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The client provides a convenient way to interact with the model API.
npm install --save @fal-ai/clientThe @fal-ai/serverless-client package has been deprecated in favor of @fal-ai/client. Install the new package and update your imports — see client setup.
Set FAL_KEY as an environment variable in your runtime.
export FAL_KEY="YOUR_API_KEY"The client API handles the API submit protocol. It will handle the request status updates and return the result when the request is completed.
import { fal } from "@fal-ai/client";
const result = await fal.subscribe("fal-ai/scail-2", {
input: {
prompt: "A person dancing gracefully in a sunlit studio",
image_url: "https://v3b.fal.media/files/b/panda/-oMlZo9Yyj_Nzoza_tgds_GmLF86r5bOt50eMMKCszy_eacc949b3933443c9915a83c98fbe85e.png",
video_url: "https://v3b.fal.media/files/b/panda/a6SvJg96V8eoglMlYFShU_5385885-hd_1080_1920_25fps.mp4"
},
logs: true,
onQueueUpdate: (update) => {
if (update.status === "IN_PROGRESS") {
update.logs.map((log) => log.message).forEach(console.log);
}
},
});
console.log(result.data);
console.log(result.requestId);The API uses an API Key for authentication. It is recommended you set the FAL_KEY environment variable in your runtime when possible.
import { fal } from "@fal-ai/client";
fal.config({
credentials: "YOUR_FAL_KEY"
});When running code on the client-side (e.g. in a browser, mobile app or GUI applications), make sure to not expose your FAL_KEY. Instead, use a server-side proxy to make requests to the API. For more information, check out our server-side integration guide.
The client API provides a convenient way to submit requests to the model.
import { fal } from "@fal-ai/client";
const { request_id } = await fal.queue.submit("fal-ai/scail-2", {
input: {
prompt: "A person dancing gracefully in a sunlit studio",
image_url: "https://v3b.fal.media/files/b/panda/-oMlZo9Yyj_Nzoza_tgds_GmLF86r5bOt50eMMKCszy_eacc949b3933443c9915a83c98fbe85e.png",
video_url: "https://v3b.fal.media/files/b/panda/a6SvJg96V8eoglMlYFShU_5385885-hd_1080_1920_25fps.mp4"
},
webhookUrl: "https://optional.webhook.url/for/results",
});You can fetch the status of a request to check if it is completed or still in progress.
import { fal } from "@fal-ai/client";
const status = await fal.queue.status("fal-ai/scail-2", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b",
logs: true,
});Once the request is completed, you can fetch the result. See the Output Schema for the expected result format.
import { fal } from "@fal-ai/client";
const result = await fal.queue.result("fal-ai/scail-2", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b"
});
console.log(result.data);
console.log(result.requestId);Some attributes in the API accept file URLs as input. Whenever that's the case you can pass your own URL or a Base64 data URI.
You can pass a Base64 data URI as a file input. The API will handle the file decoding for you. Keep in mind that for large files, this alternative although convenient can impact the request performance.
You can also pass your own URLs as long as they are publicly accessible. Be aware that some hosts might block cross-site requests, rate-limit, or consider the request as a bot.
We provide a convenient file storage that allows you to upload files and use them in your requests. You can upload files using the client API and use the returned URL in your requests.
import { fal } from "@fal-ai/client";
const file = new File(["Hello, World!"], "hello.txt", { type: "text/plain" });
const url = await fal.storage.upload(file);The client will auto-upload the file for you if you pass a binary object (e.g. File, Data).
Read more about file handling in our file upload guide.
prompt string* requiredThe prompt describing the final video to generate.
image_url string* requiredURL of the reference character image. The character in this image is animated (or used to replace a subject) according to the driving video.
video_url string* requiredURL of the driving (motion) video. The subject can be a human, multiple humans, or an animal.
mode ModeEnumanimation animates the reference character with the driving motion. replacement replaces the driving subject with the reference character while keeping the original scene. Default value: "animation"
Possible enum values: animation, replacement
driving_type DrivingTypeEnumDriving signal for animation mode. end_to_end (default) drives directly from the SAM3-masked driving video and is the recommended, most robust path. pose renders an explicit NLF/DWPose skeleton from the driving video (more control for challenging inputs). Default value: "end_to_end"
Possible enum values: end_to_end, pose
subject_type SubjectTypeEnumType of subject in the driving video. animal switches the SAM3 detection prompt to non-human subjects. Default value: "human"
Possible enum values: human, animal
resolution ResolutionEnumOutput resolution. 512p outputs 896x512 (landscape) or 512x896 (portrait); 704p outputs 1280x704 or 704x1280. Orientation is chosen automatically from the reference image aspect ratio. Default value: "512p"
Possible enum values: 512p, 704p
num_inference_steps integerNumber of diffusion sampling steps. Higher improves quality but is slower. Default value: 40
guidance_scale floatClassifier-free guidance scale. Controls prompt adherence versus creativity. Default value: 5
shift floatFlow-matching noise schedule shift. 3.0 is recommended for the 512p tier. Default value: 3
seed integerRandom seed. Leave empty for a random seed. The seed used is returned in the response.
enable_safety_checker booleanAuthorized callers may set false to request relaxed screening. Default value: true
{
"prompt": "A person dancing gracefully in a sunlit studio",
"image_url": "https://v3b.fal.media/files/b/panda/-oMlZo9Yyj_Nzoza_tgds_GmLF86r5bOt50eMMKCszy_eacc949b3933443c9915a83c98fbe85e.png",
"video_url": "https://v3b.fal.media/files/b/panda/a6SvJg96V8eoglMlYFShU_5385885-hd_1080_1920_25fps.mp4",
"mode": "animation",
"driving_type": "end_to_end",
"subject_type": "human",
"resolution": "512p",
"num_inference_steps": 40,
"guidance_scale": 5,
"shift": 3,
"enable_safety_checker": true
}The generated video file.
seed integer* requiredThe seed used to generate the video.
Debug (only when output_preprocessing=true): the Stage-A pose-conditioning video fed to the diffusion model — the rendered NLF/DWPose skeleton for driving_type=pose, or the SAM3-masked driving video for end_to_end.
Debug (only when output_preprocessing=true): the Stage-A driving mask video.
{
"video": {
"file_size": 1048576,
"content_type": "video/mp4",
"url": "https://storage.googleapis.com/falserverless/example_outputs/scail2-output.mp4",
"file_name": "output.mp4"
}
}url string* requiredThe URL where the file can be downloaded from.
content_type stringThe mime type of the file.
file_name stringThe name of the file. It will be auto-generated if not provided.
file_size integerThe size of the file in bytes.