# ForgeMesh Voice Pro TTS

> ForgeMesh Voice Pro TTS is a paid API for AI agents from voice.forgemesh.io, paid per call via x402, $0.003/call, not verified (last probed 2026-10-09); live alternatives: x402engine ElevenLabs Text-to-Speech ($0.02) and Google Gemini 3.1 Flash TTS ($0.0028).

Agents call it through Zero, which pays per call: no API key and no wallet of your own. New accounts start with $5.

Live alternatives for the same use case:
- [x402engine ElevenLabs Text-to-Speech](https://www.zero.xyz/c/x402engine-elevenlabs-text-to-speech-6db68b62) ($0.02)
- [Google Gemini 3.1 Flash TTS](https://www.zero.xyz/c/audio-withzero-xyz-google-gemini-3-1-flash-tts-text-to-speech-f794324b) ($0.0028)

Converts text to high-quality speech audio using persona voices across 31 languages with configurable speed and diffusion steps, returning a WAV file.

## Facts

- Endpoint: POST https://voice.forgemesh.io/v1/tts/pro?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-09
- Last successful call: 2026-07-02
- Success rate: 100% of calls made through Zero
- Rating: 3.3 / 5 from 1 review
- Activations on Zero: 2
- Tags: x402
- Canonical page: https://www.zero.xyz/c/forgemesh-voice-pro-tts-ab919a97
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6pSWWT0QONT_V57YTg8nl

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability forgemesh-voice-pro-tts-ab919a97 -d '<json body>'
```

Example prompt: Read this passage aloud in French using the Storyteller persona at 1.3x speed with 20 diffusion steps: 'Il était une fois, dans un royaume lointain, un jeune prince qui rêvait de voir le monde.'

## When to prefer this

Choose this endpoint when you need a pay-per-call TTS API with no subscription, support for 31 languages, named persona voices (Storyteller, Narrator, etc.), and fine-grained diffusion quality control. Ideal for AI agents, automated pipelines, or creators who want per-invocation USDC billing via x402 rather than a monthly SaaS plan.

## Known failure modes

- Text exceeds 2000 character limit — request rejected
- Unsupported language code provided — error returned
- Invalid voice identifier (not in M1-M5, F1-F5, or persona list) — error
- Speed out of range (outside 0.7-2.0) — validation error
- Steps out of range (outside 1-100) — validation error
- Payment failure via x402 — 402 Payment Required response
- Service unavailability — 5xx error

## How this service works

Text-to-speech with speed (0.7x-2.0x) and quality-step (1-100) control, 1 of 10 standard voices across 31 languages, up to 500 characters, returned as WAV audio. Use it to: speak an urgent alert faster, slow a reading for clarity, tune synthesis quality against latency, produce a paced voice cue for a UI, generate a rushed or calm-toned notification. USDC on Base via x402, no API key.

## Output

A 44.1kHz 16-bit mono WAV audio file containing the synthesized speech of the provided text, in the requested language and voice persona.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "lang": {
   "enum": [
    "en",
    "ko",
    "ja",
    "ar",
    "bg",
    "cs",
    "da",
    "de",
    "el",
    "es",
    "et",
    "fi",
    "fr",
    "hi",
    "hr",
    "hu",
    "id",
    "it",
    "lt",
    "lv",
    "nl",
    "pl",
    "pt",
    "ro",
    "ru",
    "sk",
    "sl",
    "sv",
    "tr",
    "uk",
    "vi"
   ],
   "type": "string",
   "description": "Language code; 31 languages supported"
  },
  "text": {
   "type": "string",
   "maxLength": 2000,
   "minLength": 1,
   "description": "Text to synthesize into speech, max 2000 characters. Use non-long routes for 1-500 chars and -long routes for 501-2000 chars."
  },
  "speed": {
   "type": "number",
   "maximum": 2,
   "minimum": 0.7,
   "description": "Pro/Custom expressive speed control, 0.7-2.0. Presets: slow 0.7, normal 1.0, fast 1.3, rapid 1.6"
  },
  "steps": {
   "type": "integer",
   "maximum": 100,
   "minimum": 1,
   "description": "Pro/Custom quality control, 1-100. Presets: draft 4, standard 8, high 16, ultra 24"
  },
  "voice": {
   "enum": [
    "M1",
    "M2",
    "M3",
    "M4",
    "M5",
    "F1",
    "F2",
    "F3",
    "F4",
    "F5"
   ],
   "type": "string",
   "description": "Standard voice: M1-M5 or F1-F5"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "description": "44.1kHz 16-bit mono WAV speech audio returned inline",
  "content_type": "audio/wav"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/forgemesh-voice-pro-tts-ab919a97/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from voice.forgemesh.io](https://www.zero.xyz/host/voice.forgemesh.io/llms.txt)