fal/h3-max, served by Comfy Router from fal.
Quick start
Create a key at platform.comfy.org/profile/api-keys and export it asCOMFY_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: fal/h3-max
Endpoint: POST https://api.comfy.org/v2/models/fal/h3-max
Schema
Input
string
default:"\"16:9\""
Aspect ratio: 21:9, 16:9, 4:3, 1:1, 3:4, or 9:16.
integer
default:"5"
Duration of the generated video in seconds.
boolean
default:"true"
Enable the safety checker.
string
required
Text prompt for video generation.
string
required
How much effort to spend rewriting the prompt before generation: balanced or quality.
string
default:"\"768P\""
Resolution of the generated video: 480P or 768P.
integer
Random seed. A random seed is selected when omitted.
boolean
Return the generated video as base64 instead of a CDN URL.
GET /v2/models/fal/h3-max/openapi.json, the same document it validates a call against before the request reaches the provider.
Output
Router does not publish an output schema for this model.Examples
Input
Before you ship
The SDKs create anIdempotency-Key and reuse it for automatic retries. For manual retries, reuse the original key. Router can hold the connection for up to 10 minutes.
When a request fails, Router sends an X-Comfy-Error-Type response header explaining why. A 422 means Router rejected the input before calling the provider. Download generated assets promptly because result URLs can expire.
Headers
Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.
Using the Router API
Model discovery, validation errors, retries, and billing.
Limitations
What Router does not do today, and what to use instead.