AWS Polly

AWS Polly TTS provider — neural, generative, and long-form synthesis engines.

Voice format: aws.Polly.<Engine>.<VoiceId>

Example: aws.Polly.Generative.Lucia

The engine can also be parsed from a hyphenated suffix on the voice ID — e.g., Lucia-longform resolves to engine long-form.

Voice Samples

Voice	Language	Gender	Sample
aws.Polly.Danielle-Neural	en-US	Female
aws.Polly.Gregory-Neural	en-US	Male
aws.Polly.Lucia-Generative	es-ES	Female

---

WebSocket

Query Parameters

Parameter	Type	Default	Description
audio_format	string	mp3	mp3, linear16, ogg_vorbis.
sample_rate	integer	—	8000, 16000, 22050, 24000.
language	string	—	BCP-47 language code. Passed as language_code to Polly.
text_type	string	text	text or ssml. Polly supports SSML for fine-grained prosody control.

Voice Settings

Field	Type	Default	Description
engine	string	standard	standard, neural, generative, long-form.
output_format	string	—	Any Polly output format.
sample_rate	string	—	e.g. "8000", "16000", "22050", "24000". Valid values depend on engine and format.
lexicon_names	array	—	Pronunciation lexicon names to apply.
language_code	string	—	BCP-47. Overrides language query param.
text_type	string	text	text or ssml. Overrides query param.

{
  "text": " ",
  "voice_settings": {
    "engine": "generative",
    "output_format": "mp3",
    "sample_rate": "24000"
  }
}

REST API

Fields

Field	Type	Default	Description
engine	string	standard	standard, neural, generative, long-form.
output_format	string	—	Polly output format.
sample_rate	string	—	Sample rate in Hz.
lexicon_names	array	—	Pronunciation lexicon names.
language_code	string	—	BCP-47 language code.
text_type	string	text	text or ssml.
output_type	string	binary_output	binary_output, base64_output, or audio_id.

Response

Default (binary_output): chunked audio bytes. Format depends on output_format.

With output_type: "base64_output": JSON with base64-encoded audio.

With output_type: "audio_id": JSON with an audio_url for deferred retrieval.