Cartesia

Cartesia is a speech-to-text plugin. It transcribes the caller’s audio into text for the LLM over Cartesia’s streaming WebSocket API, using the ink-whisper model.

Cartesia is also available as a text-to-speech plugin.

Setup

Set your Cartesia API key in the worker environment. Generate a key from the Cartesia dashboard:

export CARTESIA_API_KEY=<key>

Usage

Import the plugin and pass it to the pipeline’s stt slot.

from zrt.plugins import CartesiaSTT

stt = CartesiaSTT(
    model="ink-whisper",
    language="en",
)

# Pipeline(stt=stt, ...)

Parameters

Constructor parameters for the Python SDK (CartesiaSTT).

Parameter	Type	Default	Description
`api_key`	`str`	`None`	Cartesia API key. Falls back to the `CARTESIA_API_KEY` environment variable when unset.
`model`	`str`	`"ink-whisper"`	Cartesia speech-to-text model.
`language`	`str`	`"en"`	Expected language of the caller’s speech.
`input_sample_rate`	`int`	`48000`	Sample rate (Hz) of the incoming PCM audio; must match the capture rate.
`output_sample_rate`	`int`	`16000`	Sample rate (Hz) at which Cartesia processes audio internally.
`base_url`	`str`	`None`	Override the Cartesia WebSocket base URL. Defaults to `None` (uses `wss://api.cartesia.ai`).

Import paths

SDK	Import	Constructor
Python	`from zrt.plugins import CartesiaSTT`	`CartesiaSTT(...)`
JavaScript	-	Coming soon
Go	-	Coming soon

Transcribed text passes to the LLM once turn detection decides the caller has finished speaking.

OpenAI Gladia

Plugins

Inference Gateway

Speech-to-text

LLM

Text-to-speech

Realtime models

Avatars

Turn detection

Voice activity detection

Noise cancellation

Setup

Usage

Parameters

Import paths

​Setup

​Usage

​Parameters

​Import paths

Setup

Usage

Parameters

Import paths