (3-8s).nullable

Validate a payload

before you spend tokens
shell
$ curl -X POST https://modelschemas.com/v1/validate \
    -d '{"provider":"fal","endpointId":"kling/v4/flash/video-to-video","payload":{…}}'
→ {"valid": false, "errors": [{"path": "#", "keyword": "required", …}]}