Use FLUX 3 Video with Comfy Router

API Reference for FLUX 3 Video. FLUX 3 Video is Black Forest Labs’ video generation model, turning a text prompt into a short clip with synchronized audio.

Comfy Router is not generally available yet. POST /v2/models/{provider}/{model} and its catalog and schema siblings are not serving requests yet: an authenticated call answers 404 today. The snippets on this page document the contract those routes will serve, published ahead of the rollout so your integration is ready to write against.

Quick start

Create a key at platform.comfy.org/profile/api-keys and export it as COMFY_API_KEY. The Python and TypeScript snippets use the Comfy SDKs (pip install comfy-sdk, npm install @comfyorg/sdk); the cURL snippet is the same call over raw HTTP. Model ID: bfl/flux-3-video Endpoint: POST https://api.comfy.org/v2/models/bfl/flux-3-video

from comfy_sdk import Comfy

# Reads COMFY_API_KEY from the environment. Each call sends a fresh
# Idempotency-Key and waits up to 10 minutes for the finished result.
with Comfy() as client:
    result = client.models.run(
        "bfl/flux-3-video",
        {
            "mode": "t2v",
            "prompt": "a single red maple leaf falling onto still water, slow motion",
            "duration": 5,
            "aspect_ratio": "16:9",
            "generate_audio": True,
        },
    )

print("video:", result["result"]["sample"])

import { comfy } from "@comfyorg/sdk";

// Reads COMFY_API_KEY from the environment. Each call sends a fresh
// Idempotency-Key and waits up to 10 minutes for the finished result.
type Result = { result: { sample: string } };
const { data } = await comfy.models.run<Result>("bfl/flux-3-video", {
  mode: "t2v",
  prompt: "a single red maple leaf falling onto still water, slow motion",
  duration: 5,
  aspect_ratio: "16:9",
  generate_audio: true,
});

console.log("video:", data.result.sample);

curl https://api.comfy.org/v2/models/bfl/flux-3-video \
  -H "X-API-Key: $COMFY_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d "{\"mode\": \"t2v\", \"prompt\": \"a single red maple leaf falling onto still water, slow motion\", \"duration\": 5, \"aspect_ratio\": \"16:9\", \"generate_audio\": true}"

Schema

Input

Fields follow Black Forest Labs’ published API specification and are checked against it in CI. Router’s own schema for this model is not published yet, so requests are forwarded to the provider unvalidated.

string

required

Generation mode: t2v text-to-video, i2v continue from images in keyframes, v2v continue the video in start_video, draft_enhance full-quality render of a prior draft.Possible values: t2v, i2v, v2v, draft_enhance

string

Free-form description of the video. Required in every mode except draft_enhance.

string[]

i2v only. One to ten images (HTTPS URLs or base64) that become frames: one starts the video, two start and end it, more are spread evenly.

string

v2v only. The video to continue, as an HTTPS URL or base64 MP4.

integer | "auto"

default:"\"auto\""

Video length in whole seconds, or auto to fit the content. v2v caps the range at 15 seconds; the other modes accept up to 20.Range: 5 to 20

string

default:"\"auto\""

Output aspect ratio. auto lets BFL choose from the inputs.Possible values: auto, 21:9, 2:1, 16:9, 4:3, 1:1, 3:4, 9:16

string

default:"\"fhd\""

fhd (default) is finished by the video upsampler; hd is faster.Possible values: hd, fhd

boolean

default:"true"

Generate synchronized audio alongside the video.

integer

default:"2"

Moderation tolerance for inputs and outputs. 0 is strictest.Range: 0 to 4

boolean

default:"false"

Generate a fast preview instead of the full render.

string

default:"\"latest\""

Endpoint version. latest serves the current release.

string

draft_enhance only. The draft-cache bundle returned by a prior draft generation.

Output

Router returns Black Forest Labs’ native response unchanged. The video is at result.sample.

string

required

BFL task id for this generation.

string

required

Terminal task status. Router only returns once this is Ready.Possible values: Ready

object

required

string (uri)

required

Signed URL of the generated MP4. Expires roughly two hours after the result is ready.Format: uri

Examples

Input

{
  "mode": "t2v",
  "prompt": "a single red maple leaf falling onto still water, slow motion",
  "duration": 5,
  "aspect_ratio": "16:9",
  "generate_audio": true
}

Output

{
  "id": "0a1b2c3d-...",
  "status": "Ready",
  "result": {
    "sample": "https://.../out.mp4"
  }
}

result.sample is a signed URL that expires roughly two hours after the result is ready. Download the MP4 promptly.

Before you ship

The snippets above are the shortest working call. Three things are the same for every model and are documented once on the Comfy Router headers page: send an Idempotency-Key on every paid call and reuse it when you retry, expect the connection to be held up to Router’s 10 minute deadline, and keep X-Comfy-Request-Id from every response. The SDKs do all three for you; the cURL tab does none of them. On failure, X-Comfy-Error-Type names the bucket, and a 422 means the body failed the model’s schema and was never billed.

Headers

Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.

Quickstart

Typed error handling in Python and TypeScript, reading the 422, walking the catalog.

Limitations

What Router does not do today, and what to use instead.

Get Started

Agent Tools

Basic Concepts

Interface Guide

Tutorials

Partner Nodes

Use FLUX 3 Video with Comfy Router

Quick start

Schema

Input

Output

Examples

Input

Output

Before you ship

Headers

Quickstart

Limitations

​Quick start

​Schema

​Input

​Output

​Examples

​Input

​Output

​Before you ship

Headers

Quickstart

Limitations

Quick start

Schema

Input

Output

Examples

Input

Output

Before you ship