Cartesia

Tools for interacting with Cartesia Voice AI services including text-to-speech and voice localization

CartesiaTools enable an Agent to perform text-to-speech, list available voices, and localize voices using Cartesia.

Prerequisites

The following example requires the cartesia library and an API key.

uv pip install cartesia

export CARTESIA_API_KEY="your_api_key_here"

Example

from agno.agent import Agent
from agno.tools.cartesia import CartesiaTools
from agno.utils.audio import write_audio_to_file

# Initialize Agent with Cartesia tools
agent = Agent(
    name="Cartesia TTS Agent",
    description="An agent that uses Cartesia for text-to-speech.",
    tools=[CartesiaTools()],
)

response = agent.run(
    """Generate a simple greeting using Text-to-Speech:

    Say "Welcome to Cartesia, the advanced  speech synthesis platform. This speech is generated by an agent."
    """
)

# Save the generated audio
if response.audio:
    write_audio_to_file(audio=response.audio[0].content, filename="tmp/greeting.mp3")

Advanced Example: Translation and Voice Localization

This example demonstrates how to translate text, analyze emotion, localize a new voice, and generate a voice note using CartesiaTools.

from textwrap import dedent
from agno.agent import Agent
from agno.models.openai import OpenAIResponses
from agno.tools.cartesia import CartesiaTools
from agno.utils.audio import write_audio_to_file

agent_instructions = dedent(
    """Follow these steps SEQUENTIALLY to translate text and generate a localized voice note:
    1. Identify the text to translate and the target language from the user request.
    2. Translate the text accurately to the target language.
    3. Analyze the emotion conveyed by the translated text.
    4. Call `list_voices` to retrieve available voices.
    5. Select a base voice matching the language and emotion.
    6. Call `localize_voice` to create a new localized voice.
    7. Call `text_to_speech` to generate the final audio.
    """
)

agent = Agent(
    name="Emotion-Aware Translator Agent",
    description="Translates text, analyzes emotion, selects a suitable voice, creates a localized voice, and generates a voice note (audio file) using Cartesia TTS tools.",
    instructions=agent_instructions,
    model=OpenAIResponses(id="gpt-5.2"),
    tools=[CartesiaTools(enable_localize_voice=True)],  
    )

agent.print_response(
    "Translate 'Hello! How are you? Tell me more about the weather in Paris?' to French and create a voice note."
)
response = agent.run_response

if response.audio:
    write_audio_to_file(
        response.audio[0].base64_audio,
        filename="french_weather.mp3",
    )

Toolkit Params

Parameter	Type	Default	Description
api_key	str	None	The Cartesia API key for authentication. If not provided, uses the CARTESIA_API_KEY env variable.
model_id	str	sonic-2	The model ID to use for text-to-speech.
default_voice_id	str	78ab82d5-25be-4f7d-82b3-7ad64e5b85b2	The default voice ID to use for text-to-speech and localization.
enable_text_to_speech	bool	True	Enable text-to-speech functionality.
enable_list_voices	bool	True	Enable listing available voices functionality.
enable_localize_voice	bool	False	Enable voice localization functionality.

Toolkit Functions

Function	Description
list_voices	List available voices from Cartesia.
text_to_speech	Converts text to speech.
localize_voice	Create a new localized voice.

Developer Resources

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