Tool use with Live API

Tool use allows Live API to go beyond just conversation by enabling it to perform actions in the real-world and pull in external context while maintaining a real time connection. You can define tools such as Function calling, Code execution, and Google Search with the Live API.

Overview of supported tools

Here's a brief overview of the available tools for each model:

Tool Cascaded models
gemini-2.0-flash-live-001		 gemini-2.5-flash-preview-native-audio-dialog gemini-2.5-flash-exp-native-audio-thinking-dialog
Search Yes Yes Yes
Function calling Yes Yes No
Code execution Yes No No
Url context Yes No No

Function calling

Live API supports function calling, just like regular content generation requests. Function calling lets the Live API interact with external data and programs, greatly increasing what your applications can accomplish.

You can define function declarations as part of the session configuration. After receiving tool calls, the client should respond with a list of FunctionResponse objects using the session.send_tool_response method.

See the Function calling tutorial to learn more.

Python 

import asyncio
from google import genai
from google.genai import types

client = genai.Client(api_key="GEMINI_API_KEY")
model = "gemini-2.0-flash-live-001"

# Simple function definitions
turn_on_the_lights = {"name": "turn_on_the_lights"}
turn_off_the_lights = {"name": "turn_off_the_lights"}

tools = [{"function_declarations": [turn_on_the_lights, turn_off_the_lights]}]
config = {"response_modalities": ["TEXT"], "tools": tools}

async def main():
    async with client.aio.live.connect(model=model, config=config) as session:
        prompt = "Turn on the lights please"
        await session.send_client_content(turns={"parts": [{"text": prompt}]})

        async for chunk in session.receive():
            if chunk.server_content:
                if chunk.text is not None:
                    print(chunk.text)
            elif chunk.tool_call:
                function_responses = []
                for fc in chunk.tool_call.function_calls:
                    function_response = types.FunctionResponse(
                        id=fc.id,
                        name=fc.name,
                        response={ "result": "ok" } # simple, hard-coded function response
                    )
                    function_responses.append(function_response)

                await session.send_tool_response(function_responses=function_responses)

if __name__ == "__main__":
    asyncio.run(main())

JavaScript 

import { GoogleGenAI, Modality } from '@google/genai';

const ai = new GoogleGenAI({ apiKey: "GOOGLE_API_KEY" });
const model = 'gemini-2.0-flash-live-001';

// Simple function definitions
const turn_on_the_lights = { name: "turn_on_the_lights" } // , description: '...', parameters: { ... }
const turn_off_the_lights = { name: "turn_off_the_lights" }

const tools = [{ functionDeclarations: [turn_on_the_lights, turn_off_the_lights] }]

const config = {
  responseModalities: [Modality.TEXT],
  tools: tools
}

async function live() {
  const responseQueue = [];

  async function waitMessage() {
    let done = false;
    let message = undefined;
    while (!done) {
      message = responseQueue.shift();
      if (message) {
        done = true;
      } else {
        await new Promise((resolve) => setTimeout(resolve, 100));
      }
    }
    return message;
  }

  async function handleTurn() {
    const turns = [];
    let done = false;
    while (!done) {
      const message = await waitMessage();
      turns.push(message);
      if (message.serverContent && message.serverContent.turnComplete) {
        done = true;
      } else if (message.toolCall) {
        done = true;
      }
    }
    return turns;
  }

  const session = await ai.live.connect({
    model: model,
    callbacks: {
      onopen: function () {
        console.debug('Opened');
      },
      onmessage: function (message) {
        responseQueue.push(message);
      },
      onerror: function (e) {
        console.debug('Error:', e.message);
      },
      onclose: function (e) {
        console.debug('Close:', e.reason);
      },
    },
    config: config,
  });

  const inputTurns = 'Turn on the lights please';
  session.sendClientContent({ turns: inputTurns });

  let turns = await handleTurn();

  for (const turn of turns) {
    if (turn.serverContent && turn.serverContent.modelTurn && turn.serverContent.modelTurn.parts) {
      for (const part of turn.serverContent.modelTurn.parts) {
        if (part.text) {
          console.debug('Received text: %s\n', part.text);
        }
      }
    }
    else if (turn.toolCall) {
      const functionResponses = [];
      for (const fc of turn.toolCall.functionCalls) {
        functionResponses.push({
          id: fc.id,
          name: fc.name,
          response: { result: "ok" } // simple, hard-coded function response
        });
      }

      console.debug('Sending tool response...\n');
      session.sendToolResponse({ functionResponses: functionResponses });
    }
  }

  // Check again for new messages
  turns = await handleTurn();

  for (const turn of turns) {
    if (turn.serverContent && turn.serverContent.modelTurn && turn.serverContent.modelTurn.parts) {
      for (const part of turn.serverContent.modelTurn.parts) {
        if (part.text) {
          console.debug('Received text: %s\n', part.text);
        }
      }
    }
  }

  session.close();
}

async function main() {
  await live().catch((e) => console.error('got error', e));
}

main();

From a single prompt, the model can generate multiple function calls and the code necessary to chain their outputs. This code executes in a sandbox environment, generating subsequent BidiGenerateContentToolCall messages.

Asynchronous function calling

Function calling executes sequentially by default, meaning execution pauses until the results of each function call are available. This ensures sequential processing, which means you won't be able to continue interacting with the model while the functions are being run.

If you don't want to block the conversation, you can tell the model to run the functions asynchronously. To do so, you first need to add a behavior to the function definitions:

Python 

  # Non-blocking function definitions
  turn_on_the_lights = {"name": "turn_on_the_lights", "behavior": "NON_BLOCKING"} # turn_on_the_lights will run asynchronously
  turn_off_the_lights = {"name": "turn_off_the_lights"} # turn_off_the_lights will still pause all interactions with the model

JavaScript 

import { GoogleGenAI, Modality, Behavior } from '@google/genai';

// Non-blocking function definitions
const turn_on_the_lights = {name: "turn_on_the_lights", behavior: Behavior.NON_BLOCKING}

// Blocking function definitions
const turn_off_the_lights = {name: "turn_off_the_lights"}

const tools = [{ functionDeclarations: [turn_on_the_lights, turn_off_the_lights] }]

NON-BLOCKING ensures the function runs asynchronously while you can continue interacting with the model.

Then you need to tell the model how to behave when it receives the FunctionResponse using the scheduling parameter. It can either:

  • Interrupt what it's doing and tell you about the response it got right away (scheduling="INTERRUPT"),
  • Wait until it's finished with what it's currently doing (scheduling="WHEN_IDLE"),

  • Or do nothing and use that knowledge later on in the discussion (scheduling="SILENT")

Python 

# for a non-blocking function definition, apply scheduling in the function response:
  function_response = types.FunctionResponse(
      id=fc.id,
      name=fc.name,
      response={
          "result": "ok",
          "scheduling": "INTERRUPT" # Can also be WHEN_IDLE or SILENT
      }
  )

JavaScript 

import { GoogleGenAI, Modality, Behavior, FunctionResponseScheduling } from '@google/genai';

// for a non-blocking function definition, apply scheduling in the function response:
const functionResponse = {
  id: fc.id,
  name: fc.name,
  response: {
    result: "ok",
    scheduling: FunctionResponseScheduling.INTERRUPT  // Can also be WHEN_IDLE or SILENT
  }
}

Code execution

You can define code execution as part of the session configuration. This lets the Live API generate and execute Python code and dynamically perform computations to benefit your results. See the Code execution tutorial to learn more.

Python 

import asyncio
from google import genai
from google.genai import types

client = genai.Client(api_key="GEMINI_API_KEY")
model = "gemini-2.0-flash-live-001"

tools = [{'code_execution': {}}]
config = {"response_modalities": ["TEXT"], "tools": tools}

async def main():
    async with client.aio.live.connect(model=model, config=config) as session:
        prompt = "Compute the largest prime palindrome under 100000."
        await session.send_client_content(turns={"parts": [{"text": prompt}]})

        async for chunk in session.receive():
            if chunk.server_content:
                if chunk.text is not None:
                    print(chunk.text)

                model_turn = chunk.server_content.model_turn
                if model_turn:
                    for part in model_turn.parts:
                      if part.executable_code is not None:
                        print(part.executable_code.code)

                      if part.code_execution_result is not None:
                        print(part.code_execution_result.output)

if __name__ == "__main__":
    asyncio.run(main())

JavaScript 

import { GoogleGenAI, Modality } from '@google/genai';

const ai = new GoogleGenAI({ apiKey: "GOOGLE_API_KEY" });
const model = 'gemini-2.0-flash-live-001';

const tools = [{codeExecution: {}}]
const config = {
  responseModalities: [Modality.TEXT],
  tools: tools
}

async function live() {
  const responseQueue = [];

  async function waitMessage() {
    let done = false;
    let message = undefined;
    while (!done) {
      message = responseQueue.shift();
      if (message) {
        done = true;
      } else {
        await new Promise((resolve) => setTimeout(resolve, 100));
      }
    }
    return message;
  }

  async function handleTurn() {
    const turns = [];
    let done = false;
    while (!done) {
      const message = await waitMessage();
      turns.push(message);
      if (message.serverContent && message.serverContent.turnComplete) {
        done = true;
      } else if (message.toolCall) {
        done = true;
      }
    }
    return turns;
  }

  const session = await ai.live.connect({
    model: model,
    callbacks: {
      onopen: function () {
        console.debug('Opened');
      },
      onmessage: function (message) {
        responseQueue.push(message);
      },
      onerror: function (e) {
        console.debug('Error:', e.message);
      },
      onclose: function (e) {
        console.debug('Close:', e.reason);
      },
    },
    config: config,
  });

  const inputTurns = 'Compute the largest prime palindrome under 100000.';
  session.sendClientContent({ turns: inputTurns });

  const turns = await handleTurn();

  for (const turn of turns) {
    if (turn.serverContent && turn.serverContent.modelTurn && turn.serverContent.modelTurn.parts) {
      for (const part of turn.serverContent.modelTurn.parts) {
        if (part.text) {
          console.debug('Received text: %s\n', part.text);
        }
        else if (part.executableCode) {
          console.debug('executableCode: %s\n', part.executableCode.code);
        }
        else if (part.codeExecutionResult) {
          console.debug('codeExecutionResult: %s\n', part.codeExecutionResult.output);
        }
      }
    }
  }

  session.close();
}

async function main() {
  await live().catch((e) => console.error('got error', e));
}

main();

You can enable Grounding with Google Search as part of the session configuration. This increases the Live API's accuracy and prevents hallucinations. See the Grounding tutorial to learn more.

Python 

import asyncio
from google import genai
from google.genai import types

client = genai.Client(api_key="GEMINI_API_KEY")
model = "gemini-2.0-flash-live-001"

tools = [{'google_search': {}}]
config = {"response_modalities": ["TEXT"], "tools": tools}

async def main():
    async with client.aio.live.connect(model=model, config=config) as session:
        prompt = "When did the last Brazil vs. Argentina soccer match happen?"
        await session.send_client_content(turns={"parts": [{"text": prompt}]})

        async for chunk in session.receive():
            if chunk.server_content:
                if chunk.text is not None:
                    print(chunk.text)

                # The model might generate and execute Python code to use Search
                model_turn = chunk.server_content.model_turn
                if model_turn:
                    for part in model_turn.parts:
                      if part.executable_code is not None:
                        print(part.executable_code.code)

                      if part.code_execution_result is not None:
                        print(part.code_execution_result.output)

if __name__ == "__main__":
    asyncio.run(main())

JavaScript 

import { GoogleGenAI, Modality } from '@google/genai';

const ai = new GoogleGenAI({ apiKey: "GOOGLE_API_KEY" });
const model = 'gemini-2.0-flash-live-001';

const tools = [{googleSearch: {}}]
const config = {
  responseModalities: [Modality.TEXT],
  tools: tools
}

async function live() {
  const responseQueue = [];

  async function waitMessage() {
    let done = false;
    let message = undefined;
    while (!done) {
      message = responseQueue.shift();
      if (message) {
        done = true;
      } else {
        await new Promise((resolve) => setTimeout(resolve, 100));
      }
    }
    return message;
  }

  async function handleTurn() {
    const turns = [];
    let done = false;
    while (!done) {
      const message = await waitMessage();
      turns.push(message);
      if (message.serverContent && message.serverContent.turnComplete) {
        done = true;
      } else if (message.toolCall) {
        done = true;
      }
    }
    return turns;
  }

  const session = await ai.live.connect({
    model: model,
    callbacks: {
      onopen: function () {
        console.debug('Opened');
      },
      onmessage: function (message) {
        responseQueue.push(message);
      },
      onerror: function (e) {
        console.debug('Error:', e.message);
      },
      onclose: function (e) {
        console.debug('Close:', e.reason);
      },
    },
    config: config,
  });

  const inputTurns = 'When did the last Brazil vs. Argentina soccer match happen?';
  session.sendClientContent({ turns: inputTurns });

  const turns = await handleTurn();

  for (const turn of turns) {
    if (turn.serverContent && turn.serverContent.modelTurn && turn.serverContent.modelTurn.parts) {
      for (const part of turn.serverContent.modelTurn.parts) {
        if (part.text) {
          console.debug('Received text: %s\n', part.text);
        }
        else if (part.executableCode) {
          console.debug('executableCode: %s\n', part.executableCode.code);
        }
        else if (part.codeExecutionResult) {
          console.debug('codeExecutionResult: %s\n', part.codeExecutionResult.output);
        }
      }
    }
  }

  session.close();
}

async function main() {
  await live().catch((e) => console.error('got error', e));
}

main();

Combining multiple tools

You can combine multiple tools within the Live API, increasing your application's capabilities even more:

Python 

prompt = """
Hey, I need you to do three things for me.

1. Compute the largest prime palindrome under 100000.
2. Then use Google Search to look up information about the largest earthquake in California the week of Dec 5 2024?
3. Turn on the lights

Thanks!
"""

tools = [
    {"google_search": {}},
    {"code_execution": {}},
    {"function_declarations": [turn_on_the_lights, turn_off_the_lights]},
]

config = {"response_modalities": ["TEXT"], "tools": tools}

# ... remaining model call

JavaScript 

const prompt = `Hey, I need you to do three things for me.

1. Compute the largest prime palindrome under 100000.
2. Then use Google Search to look up information about the largest earthquake in California the week of Dec 5 2024?
3. Turn on the lights

Thanks!
`

const tools = [
  { googleSearch: {} },
  { codeExecution: {} },
  { functionDeclarations: [turn_on_the_lights, turn_off_the_lights] }
]

const config = {
  responseModalities: [Modality.TEXT],
  tools: tools
}

// ... remaining model call

What's next