curl --request POST \
  --url https://api.cartesia.ai/files \
  --header 'Authorization: Bearer <token>' \
  --header 'Cartesia-Version: <cartesia-version>' \
  --header 'Content-Type: multipart/form-data' \
  --form file='@example-file' \
  --form purpose=agent_background_sound

import requests

url = "https://api.cartesia.ai/files"

files = { "file": ("example-file", open("example-file", "rb")) }
payload = { "purpose": "agent_background_sound" }
headers = {
    "Cartesia-Version": "<cartesia-version>",
    "Authorization": "Bearer <token>"
}

response = requests.post(url, data=payload, files=files, headers=headers)

print(response.text)

const form = new FormData();
form.append('file', '<string>');
form.append('purpose', 'agent_background_sound');

const options = {
  method: 'POST',
  headers: {'Cartesia-Version': '<cartesia-version>', Authorization: 'Bearer <token>'}
};

options.body = form;

fetch('https://api.cartesia.ai/files', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.cartesia.ai/files",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"purpose\"\r\n\r\nagent_background_sound\r\n-----011000010111000001101001--",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Cartesia-Version: <cartesia-version>",
    "Content-Type: multipart/form-data"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.cartesia.ai/files"

	payload := strings.NewReader("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"purpose\"\r\n\r\nagent_background_sound\r\n-----011000010111000001101001--")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Cartesia-Version", "<cartesia-version>")
	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.cartesia.ai/files")
  .header("Cartesia-Version", "<cartesia-version>")
  .header("Authorization", "Bearer <token>")
  .body("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"purpose\"\r\n\r\nagent_background_sound\r\n-----011000010111000001101001--")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.cartesia.ai/files")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Cartesia-Version"] = '<cartesia-version>'
request["Authorization"] = 'Bearer <token>'
request.body = "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"purpose\"\r\n\r\nagent_background_sound\r\n-----011000010111000001101001--"

response = http.request(request)
puts response.read_body

{
  "id": "file_EneDabCuJCpfe5CFi5X12e",
  "filename": "background-sound.wav",
  "purpose": "agent_background_sound",
  "size": 2048576,
  "status": "ready",
  "owner_id": "org_2x6zg1zx5cnZJHwZCJypdW6YIiC",
  "created_at": "2026-07-25T18:30:00.000Z"
}