This example demonstrates how to build a multilingual voice agent that can switch between languages mid-call by updating ElevenLabs TTS and Deepgram STT on the fly. The agent greets callers in English, switches to Spanish, French, German, or Italian when asked, and replies with a native greeting in the new language.
Prerequisites
- Add a
.envin this directory with your LiveKit and provider credentials:LIVEKIT_URL=your_livekit_urlLIVEKIT_API_KEY=your_api_keyLIVEKIT_API_SECRET=your_api_secretDEEPGRAM_API_KEY=your_deepgram_keyELEVENLABS_API_KEY=your_elevenlabs_key - Install dependencies:pip install python-dotenv "livekit-agents[silero,deepgram,elevenlabs]"
Load environment, logging, and define an AgentServer
Start by importing the necessary modules, loading your environment, and configuring logging for the agent.
import loggingfrom dotenv import load_dotenvfrom livekit.agents import JobContext, JobProcess, Agent, AgentSession, AgentServer, cli, inference, function_toolfrom livekit.plugins import deepgram, elevenlabs, sileroload_dotenv()logger = logging.getLogger("language-switcher")logger.setLevel(logging.INFO)server = AgentServer()
Prewarm VAD and define the language-switcher agent
Preload VAD once per process to reduce connection latency. Configure the RTC session with Deepgram STT, ElevenLabs TTS, and an inference LLM.
import loggingfrom dotenv import load_dotenvfrom livekit.agents import JobContext, JobProcess, Agent, AgentSession, AgentServer, cli, inference, function_toolfrom livekit.plugins import deepgram, elevenlabs, sileroload_dotenv()logger = logging.getLogger("language-switcher")logger.setLevel(logging.INFO)server = AgentServer()def prewarm(proc: JobProcess):proc.userdata["vad"] = silero.VAD.load()server.setup_fnc = prewarmclass LanguageSwitcherAgent(Agent):def __init__(self) -> None:super().__init__(instructions="""You are a helpful assistant communicating through voice.You can switch to a different language if asked.Don't use any unpronounceable characters.""")self.current_language = "en"self.language_names = {"en": "English","es": "Spanish","fr": "French","de": "German","it": "Italian",}self.deepgram_language_codes = {"en": "en","es": "es","fr": "fr-CA","de": "de","it": "it",}self.greetings = {"en": "Hello! I'm now speaking in English. How can I help you today?","es": "¡Hola! Ahora estoy hablando en español. ¿Cómo puedo ayudarte hoy?","fr": "Bonjour! Je parle maintenant en français. Comment puis-je vous aider aujourd'hui?","de": "Hallo! Ich spreche jetzt Deutsch. Wie kann ich Ihnen heute helfen?","it": "Ciao! Ora sto parlando in italiano. Come posso aiutarti oggi?",}async def on_enter(self):await self.session.say("Hi there! I can speak in multiple languages including Spanish, French, German, and Italian. ""Just ask me to switch to any of these languages. How can I help you today?")@server.rtc_session()async def entrypoint(ctx: JobContext):ctx.log_context_fields = {"room": ctx.room.name}session = AgentSession(stt=deepgram.STT(model="nova-2-general", language="en"),llm=inference.LLM(model="openai/gpt-4o"),tts=elevenlabs.TTS(model="eleven_turbo_v2_5", language="en"),vad=ctx.proc.userdata["vad"],preemptive_generation=True,)await session.start(agent=LanguageSwitcherAgent(), room=ctx.room)await ctx.connect()
Add the function tools to switch languages
Next we'll add a helper to swap STT/TTS languages, and function tools that let the LLM trigger language changes.
import loggingfrom dotenv import load_dotenvfrom livekit.agents import JobContext, JobProcess, Agent, AgentSession, AgentServer, cli, inference, function_toolfrom livekit.plugins import deepgram, elevenlabs, sileroload_dotenv()logger = logging.getLogger("language-switcher")logger.setLevel(logging.INFO)server = AgentServer()def prewarm(proc: JobProcess):proc.userdata["vad"] = silero.VAD.load()server.setup_fnc = prewarmclass LanguageSwitcherAgent(Agent):def __init__(self) -> None:super().__init__(instructions="""You are a helpful assistant communicating through voice.You can switch to a different language if asked.Don't use any unpronounceable characters.""")self.current_language = "en"self.language_names = {"en": "English","es": "Spanish","fr": "French","de": "German","it": "Italian",}self.deepgram_language_codes = {"en": "en","es": "es","fr": "fr-CA","de": "de","it": "it",}self.greetings = {"en": "Hello! I'm now speaking in English. How can I help you today?","es": "¡Hola! Ahora estoy hablando en español. ¿Cómo puedo ayudarte hoy?","fr": "Bonjour! Je parle maintenant en français. Comment puis-je vous aider aujourd'hui?","de": "Hallo! Ich spreche jetzt Deutsch. Wie kann ich Ihnen heute helfen?","it": "Ciao! Ora sto parlando in italiano. Come posso aiutarti oggi?",}async def on_enter(self):await self.session.say("Hi there! I can speak in multiple languages including Spanish, French, German, and Italian. ""Just ask me to switch to any of these languages. How can I help you today?")async def _switch_language(self, language_code: str) -> None:"""Helper method to switch the language"""if language_code == self.current_language:await self.session.say(f"I'm already speaking in {self.language_names[language_code]}.")returnif self.session.tts is not None:self.session.tts.update_options(language=language_code)if self.session.stt is not None:deepgram_language = self.deepgram_language_codes.get(language_code, language_code)self.session.stt.update_options(language=deepgram_language)self.current_language = language_codeawait self.session.say(self.greetings[language_code])@function_toolasync def switch_to_english(self):"""Switch to speaking English"""await self._switch_language("en")@function_toolasync def switch_to_spanish(self):"""Switch to speaking Spanish"""await self._switch_language("es")@function_toolasync def switch_to_french(self):"""Switch to speaking French"""await self._switch_language("fr")@function_toolasync def switch_to_german(self):"""Switch to speaking German"""await self._switch_language("de")@function_toolasync def switch_to_italian(self):"""Switch to speaking Italian"""await self._switch_language("it")@server.rtc_session()async def entrypoint(ctx: JobContext):ctx.log_context_fields = {"room": ctx.room.name}session = AgentSession(stt=deepgram.STT(model="nova-2-general", language="en"),llm=inference.LLM(model="openai/gpt-4o"),tts=elevenlabs.TTS(model="eleven_turbo_v2_5", language="en"),vad=ctx.proc.userdata["vad"],preemptive_generation=True,)await session.start(agent=LanguageSwitcherAgent(), room=ctx.room)await ctx.connect()
Run the server
Use the CLI runner to start the agent server so it can respond to language-change requests.
import loggingfrom dotenv import load_dotenvfrom livekit.agents import JobContext, JobProcess, Agent, AgentSession, AgentServer, cli, inference, function_toolfrom livekit.plugins import deepgram, elevenlabs, sileroload_dotenv()logger = logging.getLogger("language-switcher")logger.setLevel(logging.INFO)server = AgentServer()def prewarm(proc: JobProcess):proc.userdata["vad"] = silero.VAD.load()server.setup_fnc = prewarmclass LanguageSwitcherAgent(Agent):def __init__(self) -> None:super().__init__(instructions="""You are a helpful assistant communicating through voice.You can switch to a different language if asked.Don't use any unpronounceable characters.""")self.current_language = "en"self.language_names = {"en": "English","es": "Spanish","fr": "French","de": "German","it": "Italian",}self.deepgram_language_codes = {"en": "en","es": "es","fr": "fr-CA","de": "de","it": "it",}self.greetings = {"en": "Hello! I'm now speaking in English. How can I help you today?","es": "¡Hola! Ahora estoy hablando en español. ¿Cómo puedo ayudarte hoy?","fr": "Bonjour! Je parle maintenant en français. Comment puis-je vous aider aujourd'hui?","de": "Hallo! Ich spreche jetzt Deutsch. Wie kann ich Ihnen heute helfen?","it": "Ciao! Ora sto parlando in italiano. Come posso aiutarti oggi?",}async def on_enter(self):await self.session.say("Hi there! I can speak in multiple languages including Spanish, French, German, and Italian. ""Just ask me to switch to any of these languages. How can I help you today?")async def _switch_language(self, language_code: str) -> None:"""Helper method to switch the language"""if language_code == self.current_language:await self.session.say(f"I'm already speaking in {self.language_names[language_code]}.")returnif self.session.tts is not None:self.session.tts.update_options(language=language_code)if self.session.stt is not None:deepgram_language = self.deepgram_language_codes.get(language_code, language_code)self.session.stt.update_options(language=deepgram_language)self.current_language = language_codeawait self.session.say(self.greetings[language_code])@function_toolasync def switch_to_english(self):"""Switch to speaking English"""await self._switch_language("en")@function_toolasync def switch_to_spanish(self):"""Switch to speaking Spanish"""await self._switch_language("es")@function_toolasync def switch_to_french(self):"""Switch to speaking French"""await self._switch_language("fr")@function_toolasync def switch_to_german(self):"""Switch to speaking German"""await self._switch_language("de")@function_toolasync def switch_to_italian(self):"""Switch to speaking Italian"""await self._switch_language("it")@server.rtc_session()async def entrypoint(ctx: JobContext):ctx.log_context_fields = {"room": ctx.room.name}session = AgentSession(stt=deepgram.STT(model="nova-2-general", language="en"),llm=inference.LLM(model="openai/gpt-4o"),tts=elevenlabs.TTS(model="eleven_turbo_v2_5", language="en"),vad=ctx.proc.userdata["vad"],preemptive_generation=True,)await session.start(agent=LanguageSwitcherAgent(), room=ctx.room)await ctx.connect()if __name__ == "__main__":cli.run_app(server)
Run it
python elevenlabs_change_language.py console
Try saying:
- "Switch to Spanish"
- "Can you speak French?"
- "Let's talk in German"
- "Change to Italian"
Supported languages
| Language | Code | Deepgram Code | Example Phrase |
|---|---|---|---|
| English | en | en | "Hello! How can I help you?" |
| Spanish | es | es | "¡Hola! ¿Cómo puedo ayudarte?" |
| French | fr | fr-CA | "Bonjour! Comment puis-je vous aider?" |
| German | de | de | "Hallo! Wie kann ich Ihnen helfen?" |
| Italian | it | it | "Ciao! Come posso aiutarti?" |
How it works
- The agent greets in English and waits for a language change request.
- A function tool routes to
_switch_language(), which updates both TTS and STT viaupdate_options(). - The agent tracks the current language to avoid redundant switches.
- A native greeting confirms the change, and the rest of the conversation stays in the selected language until switched again.
Full example
import loggingfrom dotenv import load_dotenvfrom livekit.agents import JobContext, JobProcess, Agent, AgentSession, AgentServer, cli, inference, function_toolfrom livekit.plugins import deepgram, elevenlabs, sileroload_dotenv()logger = logging.getLogger("language-switcher")logger.setLevel(logging.INFO)server = AgentServer()class LanguageSwitcherAgent(Agent):def __init__(self) -> None:super().__init__(instructions="""You are a helpful assistant communicating through voice.You can switch to a different language if asked.Don't use any unpronounceable characters.""")self.current_language = "en"self.language_names = {"en": "English","es": "Spanish","fr": "French","de": "German","it": "Italian",}self.deepgram_language_codes = {"en": "en","es": "es","fr": "fr-CA","de": "de","it": "it",}self.greetings = {"en": "Hello! I'm now speaking in English. How can I help you today?","es": "¡Hola! Ahora estoy hablando en español. ¿Cómo puedo ayudarte hoy?","fr": "Bonjour! Je parle maintenant en français. Comment puis-je vous aider aujourd'hui?","de": "Hallo! Ich spreche jetzt Deutsch. Wie kann ich Ihnen heute helfen?","it": "Ciao! Ora sto parlando in italiano. Come posso aiutarti oggi?",}async def on_enter(self):await self.session.say("Hi there! I can speak in multiple languages including Spanish, French, German, and Italian. ""Just ask me to switch to any of these languages. How can I help you today?")async def _switch_language(self, language_code: str) -> None:"""Helper method to switch the language"""if language_code == self.current_language:await self.session.say(f"I'm already speaking in {self.language_names[language_code]}.")returnif self.session.tts is not None:self.session.tts.update_options(language=language_code)if self.session.stt is not None:deepgram_language = self.deepgram_language_codes.get(language_code, language_code)self.session.stt.update_options(language=deepgram_language)self.current_language = language_codeawait self.session.say(self.greetings[language_code])@function_toolasync def switch_to_english(self):"""Switch to speaking English"""await self._switch_language("en")@function_toolasync def switch_to_spanish(self):"""Switch to speaking Spanish"""await self._switch_language("es")@function_toolasync def switch_to_french(self):"""Switch to speaking French"""await self._switch_language("fr")@function_toolasync def switch_to_german(self):"""Switch to speaking German"""await self._switch_language("de")@function_toolasync def switch_to_italian(self):"""Switch to speaking Italian"""await self._switch_language("it")def prewarm(proc: JobProcess):proc.userdata["vad"] = silero.VAD.load()server.setup_fnc = prewarm@server.rtc_session()async def entrypoint(ctx: JobContext):ctx.log_context_fields = {"room": ctx.room.name}session = AgentSession(stt=deepgram.STT(model="nova-2-general", language="en"),llm=inference.LLM(model="openai/gpt-4o"),tts=elevenlabs.TTS(model="eleven_turbo_v2_5", language="en"),vad=ctx.proc.userdata["vad"],preemptive_generation=True,)await session.start(agent=LanguageSwitcherAgent(), room=ctx.room)await ctx.connect()if __name__ == "__main__":cli.run_app(server)
Example conversation
Agent: "Hi there! I can speak in multiple languages..."User: "Can you speak Spanish?"Agent: "¡Hola! Ahora estoy hablando en español. ¿Cómo puedo ayudarte hoy?"User: "¿Cuál es el clima?"Agent: [Responds in Spanish about the weather]User: "Now switch to French"Agent: "Bonjour! Je parle maintenant en français. Comment puis-je vous aider aujourd'hui?"