# Venice TTS Voice Synthesis

> Venice TTS Voice Synthesis is a paid API for AI agents from x402-deployer.x402-deployer.workers.dev, paid per call via x402, $0.05/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 speech audio using multiple TTS providers (Kokoro, ElevenLabs, Orpheus, MiniMax) with 30+ voices and multiple output formats.

## Facts

- Endpoint: POST https://x402-deployer.x402-deployer.workers.dev/voice?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-09
- Last successful call: 2026-06-30
- Success rate: 33% of calls made through Zero
- Rating: 4.3 / 5 from 1 review
- Activations on Zero: 4
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-deployer-x402-deployer-workers-dev-fc4ca503
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Mfi_BC2wRN7ulT6u6-I0g

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 x402-deployer-x402-deployer-workers-dev-fc4ca503 -d '<json body>'
```

Example prompt: Can you read this aloud for me using a warm female voice and give me an MP3: 'Welcome to our weekly newsletter. This week we cover the latest breakthroughs in renewable energy.'

## When to prefer this

Choose this endpoint when you need high-quality TTS with broad voice selection (30+ voices) and multiple providers including Kokoro, ElevenLabs, Orpheus, and MiniMax, and you want flexible audio output formats. Ideal for AI agents building audio content, narrating articles, or producing voice responses.

## Known failure modes

- Unsupported voice name returns an error or falls back to default
- Invalid output format returns a 400 error
- Text too long may be truncated or rejected
- Provider-specific outages may cause synthesis failure
- Missing payment header results in 402 Payment Required

## How this service works

Text-to-speech / TTS / voice synthesis. Venice TTS (Kokoro/xAI/ElevenLabs/Orpheus/MiniMax). 30+ voices, MP3/WAV/OPUS/AAC/FLAC.

## Output

Returns a synthesized audio file in the requested format (MP3, WAV, OPUS, AAC, or FLAC) containing the spoken version of the input text, rendered by the selected voice and TTS provider.

## Example request

```json
{
 "input": {
  "body": {
   "text": "Welcome to our weekly newsletter. This week we cover the latest breakthroughs in renewable energy.",
   "model": "tts-kokoro",
   "speed": 1,
   "voice": "af_bella",
   "format": "mp3"
  },
  "type": "http",
  "method": "POST",
  "bodyType": "json"
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [
      "text"
     ],
     "properties": {
      "text": {
       "type": "string",
       "description": "Text to synthesize into speech. Max 4000 chars."
      },
      "model": {
       "type": "string",
       "description": "TTS model id. Optional, default 'tts-kokoro'."
      },
      "speed": {
       "type": "number",
       "description": "Playback speed multiplier. Optional, 0.25-4, default 1."
      },
      "voice": {
       "type": "string",
       "description": "Voice id, e.g. 'af_sky'. Optional, default 'af_sky'."
      },
      "format": {
       "type": "string",
       "description": "Output audio format: mp3, wav, opus, aac, or flac. Optional, default mp3."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "audio_url": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-deployer-x402-deployer-workers-dev-fc4ca503/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-deployer.x402-deployer.workers.dev](https://www.zero.xyz/host/x402-deployer.x402-deployer.workers.dev/llms.txt)