使用 Gemini API 进行函数调用

借助函数调用，您可以将模型连接到外部工具和 API。 模型不会生成文本回答，而是会确定何时调用特定函数，并提供执行实际操作所需的参数。这使得模型能够充当自然语言与现实世界中的行动和数据之间的桥梁。函数调用有 3 个主要应用场景：

  • 扩充知识：访问数据库、API 和知识库等外部来源的信息。
  • 扩展功能：使用外部工具执行计算，并扩展模型的功能限制，例如使用计算器或创建图表。
  • 执行操作：使用 API 与外部系统互动，例如安排预约、创建账单、发送电子邮件或控制智能家居设备。

Python

# This will only work for SDK newer than 2.0.0
from google import genai

schedule_meeting_function = {
    "type": "function",
    "name": "schedule_meeting",
    "description": "Schedules a meeting with specified attendees at a given time and date.",
    "parameters": {
        "type": "object",
        "properties": {
            "attendees": {"type": "array", "items": {"type": "string"}},
            "date": {"type": "string", "description": "Date (e.g., '2024-07-29')"},
            "time": {"type": "string", "description": "Time (e.g., '15:00')"},
            "topic": {"type": "string", "description": "The meeting topic."},
        },
        "required": ["attendees", "date", "time", "topic"],
    },
}

client = genai.Client()

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input="Schedule a meeting with Bob and Alice for 03/14/2025 at 10:00 AM about Q3 planning.",
    tools=[{"type": "function", **schedule_meeting_function}],
)

for step in interaction.steps:
    if step.type == "function_call":
        print(f"Function to call: {step.name}")
        print(f"Arguments: {step.arguments}")

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from '@google/genai';

const client = new GoogleGenAI({});

const scheduleMeetingFunction = {
  type: 'function',
  name: 'schedule_meeting',
  description: 'Schedules a meeting with specified attendees at a given time and date.',
  parameters: {
    type: 'object',
    properties: {
      attendees: { type: 'array', items: { type: 'string' } },
      date: { type: 'string', description: 'Date (e.g., "2024-07-29")' },
      time: { type: 'string', description: 'Time (e.g., "15:00")' },
      topic: { type: 'string', description: 'The meeting topic.' },
    },
    required: ['attendees', 'date', 'time', 'topic'],
  },
};

const interaction = await client.interactions.create({
  model: 'gemini-3-flash-preview',
  input: 'Schedule a meeting with Bob and Alice for 03/27/2025 at 10:00 AM about Q3 planning.',
  tools: [scheduleMeetingFunction],
});

for (const step of interaction.steps) {
  if (step.type === 'function_call') {
    console.log(`Function to call: ${step.name}`);
    console.log(`Arguments: ${JSON.stringify(step.arguments)}`);
  }
}

REST

# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -H "Api-Revision: 2026-05-20" \
  -d '{
    "model": "gemini-3-flash-preview",
    "input": "Schedule a meeting with Bob and Alice for 03/27/2025 at 10:00 AM about Q3 planning.",
    "tools": [{
        "type": "function",
        "name": "schedule_meeting",
        "description": "Schedules a meeting with specified attendees at a given time and date.",
        "parameters": {
          "type": "object",
          "properties": {
            "attendees": {"type": "array", "items": {"type": "string"}},
            "date": {"type": "string"},
            "time": {"type": "string"},
            "topic": {"type": "string"}
          },
          "required": ["attendees", "date", "time", "topic"]
        }
    }]
  }'

函数调用的工作原理

函数调用概览

函数调用涉及应用、模型和外部函数之间的结构化互动：

  1. 定义函数声明：向模型定义函数的名称、参数和用途。
  2. 使用函数声明调用 LLM：将用户提示与函数声明一起发送给模型。
  3. 执行函数代码（您的责任）：模型不会自行执行函数。提取名称和实参，并在应用中执行。
  4. 创建用户友好的回答：将结果发送回模型，以生成最终的、用户友好的回答。

此过程可在多个回合中重复进行。该模型支持在单个对话轮次中调用多个函数（并行函数调用）以及按顺序调用多个函数（组合式函数调用）。

第 1 步：定义函数声明

Python

# This will only work for SDK newer than 2.0.0
set_light_values_declaration = {
    "type": "function",
    "name": "set_light_values",
    "description": "Sets the brightness and color temperature of a light.",
    "parameters": {
        "type": "object",
        "properties": {
            "brightness": {
                "type": "integer",
                "description": "Light level from 0 to 100",
            },
            "color_temp": {
                "type": "string",
                "enum": ["daylight", "cool", "warm"],
                "description": "Color temperature",
            },
        },
        "required": ["brightness", "color_temp"],
    },
}

def set_light_values(brightness: int, color_temp: str) -> dict:
    """Set the brightness and color temperature of a room light."""
    return {"brightness": brightness, "colorTemperature": color_temp}

JavaScript

// This will only work for SDK newer than 2.0.0
const setLightValuesTool = {
  type: 'function',
  name: 'set_light_values',
  description: 'Sets the brightness and color temperature of a light.',
  parameters: {
    type: 'object',
    properties: {
      brightness: { type: 'number', description: 'Light level from 0 to 100' },
      color_temp: { type: 'string', enum: ['daylight', 'cool', 'warm'] },
    },
    required: ['brightness', 'color_temp'],
  },
};

function setLightValues(brightness, color_temp) {
  return { brightness: brightness, colorTemperature: color_temp };
}

第 2 步：使用函数声明调用模型

Python

# This will only work for SDK newer than 2.0.0
from google import genai

client = genai.Client()

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input="Turn the lights down to a romantic level",
    tools=[set_light_values_declaration],
)

# Find the function call step
fc_step = next(s for s in interaction.steps if s.type == "function_call")
print(fc_step)

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from '@google/genai';

const client = new GoogleGenAI({});

const interaction = await client.interactions.create({
  model: 'gemini-3-flash-preview',
  input: 'Turn the lights down to a romantic level',
  tools: [setLightValuesTool],
});

// Find the function call step
const fcStep = interaction.steps.find(s => s.type === 'function_call');
console.log(fcStep);

模型返回一个包含 type、name 和 arguments 的 function_call 步：

type='function_call'
name='set_light_values'
arguments={'color_temp': 'warm', 'brightness': 25}

第 3 步：执行函数

Python

# This will only work for SDK newer than 2.0.0
fc_step = next(s for s in interaction.steps if s.type == "function_call")

if fc_step.name == "set_light_values":
    result = set_light_values(**fc_step.arguments)
    print(f"Function execution result: {result}")

JavaScript

// This will only work for SDK newer than 2.0.0
const fcStep = interaction.steps.find(s => s.type === 'function_call');

let result;
if (fcStep.name === 'set_light_values') {
  result = setLightValues(fcStep.arguments.brightness, fcStep.arguments.color_temp);
  console.log(`Function execution result: ${JSON.stringify(result)}`);
}

第 4 步：将结果发送回模型

Python

# This will only work for SDK newer than 2.0.0
final_interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input=[
        {
            "type": "function_result",
            "name": fc_step.name,
            "call_id": fc_step.id,
            "result": [{"type": "text", "text": json.dumps(result)}],
        }
    ],
    tools=[set_light_values_declaration],
    previous_interaction_id=interaction.id,
)

print(final_interaction.steps[-1].content[0].text)

JavaScript

// This will only work for SDK newer than 2.0.0
const finalInteraction = await client.interactions.create({
  model: 'gemini-3-flash-preview',
  input: [{
    type: 'function_result',
    name: fcStep.name,
    call_id: fcStep.id,
    result: [{ type: 'text', text: JSON.stringify(result) }]
  }],
  tools: [setLightValuesTool],
  previous_interaction_id: interaction.id,
});

console.log(finalInteraction.steps.at(-1).content[0].text);

无状态函数调用

您还可以通过在客户端管理对话记录并设置 store=false，在无状态模式下使用函数调用。

在无状态模式下，您必须在每个后续请求的 input 字段中传递完整的对话历史记录。此记录必须包含： 1. 初始 user_input 步长。 2. 第 1 轮中返回的所有模型生成的步骤（包括 thought 和 function_call 步骤），与接收到的完全相同。 3. 包含已执行函数的输出的 function_result 步骤。

Python

# This will only work for SDK newer than 2.0.0
from google import genai
import json

client = genai.Client()

# Initialize history with Turn 1 input
history = [
    {
        "type": "user_input",
        "content": [{"type": "text", "text": "Turn the lights down to a romantic level"}]
    }
]

# Turn 1: Call model with tools and store=False
interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    store=False,
    input=history,
    tools=[set_light_values_declaration],
)

# Append all model-generated steps (including thoughts and function_calls)
for step in interaction.steps:
    history.append(step.model_dump())

# Find the function call step to execute it
fc_step = next(s for s in interaction.steps if s.type == "function_call")
if fc_step.name == "set_light_values":
    result = set_light_values(**fc_step.arguments)

# Append the function result as a step
history.append({
    "type": "function_result",
    "name": fc_step.name,
    "call_id": fc_step.id,
    "result": [{"type": "text", "text": json.dumps(result)}],
})

# Turn 2: Send the full history to get the final response
final_interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    store=False,
    input=history,
    tools=[set_light_values_declaration],
)

print(final_interaction.steps[-1].content[0].text)

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from "@google/genai";

const client = new GoogleGenAI({});

async function main() {
  // Initialize history with Turn 1 input
  const history = [
    {
      type: "user_input",
      content: [{ type: "text", text: "Turn the lights down to a romantic level" }]
    }
  ];

  // Turn 1: Call model with tools and store: false
  const interaction = await client.interactions.create({
    model: "gemini-3-flash-preview",
    store: false,
    input: history,
    tools: [setLightValuesTool],
  });

  // Append all model-generated steps
  history.push(...interaction.steps);

  // Find and execute function
  const fcStep = interaction.steps.find(s => s.type === 'function_call');
  let result;
  if (fcStep.name === 'set_light_values') {
    result = setLightValues(fcStep.arguments.brightness, fcStep.arguments.color_temp);
  }

  // Append function result step
  history.push({
    type: 'function_result',
    name: fcStep.name,
    call_id: fcStep.id,
    result: [{ type: 'text', text: JSON.stringify(result) }]
  });

  // Turn 2: Send full history
  const finalInteraction = await client.interactions.create({
    model: 'gemini-3-flash-preview',
    store: false,
    input: history,
    tools: [setLightValuesTool],
  });

  console.log(finalInteraction.steps.at(-1).content[0].text);
}

await main();

REST

# Turn 1: Send request with tools and store: false
# Specifies the API revision to avoid breaking changes when they become default
RESPONSE1=$(curl -s -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -H "Api-Revision: 2026-05-20" \
  -d '{
    "model": "gemini-3-flash-preview",
    "store": false,
    "input": [
      {
        "type": "user_input",
        "content": [{"type": "text", "text": "Turn the lights down to a romantic level"}]
      }
    ],
    "tools": [{
      "type": "function",
      "name": "set_light_values",
      "description": "Sets the brightness and color temperature of a light.",
      "parameters": {
        "type": "object",
        "properties": {
          "brightness": {"type": "integer", "description": "Light level from 0 to 100"},
          "color_temp": {"type": "string", "enum": ["daylight", "cool", "warm"]}
        },
        "required": ["brightness", "color_temp"]
      }
    }]
  }')

# Extract model steps (thought, function_call)
MODEL_STEPS=$(echo "$RESPONSE1" | jq '.steps')

# Extract function call details to execute
FC_NAME=$(echo "$RESPONSE1" | jq -r '.steps[] | select(.type=="function_call") | .name')
FC_ID=$(echo "$RESPONSE1" | jq -r '.steps[] | select(.type=="function_call") | .id')

# Assume local execution returns: {"brightness": 25, "colorTemperature": "warm"}
RESULT="{\"brightness\": 25, \"colorTemperature\": \"warm\"}"

# Reconstruct history for Turn 2
HISTORY=$(jq -n \
  --argjson first_input '[{"type": "user_input", "content": [{"type": "text", "text": "Turn the lights down to a romantic level"}]}]' \
  --argjson model_steps "$MODEL_STEPS" \
  --arg fc_name "$FC_NAME" \
  --arg fc_id "$FC_ID" \
  --arg result "$RESULT" \
  '$first_input + $model_steps + [{"type": "function_result", "name": $fc_name, "call_id": $fc_id, "result": [{"type": "text", "text": $result}]}]')

# Turn 2: Send the full history
# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -H "Api-Revision: 2026-05-20" \
  -d "{
    \"model\": \"gemini-3-flash-preview\",
    \"store\": false,
    \"input\": $HISTORY,
    \"tools\": [{
      \"type\": \"function\",
      \"name\": \"set_light_values\",
      \"description\": \"Sets the brightness and color temperature of a light.\",
      \"parameters\": {
        \"type\": \"object\",
        \"properties\": {
          \"brightness\": {\"type\": \"integer\"},
          \"color_temp\": {\"type\": \"string\"}
        },
        \"required\": [\"brightness\", \"color_temp\"]
      }
    }]
  }"

函数声明

函数声明作为工具传递，包含以下内容：

  • type（字符串）：对于自定义函数，必须为 "function"。
  • name（字符串）：唯一的函数名称（使用下划线或驼峰命名法）。
  • description（字符串）：对函数用途的清晰说明。
  • parameters（对象）：函数预期的输入参数。
    • type（字符串）：总体数据类型，例如 object。
    • properties（对象）：包含类型和说明的各个参数。
    • required（数组）：必需的参数名称。

使用思考模型进行函数调用

Gemini 3 和 2.5 系列模型使用内部“思考”流程来改进函数调用。 SDK 会自动为您处理意念签名。

并行函数调用

在多个函数相互独立时，一次调用多个函数：

Python

# This will only work for SDK newer than 2.0.0
power_disco_ball = {"type": "function", "name": "power_disco_ball", "description": "Powers the disco ball.",
    "parameters": {"type": "object", "properties": {"power": {"type": "boolean"}}, "required": ["power"]}}
start_music = {"type": "function", "name": "start_music", "description": "Play music.",
    "parameters": {"type": "object", "properties": {"energetic": {"type": "boolean"}, "loud": {"type": "boolean"}}, "required": ["energetic", "loud"]}}
dim_lights = {"type": "function", "name": "dim_lights", "description": "Dim the lights.",
    "parameters": {"type": "object", "properties": {"brightness": {"type": "number"}}, "required": ["brightness"]}}

client = genai.Client()

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input="Turn this place into a party!",
    tools=[power_disco_ball, start_music, dim_lights],
    generation_config={"tool_choice": "any"},
)

for step in interaction.steps:
    if step.type == "function_call":
        args = ", ".join(f"{key}={val}" for key, val in step.arguments.items())
        print(f"{step.name}({args})")

JavaScript

// This will only work for SDK newer than 2.0.0
const powerDiscoBall = { type: 'function', name: 'power_disco_ball', description: 'Powers the disco ball.',
  parameters: { type: 'object', properties: { power: { type: 'boolean' } }, required: ['power'] } };
const startMusic = { type: 'function', name: 'start_music', description: 'Play music.',
  parameters: { type: 'object', properties: { energetic: { type: 'boolean' }, loud: { type: 'boolean' } }, required: ['energetic', 'loud'] } };
const dimLights = { type: 'function', name: 'dim_lights', description: 'Dim the lights.',
  parameters: { type: 'object', properties: { brightness: { type: 'number' } }, required: ['brightness'] } };

const interaction = await client.interactions.create({
  model: 'gemini-3-flash-preview',
  input: 'Turn this place into a party!',
  tools: [powerDiscoBall, startMusic, dimLights],
  generation_config: { tool_choice: 'any' },
});

for (const step of interaction.steps) {
  if (step.type === 'function_call') {
    console.log(`${step.name}(${JSON.stringify(step.arguments)})`);
  }
}

组合式函数调用

将多个函数调用链接在一起，以处理复杂的请求（例如，先获取位置信息，然后获取该位置的天气）。

Python

# This will only work for SDK newer than 2.0.0
get_weather_forecast_declaration = {
    "type": "function",
    "name": "get_weather_forecast",
    "description": "Gets the current weather temperature for a given location.",
    "parameters": {
        "type": "object",
        "properties": {
            "location": {"type": "string", "description": "The location"},
        },
        "required": ["location"],
    },
}

set_thermostat_temperature_declaration = {
    "type": "function",
    "name": "set_thermostat_temperature",
    "description": "Sets the thermostat to a desired temperature.",
    "parameters": {
        "type": "object",
        "properties": {
            "temperature": {
                "type": "integer",
                "description": "The temperature in Celsius",
            },
        },
        "required": ["temperature"],
    },
}

client = genai.Client()

interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input="If it's warmer than 20°C in London, set the thermostat to 20°C, otherwise 18°C.",
    tools=[
        get_weather_forecast_declaration,
        set_thermostat_temperature_declaration,
    ],
)

for step in interaction.steps:
    if step.type == "function_call":
        print(f"Function to call: {step.name}")
        print(f"Arguments: {step.arguments}")
    elif hasattr(step, "content") and step.content:
         for part in step.content:
             if hasattr(part, "text"):
                 print(part.text)

函数调用模式

在 generation_config 中使用 tool_choice 控制模型使用工具的方式：

  • auto（默认值）：模型决定是调用函数还是直接回答。
  • any：模型会受到限制，始终预测函数调用。
  • none：禁止模型进行函数调用。

  • validated（预览版）：模型可确保函数架构符合要求。

Python

# This will only work for SDK newer than 2.0.0
generation_config = {
    "tool_choice": {
        "allowed_tools": {
            "mode": "any",
            "tools": ["get_current_temperature"]
        }
    }
}

JavaScript

// This will only work for SDK newer than 2.0.0
const generation_config = {
  tool_choice: {
    allowed_tools: {
      mode: 'any',
      tools: ['get_current_temperature']
    }
  }
};

REST

# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -H "Api-Revision: 2026-05-20" \
  -d '{
    "model": "gemini-3-flash-preview",
    "input": "What is the temperature in Boston?",
    "tools": [{
      "type": "function",
      "name": "get_current_temperature",
      "description": "Gets the current temperature for a given location.",
      "parameters": {
        "type": "object",
        "properties": {
          "location": {"type": "string"}
        },
        "required": ["location"]
      }
    }],
    "generation_config": {
      "tool_choice": {
        "allowed_tools": {
          "mode": "any",
          "tools": ["get_current_temperature"]
        }
      }
    }
  }'

多功能工具使用

您可以启用多个工具，在同一请求中将内置工具与函数调用相结合。Gemini 3 模型可在 Interactions 中将内置工具与函数调用功能结合使用。传递 previous_interaction_id 会自动循环使用内置工具上下文。

Python

# This will only work for SDK newer than 2.0.0
from google import genai
import json

client = genai.Client()

get_weather = {
    "type": "function",
    "name": "get_weather",
    "description": "Gets the weather for a requested city.",
    "parameters": {
        "type": "object",
        "properties": {
            "city": {
                "type": "string",
                "description": "The city and state, e.g. Utqiaġvik, Alaska",
            },
        },
        "required": ["city"],
    },
}

tools = [
    {"type": "google_search"},  # Built-in tool
    get_weather                 # Custom tool
]

# Turn 1: Initial request with both tools enabled
interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    input="What is the northernmost city in the United States? What's the weather like there today?",
    tools=tools
)

for step in interaction.steps:
    if step.type == "function_call":
        print(f"Function call: {step.name} (ID: {step.id})")
        # Execute your custom function locally
        result = {"response": "Very cold. 22 degrees Fahrenheit."}
        # Turn 2: Provide the function result back to the model.
        # Passing `previous_interaction_id` automatically circulates the
        # built-in Google Search context from Turn 1
        interaction_2 = client.interactions.create(
            model="gemini-3-flash-preview",
            previous_interaction_id=interaction.id,
            tools=tools,
            input=[{
                "type": "function_result",
                "name": step.name,
                "call_id": step.id,
                "result": [{"type": "text", "text": json.dumps(result)}]
            }]
        )

        print(interaction_2.steps[-1].content[0].text)

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from '@google/genai';

const client = new GoogleGenAI({});

const weatherTool = {
    type: 'function',
    name: 'get_weather',
    description: 'Gets the weather for a given location.',
    parameters: {
        type: 'object',
        properties: {
            location: { type: 'string', description: 'The city and state, e.g. San Francisco, CA' }
        },
        required: ['location']
    }
};

const tools = [
    {type: 'google_search'}, // Built-in tool
    weatherTool              // Custom tool
];

// Turn 1: Initial request with both tools enabled
let interaction = await client.interactions.create({
    model: 'gemini-3-flash-preview',
    input: "What is the northernmost city in the United States? What's the weather like there today?",
    tools: tools
});

for (const step of interaction.steps) {
    if (step.type === 'function_call') {
        console.log(`Function call: ${step.name} (ID: ${step.id})`);
        // Execute your custom function locally
        const result = {response: "Very cold. 22 degrees Fahrenheit."};
        // Turn 2: Provide the function result back to the model.
        const interaction_2 = await client.interactions.create({
            model: 'gemini-3-flash-preview',
            previous_interaction_id: interaction.id,
            tools: tools,
            input: [{
                type: 'function_result',
                name: step.name,
                call_id: step.id,
                result: [{ type: 'text', text: JSON.stringify(result) }]
            }]
        });

        console.log(interaction_2.steps.at(-1).content[0].text);
    }
}

多模态函数响应

对于 Gemini 3 系列模型，您可以在发送给模型的函数响应部分中添加多模态内容。模型可以在下一轮对话中处理此多模态内容，从而生成更明智的回答。

如需在函数响应中包含多模态数据，请将其作为 function_result 步骤的 result 字段中的一个或多个内容块。每个禁播内容都必须指定其 type（例如 "text"、"image"）。

以下示例展示了如何在互动中将包含图片数据的功能响应发送回模型：

Python

# This will only work for SDK newer than 2.0.0
import base64
from google import genai
import requests

client = genai.Client()

# Find the function call step
tool_call = next(s for s in interaction.steps if s.type == "function_call")

# Execute your tool to get image bytes
image_path = "https://goo.gle/instrument-img"
image_bytes = requests.get(image_path).content

base64_image_data = base64.b64encode(image_bytes).decode("utf-8")

final_interaction = client.interactions.create(
    model="gemini-3-flash-preview",
    previous_interaction_id=interaction.id,
    input=[
        {
            "type": "function_result",
            "name": tool_call.name,
            "call_id": tool_call.id,
            "result": [
                {"type": "text", "text": "instrument.jpg"},
                {
                    "type": "image",
                    "mime_type": "image/jpeg",
                    "data": base64_image_data,
                },
            ],
        }
    ],
)

print(final_interaction.steps[-1].content[0].text)

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

// Find the function call step
const toolCall = interaction.steps.find(s => s.type === 'function_call');

// Execute your tool to get image bytes and convert to base64
// (Implementation depends on your environment)
const base64ImageData = "BASE64_IMAGE_DATA";

const finalInteraction = await ai.interactions.create({
    model: 'gemini-3-flash-preview',
    previous_interaction_id: interaction.id,
    input: [{
        type: 'function_result',
        name: toolCall.name,
        call_id: toolCall.id,
        result: [
            { type: 'text', text: 'instrument.jpg' },
            {
                type: 'image',
                mime_type: 'image/jpeg',
                data: base64ImageData,
            }
        ]
    }]
});

console.log(finalInteraction.steps.at(-1).content[0].text);

REST

# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -H "Api-Revision: 2026-05-20" \
  -d '{
    "model": "gemini-3-flash-preview",
    "previous_interaction_id": "INTERACTION_ID",
    "input": [
      {
        "type": "function_result",
        "name": "get_image",
        "call_id": "call_123",
        "result": [
          {"type": "text", "text": "instrument.jpg"},
          {
            "type": "image",
            "mime_type": "image/jpeg",
            "data": "BASE64_IMAGE_DATA"
          }
        ]
      }
    ]
  }'

使用结构化输出进行函数调用

对于 Gemini 3 系列模型，您可以将函数调用与结构化输出相结合，以便获得格式一致的回答。

远程 MCP（模型上下文协议）

Interactions API 支持连接到远程 MCP 服务器，以便模型访问外部工具和服务。您可以在工具配置中提供服务器 name 和 url。

使用远程 MCP 时，请注意以下限制：

  • 服务器类型：远程 MCP 仅适用于可流式传输的 HTTP 服务器。不支持 SSE（服务器发送的事件）服务器。
  • 模型支持：远程 MCP 目前无法与 Gemini 3 模型搭配使用。我们很快就会支持 Gemini 3。
  • 命名：MCP 服务器名称不应包含 - 字符。请改用 snake_case 服务器名称。
字段 类型 是否必需 说明
type string 是 必须为 "mcp_server"。
name string 否 MCP 服务器的显示名称。
url string 否 MCP 服务器端点的完整网址。
headers object 否 作为 HTTP 标头随每个请求一起发送到服务器的键值对（例如身份验证令牌）。
allowed_tools array 否 限制智能体可调用的服务器工具。

示例

Python

# This will only work for SDK newer than 2.0.0
from google import genai

client = genai.Client()

interaction = client.interactions.create(
    model="gemini-2.5-flash",
    input="Check the status of my last server deployment.",
    tools=[
        {
            "type": "mcp_server",
            "name": "Deployment Tracker",
            "url": "https://mcp.example.com/mcp",
            "headers": {"Authorization": "Bearer my-token"},
        }
    ]
)

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from '@google/genai';

const client = new GoogleGenAI({});

const interaction = await client.interactions.create({
    model: 'gemini-2.5-flash',
    input: 'Check the status of my last server deployment.',
    tools: [
        {
            type: 'mcp_server',
            name: 'Deployment Tracker',
            url: 'https://mcp.example.com/mcp',
            headers: { Authorization: 'Bearer my-token' }
        }
    ]
});

REST

# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions" \
  -H "Content-Type: application/json" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H "Api-Revision: 2026-05-20" \
-d '{
    "model": "gemini-2.5-flash",
    "input": "Check the status of my last server deployment.",
    "tools": [
        {
            "type": "mcp_server",
            "name": "Deployment Tracker",
            "url": "https://mcp.example.com/mcp",
            "headers": {"Authorization": "Bearer my-token"}
        }
    ]
}'

对工具调用进行流式传输

将工具与流式传输搭配使用时，模型会在流中生成一系列 step.delta 事件作为函数调用。可以使用 arguments 将工具实参作为部分实参进行流式传输。您必须先汇总这些增量，以重建完整的工具调用，然后才能执行它们。

Python

# This will only work for SDK newer than 2.0.0
import json
from google import genai

client = genai.Client()

weather_tool = {
    "type": "function",
    "name": "get_weather",
    "description": "Gets the weather for a given location.",
    "parameters": {
        "type": "object",
        "properties": {
            "location": {"type": "string", "description": "The city and state"}
        },
        "required": ["location"]
    }
}

stream = client.interactions.create(
    model="gemini-3-flash-preview",
    input="What is the weather in Paris?",
    tools=[weather_tool],
    stream=True
)

current_calls = {}
tool_calls = []

for event in stream:
    if event.event_type == "step.start":
        if event.step.type == "function_call":
            current_calls[event.index] = {
                "id": event.step.id,
                "name": event.step.name,
                "arguments": ""
            }
            # Handle arguments provided in step.start
            if hasattr(event.step, "arguments") and event.step.arguments:
                if isinstance(event.step.arguments, dict):
                    current_calls[event.index]["arguments"] = json.dumps(event.step.arguments)
                else:
                    current_calls[event.index]["arguments"] = event.step.arguments
    elif event.event_type == "step.delta":
        if event.delta.type == "arguments":
            if event.index in current_calls:
                current_calls[event.index]["arguments"] += event.delta.partial_arguments
        elif event.delta.type == "text":
            print(event.delta.text, end="", flush=True)

    elif event.event_type == "interaction.completed":
        for index, call in current_calls.items():
            args = call["arguments"]
            if args:
                args = json.loads(args)
            else:
                args = {}

            tool_calls.append({
                "type": "function_call",
                "id": call["id"],
                "name": call["name"],
                "arguments": args
            })

        print(f"\nFinal tool calls ready to execute:")
        print(json.dumps(tool_calls, indent=2))

JavaScript

// This will only work for SDK newer than 2.0.0
import { GoogleGenAI } from '@google/genai';

const client = new GoogleGenAI({});

const weatherTool = {
    type: 'function',
    name: 'get_weather',
    description: 'Gets the weather for a given location.',
    parameters: {
        type: 'object',
        properties: {
            location: { type: 'string', description: 'The city and state' }
        },
        required: ['location']
    }
};

const stream = await client.interactions.create({
    model: 'gemini-3-flash-preview',
    input: 'What is the weather in Paris?',
    tools: [weatherTool],
    stream: true,
});

const currentCalls = new Map();
let toolCalls = [];

for await (const event of stream) {
    const evType = event.event_type;
    if (evType === 'step.start') {
        if (event.step.type === 'function_call') {
            currentCalls.set(event.index, {
                id: event.step.id,
                name: event.step.name,
                arguments: ''
            });
            // Handle arguments provided in step.start
            if (event.step.arguments) {
                if (typeof event.step.arguments === 'object') {
                    currentCalls.get(event.index).arguments = JSON.stringify(event.step.arguments);
                } else {
                    currentCalls.get(event.index).arguments = event.step.arguments;
                }
            }
        }
    } else if (evType === 'step.delta') {
        if (event.delta.type === 'arguments') {
            if (currentCalls.has(event.index)) {
                currentCalls.get(event.index).arguments += event.delta.partial_arguments;
            }
        } else if (event.delta.type === 'text') {
            process.stdout.write(event.delta.text);
        }
    } else if (evType === 'interaction.completed' || evType === 'interaction.complete') {
        toolCalls = Array.from(currentCalls.values()).map(call => ({
            type: 'function_call',
            id: call.id,
            name: call.name,
            arguments: call.arguments ? JSON.parse(call.arguments) : {}
        }));
        console.log('\nFinal tool calls ready to execute:');
        console.log(JSON.stringify(toolCalls, null, 2));
    }
}

REST

# Specifies the API revision to avoid breaking changes when they become default
curl -X POST "https://generativelanguage.googleapis.com/v1beta/interactions?alt=sse" \
  -H "Content-Type: application/json" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H "Api-Revision: 2026-05-20" \
-d '{
    "model": "gemini-3-flash-preview",
    "input": "What is the weather in Paris?",
    "tools": [{
        "type": "function",
        "name": "get_weather",
        "description": "Gets the weather for a given location.",
        "parameters": {
            "type": "object",
            "properties": {
                "location": {"type": "string", "description": "The city and state"}
            },
            "required": ["location"]
        }
    }],
    "stream": true
}'

最佳做法

  • 函数和参数说明：应清晰而具体。
  • 命名：使用不含空格或特殊字符的描述性名称。
  • 强类型：使用特定类型（整数、字符串、枚举）。
  • 工具选择：将有效工具数量保持在 10-20 个以内。
  • 提示工程：提供背景信息和指令。
  • 验证：在执行函数调用之前进行验证。
  • 错误处理：实现强大的错误处理机制。
  • 安全性：为外部 API 使用适当的身份验证。

注释和限制

  • 仅支持 OpenAPI 架构的子集。
  • 对于 any 模式，API 可能会拒绝非常大或深度嵌套的架构。
  • Python 中支持的形参类型有限。