├── .gitignore ├── inbound-trunk.json ├── requirements.txt ├── dispatch-rule.json ├── .env.example ├── agent.py ├── README.md └── LICENSE /.gitignore: -------------------------------------------------------------------------------- 1 | .env.local 2 | myenv/ 3 | .DS_Store 4 | -------------------------------------------------------------------------------- /inbound-trunk.json: -------------------------------------------------------------------------------- 1 | { 2 | "trunk": { 3 | "name": "LiveKit-NextJS-Twilio-Trunk", 4 | "allowed_addresses": [ 5 | "54.172.60.0/30", 6 | "54.244.51.0/30" 7 | ], 8 | "krisp_enabled": true 9 | } 10 | } -------------------------------------------------------------------------------- /requirements.txt: -------------------------------------------------------------------------------- 1 | livekit-agents>=0.12.11 2 | livekit-plugins-openai>=0.10.17 3 | livekit-plugins-deepgram>=0.6.17 4 | livekit-plugins-elevenlabs>=0.7.11 5 | livekit-plugins-silero>=0.7.4 6 | livekit-plugins-turn-detector>=0.4.0 7 | python-dotenv~=1.0 8 | aiohttp>=3.11.11 9 | -------------------------------------------------------------------------------- /dispatch-rule.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "LiveKit-NextJS-Twilio-Dispatch", 3 | "rule": { 4 | "dispatchRuleIndividual": { 5 | "roomPrefix": "call" 6 | } 7 | }, 8 | "room_config": { 9 | "agents": [ 10 | { 11 | "agent_name": "inbound-agent" 12 | } 13 | ] 14 | } 15 | } -------------------------------------------------------------------------------- /.env.example: -------------------------------------------------------------------------------- 1 | LIVEKIT_URL= 2 | LIVEKIT_API_KEY= 3 | LIVEKIT_API_SECRET= 4 | OPENAI_API_KEY= 5 | DEEPGRAM_API_KEY= 6 | ELEVEN_API_KEY= 7 | -------------------------------------------------------------------------------- /agent.py: -------------------------------------------------------------------------------- 1 | import re 2 | import random 3 | import logging 4 | import aiohttp 5 | from datetime import datetime 6 | from typing import Annotated 7 | 8 | from dotenv import load_dotenv 9 | from livekit.agents import ( 10 | AutoSubscribe, 11 | JobContext, 12 | JobProcess, 13 | WorkerOptions, 14 | cli, 15 | llm, 16 | metrics, 17 | ) 18 | from livekit.agents.pipeline import AgentCallContext, VoicePipelineAgent 19 | from livekit.rtc import ParticipantKind 20 | from livekit.plugins import openai, deepgram, elevenlabs, silero, turn_detector 21 | 22 | 23 | load_dotenv(dotenv_path=".env.local") 24 | logger = logging.getLogger("voice-agent") 25 | 26 | 27 | class AssistantFnc(llm.FunctionContext): 28 | # the llm.ai_callable decorator marks this function as a tool available to the LLM 29 | # by default, it'll use the docstring as the function's description 30 | @llm.ai_callable() 31 | async def get_weather( 32 | self, 33 | # by using the Annotated type, arg description and type are available to the LLM 34 | location: Annotated[ 35 | str, llm.TypeInfo(description="The location to get the weather for") 36 | ], 37 | ): 38 | """Called when the user asks about the weather. This function will return the weather for the given location.""" 39 | # Clean the location string of special characters 40 | location = re.sub(r"[^a-zA-Z0-9]+", " ", location).strip() 41 | 42 | # When a function call is running, there are a couple of options to inform the user 43 | # that it might take awhile: 44 | # Option 1: you can use .say filler message immediately after the call is triggered 45 | # Option 2: you can prompt the agent to return a text response when it's making a function call 46 | agent = AgentCallContext.get_current().agent 47 | 48 | if ( 49 | not agent.chat_ctx.messages 50 | or agent.chat_ctx.messages[-1].role != "assistant" 51 | ): 52 | # skip if assistant already said something 53 | filler_messages = [ 54 | "Let me check the weather in {location} for you.", 55 | "Let me see what the weather is like in {location} right now.", 56 | # LLM will complete this sentence if it is added to the end of the chat context 57 | "The current weather in {location} is ", 58 | ] 59 | message = random.choice(filler_messages).format(location=location) 60 | logger.info(f"saying filler message: {message}") 61 | 62 | # NOTE: set add_to_chat_ctx=True will add the message to the end 63 | # of the chat context of the function call for answer synthesis 64 | speech_handle = await agent.say(message, add_to_chat_ctx=True) # noqa: F841 65 | 66 | logger.info(f"getting weather for {location}") 67 | url = f"https://wttr.in/{location}?format=%C+%t" 68 | weather_data = "" 69 | async with aiohttp.ClientSession() as session: 70 | async with session.get(url) as response: 71 | if response.status == 200: 72 | weather_data = (f"The weather in {location} is {await response.text()}.") 73 | logger.info(f"weather data: {weather_data}") 74 | else: 75 | raise f"Failed to get weather data, status code: {response.status}" 76 | 77 | # (optional) To wait for the speech to finish before giving results of the function call 78 | # await speech_handle.join() 79 | return weather_data 80 | 81 | @llm.ai_callable() 82 | def get_time(self): 83 | """called to retrieve the current local time""" 84 | return datetime.now().strftime("%H:%M:%S") 85 | 86 | 87 | def prewarm(proc: JobProcess): 88 | proc.userdata["vad"] = silero.VAD.load() 89 | 90 | 91 | async def entrypoint(ctx: JobContext): 92 | initial_ctx = llm.ChatContext().append( 93 | role="system", 94 | text=( 95 | "You are a voice assistant created by LiveKit. Your interface with users will be voice. " 96 | "You should use short and concise responses, and avoiding usage of unpronouncable punctuation. " 97 | "You were created as a demo to showcase the capabilities of LiveKit's agents framework." 98 | ), 99 | ) 100 | 101 | logger.info(f"connecting to room {ctx.room.name}") 102 | await ctx.connect(auto_subscribe=AutoSubscribe.AUDIO_ONLY) 103 | 104 | # Wait for the first participant to connect 105 | participant = await ctx.wait_for_participant() 106 | logger.info(f"starting voice assistant for participant {participant.identity}") 107 | logger.info(f"participant.name: {participant.name}") 108 | logger.info(f"participant.attributes: {participant.attributes}") 109 | 110 | dg_model = "nova-2-general" 111 | if participant.kind == ParticipantKind.PARTICIPANT_KIND_SIP: 112 | # use a model optimized for telephony 113 | dg_model = "nova-2-phonecall" 114 | 115 | # This project is configured to use Deepgram STT, OpenAI LLM and ElevenLabs TTS plugins 116 | # Other providers exist like Cerebras, Cartesia, Groq, Play.ht, Rime, and more 117 | # Learn more and pick the best one for your app: 118 | # https://docs.livekit.io/agents/plugins 119 | agent = VoicePipelineAgent( 120 | vad=ctx.proc.userdata["vad"], 121 | stt=deepgram.STT(model=dg_model), 122 | llm=openai.LLM(model="gpt-4o-mini"), 123 | tts=elevenlabs.TTS(), 124 | turn_detector=turn_detector.EOUModel(), 125 | # minimum delay for endpointing, used when turn detector believes the user is done with their turn 126 | min_endpointing_delay=0.5, 127 | # maximum delay for endpointing, used when turn detector does not believe the user is done with their turn 128 | max_endpointing_delay=5.0, 129 | chat_ctx=initial_ctx, 130 | fnc_ctx=AssistantFnc(), 131 | ) 132 | 133 | usage_collector = metrics.UsageCollector() 134 | 135 | @agent.on("metrics_collected") 136 | def on_metrics_collected(agent_metrics: metrics.AgentMetrics): 137 | metrics.log_metrics(agent_metrics) 138 | usage_collector.collect(agent_metrics) 139 | 140 | async def log_usage(): 141 | summary = usage_collector.get_summary() 142 | logger.info(f"Summary Usage: {summary}") 143 | 144 | # At shutdown, generate and log the summary from the usage collector 145 | ctx.add_shutdown_callback(log_usage) 146 | 147 | agent.start(ctx.room, participant) 148 | 149 | # The agent greeting when the user joins 150 | await agent.say("Hey, how can I help you today?", allow_interruptions=True) 151 | 152 | 153 | if __name__ == "__main__": 154 | cli.run_app( 155 | WorkerOptions( 156 | entrypoint_fnc=entrypoint, 157 | prewarm_fnc=prewarm, 158 | agent_name="inbound-agent", 159 | ), 160 | ) 161 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # LiveKit Voice Agent 2 | 3 | A production-ready voice agent implementation using LiveKit and Python, featuring advanced conversational AI capabilities and optional telephony integration. 4 | 5 | ## Architecture Overview 6 | 7 | ``` 8 | ┌─────────────────────────────────────────────────────────────────────────────────┐ 9 | │ LiveKit Voice Agent Architecture │ 10 | └─────────────────────────────────────────────────────────────────────────────────┘ 11 | 12 | ┌─────────────────┐ ┌─────────────────┐ ┌─────────────────┐ 13 | │ Web Client │ │ Phone System │ │ Mobile App │ 14 | │ (Next.js) │ │ (Twilio) │ │ (React) │ 15 | └─────────┬───────┘ └─────────┬───────┘ └─────────┬───────┘ 16 | │ │ │ 17 | └──────────────────────┼──────────────────────┘ 18 | │ 19 | ┌────────────▼────────────┐ 20 | │ LiveKit Server │ 21 | │ (WebRTC Gateway) │ 22 | └────────────┬────────────┘ 23 | │ 24 | ┌────────────▼────────────┐ 25 | │ Voice Pipeline Agent │ 26 | │ │ 27 | │ ┌─────────────────┐ │ 28 | │ │ Turn Detection │ │ 29 | │ │ (Silero) │ │ 30 | │ └─────────────────┘ │ 31 | │ │ 32 | │ ┌─────────────────┐ │ 33 | │ │ Audio Pipeline │ │ 34 | │ │ ┌─────────────┐ │ │ 35 | │ │ │ Krisp │ │ │ 36 | │ │ │ (Noise │ │ │ 37 | │ │ │ Cancel) │ │ │ 38 | │ │ └─────────────┘ │ │ 39 | │ └─────────────────┘ │ 40 | └────────────┬────────────┘ 41 | │ 42 | ┌────────────────────────┼────────────────────────┐ 43 | │ │ │ 44 | ▼ ▼ ▼ 45 | ┌──────────────┐ ┌──────────────┐ ┌──────────────┐ 46 | │ Speech-to- │ │ Language │ │ Text-to- │ 47 | │ Text (STT) │ │ Model (LLM) │ │ Speech (TTS) │ 48 | │ │ │ │ │ │ 49 | │ Deepgram API │ │ OpenAI API │ │ ElevenLabs │ 50 | │ │ │ │ │ API │ 51 | └──────┬───────┘ └──────┬───────┘ └──────┬───────┘ 52 | │ │ │ 53 | │ ┌─────────▼────────┐ │ 54 | │ │ Function Calling │ │ 55 | │ │ │ │ 56 | │ │ ┌──────────────┐ │ │ 57 | │ │ │ Weather │ │ │ 58 | │ │ │ Service │ │ │ 59 | │ │ └──────────────┘ │ │ 60 | │ │ │ │ 61 | │ │ ┌──────────────┐ │ │ 62 | │ │ │ Clock │ │ │ 63 | │ │ │ Service │ │ │ 64 | │ │ └──────────────┘ │ │ 65 | │ │ │ │ 66 | │ │ ┌──────────────┐ │ │ 67 | │ │ │ Custom │ │ │ 68 | │ │ │ Tools │ │ │ 69 | │ │ └──────────────┘ │ │ 70 | │ └──────────────────┘ │ 71 | │ │ 72 | └───────────────────┐ ┌─────────────────────┘ 73 | │ │ 74 | ┌──────▼─────▼──────┐ 75 | │ Logging & │ 76 | │ Analytics │ 77 | │ │ 78 | │ • Usage Metrics │ 79 | │ • Conversation │ 80 | │ Summaries │ 81 | │ • Performance │ 82 | │ Monitoring │ 83 | └───────────────────┘ 84 | 85 | ┌─────────────────────────────────────────────────────────────────────────────────┐ 86 | │ Data Flow Process │ 87 | └─────────────────────────────────────────────────────────────────────────────────┘ 88 | 89 | 1. Audio Input → 2. Noise Cancellation → 3. Speech Detection → 4. STT Processing 90 | ↓ 91 | 8. Audio Output ← 7. TTS Generation ← 6. Response Generation ← 5. LLM Processing 92 | ↓ 93 | Function Execution 94 | (Weather, Clock, etc.) 95 | 96 | ┌─────────────────────────────────────────────────────────────────────────────────┐ 97 | │ Telephony Integration │ 98 | └─────────────────────────────────────────────────────────────────────────────────┘ 99 | 100 | Phone Call → Twilio SIP → LiveKit SIP Gateway → Voice Agent → Response Pipeline 101 | ↑ ↓ 102 | └──────────────── Audio Response ←─────────────────────────────┘ 103 | 104 | Regional SIP Configuration: 105 | • US East: 54.172.60.0, 54.244.51.0 106 | • US West: 54.171.127.192, 35.156.191.128 107 | • Europe: 54.171.127.200, 35.156.191.140 108 | • Asia Pacific: 54.169.127.128, 52.65.191.64 109 | ``` 110 | 111 | ## How It Works 112 | 113 | ### 1. **Connection Establishment** 114 | - Users connect via web browsers, mobile apps, or phone calls 115 | - LiveKit server handles WebRTC connections and SIP integration 116 | - Agent automatically detects connection type and optimizes accordingly 117 | 118 | ### 2. **Audio Processing Pipeline** 119 | - **Input**: Raw audio from user's microphone or phone 120 | - **Noise Cancellation**: Krisp AI removes background noise 121 | - **Turn Detection**: Silero VAD detects when user starts/stops speaking 122 | - **Speech-to-Text**: Deepgram converts speech to text in real-time 123 | 124 | ### 3. **Intelligent Processing** 125 | - **Language Understanding**: OpenAI processes user intent 126 | - **Function Calling**: Agent can execute tools (weather, time, custom functions) 127 | - **Context Management**: Maintains conversation history and state 128 | 129 | ### 4. **Response Generation** 130 | - **Text Generation**: LLM creates appropriate responses 131 | - **Text-to-Speech**: ElevenLabs converts text to natural speech 132 | - **Audio Delivery**: Processed audio sent back to user 133 | 134 | ### 5. **Monitoring & Analytics** 135 | - Real-time performance metrics 136 | - Conversation logging and summaries 137 | - Usage analytics and optimization insights 138 | 139 | ## Features 140 | 141 | - **Intelligent Turn Detection** - Natural conversation flow with automatic speech detection 142 | - **Function Calling** - Extensible tool integration including: 143 | - Weather information retrieval 144 | - Real-time clock functionality 145 | - **Comprehensive Logging** - Usage analytics and conversation summaries 146 | - **Telephony Integration** - Inbound call support via Twilio SIP trunking 147 | - **Audio Enhancement** - Krisp noise cancellation for crystal-clear communication 148 | - **Optimized Models** - Automatic model switching for telephony vs. web-based interactions 149 | 150 | ## Prerequisites 151 | 152 | - Python 3.8 or higher 153 | - LiveKit Cloud account or self-hosted LiveKit server 154 | - API keys for required services (OpenAI, ElevenLabs, Deepgram) 155 | - Optional: Twilio account for telephony features 156 | 157 | ## Installation 158 | 159 | ### Quick Start 160 | 161 | 1. **Clone and navigate to the repository:** 162 | 163 | ```bash 164 | git clone https://github.com/wiljansantiago/livekit-voice-agent.git 165 | cd livekit-voice-agent 166 | ``` 167 | 168 | 2. **Set up Python environment:** 169 | 170 | **Linux/macOS:** 171 | 172 | ```bash 173 | python3 -m venv venv 174 | source venv/bin/activate 175 | pip install -r requirements.txt 176 | python3 agent.py download-files 177 | ``` 178 | 179 | **Windows:** 180 | 181 | ```bash 182 | python3 -m venv venv 183 | venv\Scripts\activate 184 | pip install -r requirements.txt 185 | python3 agent.py download-files 186 | ``` 187 | 188 | ### Configuration 189 | 190 | 1. **Environment Setup:** 191 | Copy the example environment file and configure your API credentials: 192 | 193 | ```bash 194 | cp .env.example .env.local 195 | ``` 196 | 197 | 2. **Required Environment Variables:** 198 | ``` 199 | LIVEKIT_URL=your_livekit_server_url 200 | LIVEKIT_API_KEY=your_api_key 201 | LIVEKIT_API_SECRET=your_api_secret 202 | OPENAI_API_KEY=your_openai_key 203 | ELEVEN_API_KEY=your_elevenlabs_key 204 | DEEPGRAM_API_KEY=your_deepgram_key 205 | ``` 206 | 207 | 3. **Automated Configuration (Optional):** 208 | If using LiveKit Cloud, you can auto-configure using the CLI: 209 | 210 | ```bash 211 | lk app env 212 | ``` 213 | 214 | ## Usage 215 | 216 | ### Development Mode 217 | 218 | Start the agent in development mode: 219 | 220 | ```bash 221 | python3 agent.py dev 222 | ``` 223 | 224 | ## Telephony Integration (Optional) 225 | 226 | Enable inbound phone calls through Twilio SIP integration. 227 | 228 | ### Prerequisites 229 | 230 | - LiveKit CLI installed and authenticated 231 | - Twilio account with phone number 232 | - SIP trunk configuration 233 | 234 | ### Installation Steps 235 | 236 | 1. **Install LiveKit CLI (macOS):** 237 | 238 | ```bash 239 | brew update && brew install livekit-cli 240 | ``` 241 | 242 | 2. **Authenticate with LiveKit Cloud:** 243 | 244 | ```bash 245 | lk cloud auth 246 | ``` 247 | 248 | ### Twilio Configuration 249 | 250 | 1. **Create Twilio Resources:** 251 | - Sign up for a Twilio account 252 | - Purchase a phone number 253 | - Create a new SIP trunk in the Twilio Console 254 | 255 | 2. **Configure SIP Trunk:** 256 | - Navigate to: Elastic SIP Trunking → SIP Trunks → Create 257 | - Add Origination URI: `;transport=tcp` 258 | - Associate your phone number with priority 1, weight 1 259 | 260 | 3. **Deploy LiveKit SIP Configuration:** 261 | 262 | **Create Inbound Trunk:** 263 | 264 | ```bash 265 | lk sip inbound create inbound-trunk.json 266 | ``` 267 | 268 | **Create Dispatch Rule:** 269 | 270 | ```bash 271 | lk sip dispatch create dispatch-rule.json 272 | ``` 273 | 274 | ### Regional Configuration 275 | 276 | Update `inbound-trunk.json` with appropriate Twilio SIP signaling IP addresses for your region. The default configuration includes US IP addresses. 277 | 278 | ## Architecture 279 | 280 | - **Agent Core** - Main conversation logic and state management 281 | - **Function Registry** - Extensible tool calling system 282 | - **Audio Pipeline** - Real-time audio processing with noise cancellation 283 | - **SIP Integration** - Telephony gateway for inbound calls 284 | - **Logging System** - Comprehensive usage and performance analytics 285 | 286 | ## Support 287 | 288 | For issues and questions: 289 | - Check the [LiveKit Documentation](https://docs.livekit.io/) 290 | - Review existing GitHub issues 291 | - Contact support through your LiveKit Cloud dashboard 292 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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