Speech
AI text-to-speech — turn text into natural studio-grade audio, pay per clip in USDC or EURC. No API key, no account required.
What is Speech?
Text-to-speech behind x402 micropayments. A single POST /speech/synthesize endpoint accepts up to 4,000 characters of text plus a voice and returns synthesized audio. Powered by the qwen-audio-3.0-tts-plus model (premium speech tier of the Qwen Audio family) with two flagship voices: longanlufeng (male, bright and cheerful) and longanlingxin (female, warm and empathetic), each fluent in Chinese (Mandarin) and English. Output formats: mp3 (default), wav, pcm, opus, with volume, speech-rate and pitch controls. Clips are stored for 2 hours after generation — poll GET /speech/status/{audio_id} (free) and download via GET /speech/audio/{audio_id} (free).
Pay per call in USDC, EURC across Base, Arbitrum, Polygon and Avalanche via the x402 micropayment protocol — no subscriptions, no API keys, no wallets to configure for the caller.
Operations
Show all operations
inference
| Method | Endpoint | Description | Tier |
|---|---|---|---|
POST | /speech/synthesize | Synthesize speech from text on the qwen-audio-3.0-tts-plus model. Billed on the Exclusive tier, per clip. Returns an audio_id immediately; poll /speech/status/{audio_id} then download /speech/audio/{audio_id} (both free). | exclusive |
Workflows
- speech_synthesize — Turn text into audio: POST /speech/synthesize (paid) → poll GET /speech/status/{audio_id} (free) until status is completed → GET /speech/audio/{audio_id} (free) for the clip:
synthesize
Data sources
- Alibaba DashScope API — qwen-audio-3.0-tts-plus via the native SpeechSynthesizer endpoint. Proxied server-side; the service's own API key is never exposed to callers. Upstream audio URLs are short-lived — the service downloads and re-serves the bytes.
Examples
synthesize
Speak a short English announcement with the male flagship voice
{
"text": "Welcome to the x402 speech service.",
"voice": "longanlufeng",
"format": "mp3"
}