# ForgeMesh TTS Base-Long (Text-to-Speech, 501–2000 chars)

> ForgeMesh TTS Base-Long (Text-to-Speech, 501–2000 chars) is a paid API for AI agents from tts.forgemesh.io, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Converts long-form text (up to 2000 characters) into 44.1kHz 16-bit mono WAV audio in 31 languages using a selectable male or female voice, paid per-call via x402 with no API key required.

## Facts

- Endpoint: POST https://tts.forgemesh.io/v1/tts/base-long
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/forgemesh-tts-base-long-text-to-speech-501-2000-chars-36d240ef
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qw4VAfL4X7ZHEtq2YUyvB

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-tts-base-long-text-to-speech-501-2000-chars-36d240ef -d '<json body>'
```

Example prompt: Read this 3-paragraph blog introduction aloud in English using a female voice (F2): 'Welcome to our quarterly review. This year has seen remarkable growth across all divisions. We look forward to sharing detailed results with you today.'

## When to prefer this

Choose this endpoint when you need to synthesize longer text passages (501–2000 characters) into high-quality WAV audio without managing API keys or subscription accounts. It is ideal for agents that need multilingual voice output across 31 languages with selectable voice gender and style, and can handle micropayments via x402. Prefer the non-long sibling routes for shorter texts (1–500 chars) to avoid unnecessary cost. Prefer this over ElevenLabs or Google TTS when you need a key-free, pay-per-call model compatible with x402 payment flows.

## Known failure modes

- Text under 1 character or over 2000 characters returns a validation error (use non-long routes for texts under 501 chars)
- Unsupported language code returns an enum validation error
- Invalid voice ID (outside M1-M5, F1-F5) returns a validation error
- Payment failure via x402 (insufficient USDC balance) results in a 402 Payment Required response
- Network timeout if synthesis takes longer than the server deadline

## How this service works

Paid text-to-speech via x402. WAV audio in 31 languages, OpenAI-compatible, no API keys.

## Output

Returns a 44.1kHz 16-bit mono WAV audio file inline (Content-Type: audio/wav) containing the synthesized speech of the submitted text. The audio is ready for direct playback or embedding without additional decoding.

## 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."
  },
  "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-tts-base-long-text-to-speech-501-2000-chars-36d240ef/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from tts.forgemesh.io](https://www.zero.xyz/host/tts.forgemesh.io/llms.txt)