LiveKit Ultravox Plugin
LiveKit plugin for Ultravox's real-time speech-to-speech AI models, providing seamless integration with the LiveKit Agents framework.
Installation
pip install livekit-plugins-ultravox
Prerequisites
You'll need an API key from Ultravox. Set it as an environment variable:
export ULTRAVOX_API_KEY="your_api_key_here"
Optional: enable debug logs for the plugin (disabled by default):
export LK_ULTRAVOX_DEBUG=true
Basic Usage
Simple Voice Assistant
import asyncio
from livekit.agents import Agent, AgentSession, JobContext, WorkerOptions, cli, inference
from livekit.plugins.ultravox.realtime import RealtimeModel
async def entrypoint(ctx: JobContext):
await ctx.connect()
session: AgentSession[None] = AgentSession(
allow_interruptions=True,
vad=inference.VAD(),
llm=RealtimeModel(
model_id="fixie-ai/ultravox",
voice="Mark",
),
)
await session.start(
agent=Agent(
instructions="You are a helpful voice assistant.",
),
room=ctx.room,
)
if __name__ == "__main__":
cli.run_app(WorkerOptions(entrypoint_fnc=entrypoint))
Voice Assistant with Tools
from livekit.agents import function_tool, Agent, AgentSession, JobContext, WorkerOptions, cli, inference
from livekit.plugins.ultravox.realtime import RealtimeModel
@function_tool
async def get_weather(location: str) -> str:
"""Get weather information for a location."""
return f"The weather in {location} is sunny and 72°F"
@function_tool
async def book_appointment(date: str, time: str) -> str:
"""Book an appointment."""
return f"Appointment booked for {date} at {time}"
async def entrypoint(ctx: JobContext):
await ctx.connect()
session: AgentSession[None] = AgentSession(
allow_interruptions=True,
vad=inference.VAD(),
llm=RealtimeModel(model_id="fixie-ai/ultravox"),
)
await session.start(
agent=Agent(
instructions="You are a helpful assistant with access to weather and scheduling tools.",
tools=[get_weather, book_appointment],
),
room=ctx.room,
)
if __name__ == "__main__":
cli.run_app(WorkerOptions(entrypoint_fnc=entrypoint))
Configuration Options
Ultravox API (/api/calls) Parameters
RealtimeModel(
model_id="fixie-ai/ultravox", # Model to use (warn + pass-through if unknown)
voice="Mark", # Voice to use (warn + pass-through if unknown)
api_key=None, # API key (defaults to env var)
base_url=None, # API base URL (defaults to Ultravox API)
system_prompt="You are helpful.", # System prompt
input_sample_rate=16000, # Input audio sample rate
output_sample_rate=24000, # Output audio sample rate
client_buffer_size_ms=60, # Audio buffer size (min 200ms used on WS)
http_session=None, # Custom HTTP session
)
Notes:
- Unknown models/voices: the plugin logs a warning and sends them as-is; the server validates.
- Metrics: the plugin emits a single `metrics_collected` event per generation. To log them,
add a listener in your app and call the helper:
```python
from livekit.agents import metrics
@session.on("metrics_collected")
def on_metrics_collected(ev):
metrics.log_metrics(ev.metrics)
Metadata
Release files for livekit-plugins-ultravox 1.8.5
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| livekit_plugins_ultravox-1.8.5.tar.gz | 19.9 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| livekit_plugins_ultravox-1.8.5-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 41.5 kB
Release files / livekit_plugins_ultravox-1.8.5.tar.gz
| Download URL | livekit_plugins_ultravox-1.8.5.tar.gz |
|---|---|
| Size | 19.9 kB |
| Tags | Source |
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| Download URL | livekit_plugins_ultravox-1.8.5-py3-none-any.whl |
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| Size | 21.6 kB |
| Tags | Python 3 |
|
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| Uploaded via |
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