# Linkrra Pearl Pool Text-to-Speech (TTS)

> Linkrra Pearl Pool Text-to-Speech (TTS) is a paid API for AI agents from pool.linkrra.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-11).

Converts text input to speech audio (WAV) via an OpenAI-compatible API, paid per request in USDC on Base using the x402 payment protocol

## Facts

- Endpoint: POST https://pool.linkrra.com/api/billing/x402/tts?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/linkrra-pearl-pool-text-to-speech-tts-11fbec44
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TUl8A4Em6IS-9evIKzugi

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 linkrra-pearl-pool-text-to-speech-tts-11fbec44 -d '<json body>'
```

Example prompt: Can you convert this text to spoken audio for me: 'Welcome to Linkrra Pearl Pool. Your inference request has been processed.' — I need it as a WAV file.

## When to prefer this

Choose this endpoint when you need OpenAI-compatible TTS with per-request USDC micropayments on Base (x402 protocol), especially in autonomous agent pipelines that handle crypto payments natively. It is well-suited for agents that need flexible, pay-as-you-go voice synthesis without subscription billing, and when integration with the x402 payment standard is already established.

## Known failure modes

- 402 Payment Required — x402 challenge returned if payment header is missing or incorrect; agent must complete USDC payment on Base before retrying
- Invalid input schema — missing required fields (input.type, input.method, input.bodyType, input.body, output.type, output.mimeType) returns a validation error
- Unsupported model or voice — if the requested TTS model is unavailable in the catalogue, request may fail
- Network or inference node unavailability — decentralized GPU pool may have intermittent availability
- Malformed payment — incorrect USDC amount or wrong chain (must be Base, eip155:8453) causes payment rejection

## How this service works

OpenAI-compatible inference paid per request in USDC on Base (eip155:8453, scheme exact). GET /v1/models for the model catalogue and per-model USD prices. Every paid route answers unauthenticated requests with an x402 v2 402 challenge (PAYMENT-REQUIRED header + JSON body). Minimum charge $0.01 per paid call on chat/completions and tts (usage-based price applies above it); credit top-ups are $1 minimum. Contact: weare@linkrra.com

## Output

A binary WAV audio file containing the synthesized speech corresponding to the input text. The response is raw audio bytes with MIME type audio/wav, ready 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/linkrra-pearl-pool-text-to-speech-tts-11fbec44/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pool.linkrra.com](https://www.zero.xyz/host/pool.linkrra.com/llms.txt)