Text to Speech/Create Speech

Create Speech

POST/api/v1/tts

Convert text to speech with VisionStory smart TTS. Pick a voice from GET /api/v1/voices (public or your cloned voices). The service automatically selects the best synthesis strategy for the voice and the text language. Billing: 2 credits per 1000 characters (rounded up), only charged on success.

Synchronous — the response body is the MP3 audio itself (audio/mpeg). Duration and billing are returned in the X-Audio-Duration-Sec, X-Usage-Characters and X-Cost-Credit headers. The audio is not stored on our side, so save the response body; a repeat call regenerates and bills again. Per-key concurrency is limited during beta; requests beyond the limit are rejected, not queued.

Headers

X-API-KeystringRequired

Your VisionStory API key (sk-vs-...), kept server-side. Create one at OpenApi (Pro plan and up).

Request body

textstringRequired

Text to synthesize, up to 3000 characters

voice_idstringRequired

Public or cloned voice id, check GET /api/v1/voices

Response

200Successful Response

Successful calls return a standard envelope: the endpoint payload under data (its fields are documented below), plus a message string ("success") and an ISO 8601 server_time.

Errors

All error responses share one JSON envelope: an error object with a numeric code, a human-readable message, an optional details string, and an optional hint giving an actionable next step (handy for AI agents).

errorErrorDetailRequired

Error payload returned with every non-2xx response. Present only on failure; successful calls use the standard success envelope instead.

Show 4 propertiesHide 4 properties

codeintegerRequired

Machine-readable error code. Mirrors the HTTP status for transport-level failures (e.g. 401, 404, 422, 500) and may carry a business-specific code otherwise.

messagestringRequired

Human-readable explanation of what went wrong. Safe to log or surface to end users; not localized.

detailsstring | nullOptional

Optional structured detail about the failure, e.g. a JSON string of per-field validation errors on a 422. Absent when there is nothing extra to report.

hintstring | nullOptional

Actionable next step for resolving the error, written for both humans and AI agents (e.g. how to fix the request, or where to obtain an API key). May be absent.

Request

curl -X POST 'https://openapi.visionstory.ai/api/v1/tts' \
  -H 'X-API-Key: sk-vs-xxxxxxxxxxxxxxxxxxx' \
  -H 'Content-Type: application/json' \
  -d '{
  "text": "string",
  "voice_id": "Alice"
}'

import requests

url = "https://openapi.visionstory.ai/api/v1/tts"
headers = {
    "X-API-Key": "sk-vs-xxxxxxxxxxxxxxxxxxx",
    "Content-Type": "application/json",
}
payload = {
  "text": "string",
  "voice_id": "Alice"
}
response = requests.post(url, headers=headers, json=payload)
print(response.json())

const response = await fetch("https://openapi.visionstory.ai/api/v1/tts", {
  method: "POST",
  headers: {
    "X-API-Key": "sk-vs-xxxxxxxxxxxxxxxxxxx",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "text": "string",
    "voice_id": "Alice"
  }),
});
const data = await response.json();
console.log(data);

package main

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

func main() {
	payload := []byte(`{
  "text": "string",
  "voice_id": "Alice"
}`)
	req, _ := http.NewRequest("POST", "https://openapi.visionstory.ai/api/v1/tts", bytes.NewBuffer(payload))
	req.Header.Set("X-API-Key", "sk-vs-xxxxxxxxxxxxxxxxxxx")
	req.Header.Set("Content-Type", "application/json")
	resp, _ := http.DefaultClient.Do(req)
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	fmt.Println(string(body))
}

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://openapi.visionstory.ai/api/v1/tts"))
    .header("X-API-Key", "sk-vs-xxxxxxxxxxxxxxxxxxx")
    .header("Content-Type", "application/json")
    .method("POST", HttpRequest.BodyPublishers.ofString("""
        {
          "text": "string",
          "voice_id": "Alice"
        }"""))
    .build();
HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
System.out.println(response.body());

<?php
$ch = curl_init("https://openapi.visionstory.ai/api/v1/tts");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "X-API-Key: sk-vs-xxxxxxxxxxxxxxxxxxx",
    "Content-Type: application/json",
]);
$payload = <<<'JSON'
{
  "text": "string",
  "voice_id": "Alice"
}
JSON;
curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

require "net/http"
require "uri"

uri = URI("https://openapi.visionstory.ai/api/v1/tts")
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true
request = Net::HTTP::Post.new(uri)
request["X-API-Key"] = "sk-vs-xxxxxxxxxxxxxxxxxxx"
request["Content-Type"] = "application/json"
request.body = <<~JSON
  {
    "text": "string",
    "voice_id": "Alice"
  }
  JSON
response = http.request(request)
puts response.body

import Foundation

var request = URLRequest(url: URL(string: "https://openapi.visionstory.ai/api/v1/tts")!)
request.httpMethod = "POST"
request.setValue("sk-vs-xxxxxxxxxxxxxxxxxxx", forHTTPHeaderField: "X-API-Key")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
request.httpBody = """
{
  "text": "string",
  "voice_id": "Alice"
}
""".data(using: .utf8)
let (data, _) = try await URLSession.shared.data(for: request)
print(String(data: data, encoding: .utf8) ?? "")

using System;
using System.Net.Http;
using System.Text;

var client = new HttpClient();
var request = new HttpRequestMessage(HttpMethod.Post, "https://openapi.visionstory.ai/api/v1/tts");
request.Headers.Add("X-API-Key", "sk-vs-xxxxxxxxxxxxxxxxxxx");
var payload = """
{
  "text": "string",
  "voice_id": "Alice"
}
""";
request.Content = new StringContent(payload, Encoding.UTF8, "application/json");
var response = await client.SendAsync(request);
Console.WriteLine(await response.Content.ReadAsStringAsync());