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Telnyx x402 Text-to-Speech (Audio/Speech)
x402
Telnyx x402 Text-to-Speech (Audio/Speech) is a paid API for AI agents from x402.telnyx.com, paid per call via x402, $0.018/call, status unknown (last checked 2026-10-12).
Converts input text into spoken audio (MP3) using Telnyx's TTS engine, billed per-request at $0.018 USDC via x402 micropayment protocol.
Price / call$0.018
Success—
StatusUnknown
How this service works
Pay USDC per request for Telnyx Inference and Audio (text-to-speech, speech-to-text) through x402.
Output
Returns raw binary audio bytes in MP3 format (audio/mpeg) containing the synthesized speech for the provided text input. The response is a binary stream, not a JSON envelope.
Example use cases
Podcast intro narration
“Turn this script into spoken audio using the 'alloy' voice and give me an MP3 I can drop into my podcast intro: 'Welcome back to The Daily Briefing. Today we're covering the top stories in tech and business.'”
Accessibility audio for article
“I need an audio version of this article paragraph read in the 'shimmer' voice: 'Scientists have discovered a new exoplanet that may support liquid water, raising hopes for extraterrestrial life within our galaxy.'”
Automated IVR prompt recording
“Generate an MP3 of this phone menu prompt using the 'onyx' voice: 'Thank you for calling Acme Support. Press 1 for billing, press 2 for technical issues, or stay on the line for an agent.'”
Technical details
Endpoint
POSThttps://x402.telnyx.com/v1/audio/speech?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need OpenAI-compatible TTS voice names (alloy, echo, fable, onyx, nova, shimmer) but want to pay per-request with USDC via the x402 micropayment protocol without managing a traditional API subscription. It is ideal for agents or workflows that need frictionless, crypto-native billing and want to leverage Telnyx's voice infrastructure. Prefer this over standard Telnyx REST API when operating in a crypto-payment context or building x402-native agent pipelines.
Side effects
- Text input exceeds 3000 character limit — request rejected
- Invalid or unsupported voice ID — may return an error or fall back to default
- Payment failure via x402 protocol — request not fulfilled if USDC payment is rejected
- Empty text input — validation error returned
- Unsupported response_format value — only 'mp3' is accepted
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| input | string | Text to synthesize (max 3000 characters). |
| model | string | Accepted for OpenAI SDK compatibility; the voice id selects the engine. |
| voice | string | OpenAI voice name (alloy, echo, fable, onyx, nova, shimmer, …) or Telnyx voice id (Provider.Model.VoiceId). Full catalog: GET /v1/audio/voices. |
| response_format | string |
Output
Schema · Response
{
"type": "json",
"example": "<binary audio/mpeg bytes>"
}Tags
x402
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