# Synap TTS — Text-to-Speech via x402

> Synap TTS — Text-to-Speech via x402 is a paid API for AI agents from synap.linkrra.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-23).

Converts text input to speech audio, returning a WAV file, billed per-call via x402 micropayment at $0.01 USDC.

## Facts

- Endpoint: POST https://synap.linkrra.com/api/billing/x402/tts?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synap-tts-text-to-speech-via-x402-cdf38635
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_7KG2bHmilPeSbVDhX1aVB

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 synap-tts-text-to-speech-via-x402-cdf38635 -d '<json body>'
```

Example prompt: Say this out loud for me and give me a WAV file: 'Welcome to our platform. Your account has been successfully created.' — use Synap's TTS to synthesize it.

## When to prefer this

Choose this endpoint when you need per-call micropayment TTS with no subscription, no data retention, and OpenAI-compatible semantics — particularly useful in privacy-sensitive contexts or pay-as-you-go agent workflows using the x402 payment protocol. Prefer over larger TTS providers when minimizing cost per call ($0.01 USDC) and avoiding data storage are priorities.

## Known failure modes

- Missing required fields (input.type, input.method, input.bodyType, input.body, output.type, output.mimeType) — returns 400 validation error
- Insufficient USDC balance or x402 payment failure — returns 402 Payment Required
- Unsupported output MIME type specified — may return 400 or 415
- Empty or malformed text body — may return empty audio or 400 error
- Service unavailability due to community GPU resource constraints — returns 503 or timeout

## How this service works

AI powered by the people, for the people. OpenAI-compatible inference API with zero data retention — qwen3-coder-30b at $0.0675/1M in, $0.27/1M out. Contribute your GPU, earn credits.

## Output

A binary WAV audio file (audio/wav) containing the synthesized speech corresponding to the submitted text input. The response is raw audio bytes suitable for playback or storage.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string"
    },
    "method": {
     "type": "string"
    },
    "bodyType": {
     "type": "string"
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type",
    "mimeType"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "mimeType": {
     "type": "string"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "binary",
 "example": "<WAV file bytes>",
 "mimeType": "audio/wav"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synap-tts-text-to-speech-via-x402-cdf38635/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synap.linkrra.com](https://www.zero.xyz/host/synap.linkrra.com/llms.txt)