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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/stable-audio-3/medium/audio-outpainting", {
input: {
prompt: "soft strings continue the melody",
audio_url: "https://storage.googleapis.com/falserverless/model_tests/diffrythm/rock_en.wav"
},
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/stable-audio-3/medium/audio-outpainting", {
input: {
prompt: "soft strings continue the melody",
audio_url: "https://storage.googleapis.com/falserverless/model_tests/diffrythm/rock_en.wav"
},
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/stable-audio-3/medium/audio-outpainting", {
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/stable-audio-3/medium/audio-outpainting", {
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.
negative_prompt stringText description of qualities to avoid in the output. Default value: ""
num_inference_steps integerNumber of sampling steps. Post-trained (distilled) checkpoints look good with the default 8 and gain little from going higher. Default value: 8
guidance_scale floatClassifier-free guidance scale. Higher values follow the prompt more strictly. Only effective on base (non-distilled) checkpoints. Default value: 1
seed integerRandom seed for reproducible outputs. Omit for a random seed.
enable_prompt_expansion booleanIf True, the prompt will be expanded using an LLM for more detailed and higher quality results.
enable_safety_checker booleanEnable NSFW content safety checking. Default value: true
sync_mode booleanIf True, the audio is returned inline as a data URI and the result is not saved to the request history.
output_format OutputFormatEnumContainer format for the generated audio output. Default value: "mp3"
Possible enum values: mp3, wav, flac, ogg, opus, m4a, aac
bitrate stringAudio bitrate for compressed output formats (e.g., mp3, aac, opus). Format e.g. '192k' or '320k'. Ignored for lossless formats (wav, flac). Default value: "192k"
prompt string* requiredText description guiding the extension content.
audio_url string* requiredSource audio to extend.
extend_seconds_before floatSeconds of new audio to generate before the source audio.
extend_seconds_after floatSeconds of new audio to generate after the source audio.
{
"num_inference_steps": 8,
"guidance_scale": 1,
"enable_safety_checker": true,
"output_format": "mp3",
"bitrate": "192k",
"prompt": "soft strings continue the melody",
"audio_url": "https://storage.googleapis.com/falserverless/model_tests/diffrythm/rock_en.wav",
"extend_seconds_before": 0,
"extend_seconds_after": 30
}The generated audio clip.
seed integer* requiredThe random seed used for generation.
prompt string* requiredThe prompt used for generation.
{
"audio": {
"url": "",
"content_type": "image/png",
"file_name": "z9RV14K95DvU.png",
"file_size": 4404019
},
"prompt": ""
}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.