Speechify plugin for LiveKit Agents

Speechify text-to-speech for LiveKit Agents. Built on the official speechify-api SDK.

Streaming with word-level timestamps: stream() splits input into sentences and issues one /audio/speech request per sentence, emitting audio and aligned word timestamps as each sentence completes — near-streaming time-to-first-audio plus word marks (streaming and aligned_transcript capabilities).

Installation

pip install speechify-livekit

Authentication

Set your Speechify API key via the environment:

export SPEECHIFY_API_KEY="your-api-key"

Or pass it directly with api_key=....

Usage

from livekit.agents import AgentSession
from livekit.plugins import speechify

session = AgentSession(
    tts=speechify.TTS(
        voice_id="jack",
        model="simba-english",
    ),
)

Options

Option	Default	Description
voice_id	"jack"	Voice to synthesize with (see the Speechify /v1/voices endpoint).
model	provider default	simba-english, simba-multilingual, or simba-3.0.
language	provider default	BCP-47 code of the input, e.g. en-US.
loudness_normalization	provider default	Normalize output loudness.
text_normalization	provider default	Expand numbers/dates into words before synthesis.
tokenizer	basic sentence tokenizer	Sentence tokenizer used to chunk input in stream().
api_key	$SPEECHIFY_API_KEY	Speechify API key.
base_url	SDK default	Override the API base URL.
client	—	Pass a preconfigured speechify.AsyncSpeechify client.

Audio is raw 16-bit little-endian PCM at 24 kHz mono. simba-3.0 is recommended for the lowest time-to-first-audio.