{"uid":"cap_X0dvwvQDklVzM3BVzO-Yf","slug":"telnyx-x402-text-to-speech-audio-speech-3268bac4","name":"Telnyx x402 Text-to-Speech (Audio/Speech)","description":"Pay USDC per request for Telnyx Inference and Audio (text-to-speech, speech-to-text) through x402.","url":"https://x402.telnyx.com/v1/audio/speech?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"input":{"type":"string","maxLength":3000,"minLength":1,"description":"Text to synthesize (max 3000 characters)."},"model":{"type":"string","description":"Accepted for OpenAI SDK compatibility; the voice id selects the engine."},"voice":{"type":"string","description":"OpenAI voice name (alloy, echo, fable, onyx, nova, shimmer, …) or Telnyx voice id (Provider.Model.VoiceId). Full catalog: GET /v1/audio/voices."},"response_format":{"enum":["mp3"],"type":"string"}}},"responseSchema":{"type":"json","example":"<binary audio/mpeg bytes>"},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.018","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.018/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.018","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.018","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ZKg3lsKKnKHa9I4KzxaoP","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.018","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Converts input text into spoken audio (MP3) using Telnyx's TTS engine, billed per-request at $0.018 USDC via x402 micropayment protocol.","exampleAgentPrompt":"Can you read aloud this text using the 'nova' voice and give me an MP3: 'Welcome to our platform. We're glad you're here. Let's get started together.'","exampleUseCases":[{"title":"Podcast intro narration","prompt":"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.'"},{"title":"Accessibility audio for article","prompt":"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.'"},{"title":"Automated IVR prompt recording","prompt":"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.'"}],"resultDescription":"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.","failureModes":["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"],"whenToPreferThis":"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.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-12T15:32:12.729Z","isFirstParty":false,"canonicalSlug":"telnyx-x402-text-to-speech-audio-speech-3268bac4"}