文本生成

Gemini API 可以根据文本、图片、视频和音频输入生成文本输出。

下面是一个基本示例：

Python

from google import genai

client = genai.Client()

response = client.models.generate_content(
    model="gemini-3.5-flash",
    contents="How does AI work?"
)
print(response.text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const response = await ai.models.generateContent({
    model: "gemini-3.5-flash",
    contents: "How does AI work?",
  });
  console.log(response.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  result, _ := client.Models.GenerateContent(
      ctx,
      "gemini-3.5-flash",
      genai.Text("Explain how AI works in a few words"),
      nil,
  )

  fmt.Println(result.Text())
}

Java

import com.google.genai.Client;
import com.google.genai.types.GenerateContentResponse;

public class GenerateContentWithTextInput {
  public static void main(String[] args) {

    Client client = new Client();

    GenerateContentResponse response =
        client.models.generateContent("gemini-3.5-flash", "How does AI work?", null);

    System.out.println(response.text());
  }
}

REST

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "parts": [
          {
            "text": "How does AI work?"
          }
        ]
      }
    ]
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const payload = {
    contents: [
      {
        parts: [
          { text: 'How AI does work?' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

与 Gemini 一起思考

Gemini 模型通常默认启用“思考”功能，以便模型在回答请求之前进行推理。

每种模型都支持不同的思考配置，让您可以控制费用、延迟时间和智能程度。如需了解详情，请参阅思维指南。

Python

from google import genai
from google.genai import types

client = genai.Client()

response = client.models.generate_content(
    model="gemini-3.5-flash",
    contents="How does AI work?",
    config=types.GenerateContentConfig(
        thinking_config=types.ThinkingConfig(thinking_level="low")
    ),
)
print(response.text)

JavaScript

import { GoogleGenAI, ThinkingLevel } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const response = await ai.models.generateContent({
    model: "gemini-3.5-flash",
    contents: "How does AI work?",
    config: {
      thinkingConfig: {
        thinkingLevel: ThinkingLevel.LOW,
      },
    }
  });
  console.log(response.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  thinkingLevelVal := "low"

  result, _ := client.Models.GenerateContent(
      ctx,
      "gemini-3.5-flash",
      genai.Text("How does AI work?"),
      &genai.GenerateContentConfig{
        ThinkingConfig: &genai.ThinkingConfig{
            ThinkingLevel: &thinkingLevelVal,
        },
      }
  )

  fmt.Println(result.Text())
}

Java

import com.google.genai.Client;
import com.google.genai.types.GenerateContentConfig;
import com.google.genai.types.GenerateContentResponse;
import com.google.genai.types.ThinkingConfig;
import com.google.genai.types.ThinkingLevel;

public class GenerateContentWithThinkingConfig {
  public static void main(String[] args) {

    Client client = new Client();

    GenerateContentConfig config =
        GenerateContentConfig.builder()
            .thinkingConfig(ThinkingConfig.builder().thinkingLevel(new ThinkingLevel("low")))
            .build();

    GenerateContentResponse response =
        client.models.generateContent("gemini-3.5-flash", "How does AI work?", config);

    System.out.println(response.text());
  }
}

REST

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "parts": [
          {
            "text": "How does AI work?"
          }
        ]
      }
    ],
    "generationConfig": {
      "thinkingConfig": {
        "thinkingLevel": "low"
      }
    }
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const payload = {
    contents: [
      {
        parts: [
          { text: 'How AI does work?' },
        ],
      },
    ],
    generationConfig: {
      thinkingConfig: {
        thinkingLevel: 'low'
      }
    }
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

系统指令和其他配置

您可以使用系统指令来引导 Gemini 模型的行为。为此，请传递一个 GenerateContentConfig 对象。

Python

from google import genai
from google.genai import types

client = genai.Client()

response = client.models.generate_content(
    model="gemini-3.5-flash",
    config=types.GenerateContentConfig(
        system_instruction="You are a cat. Your name is Neko."),
    contents="Hello there"
)

print(response.text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const response = await ai.models.generateContent({
    model: "gemini-3.5-flash",
    contents: "Hello there",
    config: {
      systemInstruction: "You are a cat. Your name is Neko.",
    },
  });
  console.log(response.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  config := &genai.GenerateContentConfig{
      SystemInstruction: genai.NewContentFromText("You are a cat. Your name is Neko.", genai.RoleUser),
  }

  result, _ := client.Models.GenerateContent(
      ctx,
      "gemini-3.5-flash",
      genai.Text("Hello there"),
      config,
  )

  fmt.Println(result.Text())
}

Java

import com.google.genai.Client;
import com.google.genai.types.Content;
import com.google.genai.types.GenerateContentConfig;
import com.google.genai.types.GenerateContentResponse;
import com.google.genai.types.Part;

public class GenerateContentWithSystemInstruction {
  public static void main(String[] args) {

    Client client = new Client();

    GenerateContentConfig config =
        GenerateContentConfig.builder()
            .systemInstruction(
                Content.fromParts(Part.fromText("You are a cat. Your name is Neko.")))
            .build();

    GenerateContentResponse response =
        client.models.generateContent("gemini-3.5-flash", "Hello there", config);

    System.out.println(response.text());
  }
}

REST

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "system_instruction": {
      "parts": [
        {
          "text": "You are a cat. Your name is Neko."
        }
      ]
    },
    "contents": [
      {
        "parts": [
          {
            "text": "Hello there"
          }
        ]
      }
    ]
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const systemInstruction = {
    parts: [{
      text: 'You are a cat. Your name is Neko.'
    }]
  };

  const payload = {
    systemInstruction,
    contents: [
      {
        parts: [
          { text: 'Hello there' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

您还可以使用 GenerateContentConfig 对象替换默认生成参数，例如 max_output_tokens。

Python

from google import genai
from google.genai import types

client = genai.Client()

response = client.models.generate_content(
    model="gemini-3.5-flash",
    contents=["Explain how AI works"],
    config=types.GenerateContentConfig(
        max_output_tokens=1000
    )
)
print(response.text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const response = await ai.models.generateContent({
    model: "gemini-3.5-flash",
    contents: "Explain how AI works",
    config: {
      maxOutputTokens: 1000,
    },
  });
  console.log(response.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "log"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  config := &genai.GenerateContentConfig{
    MaxOutputTokens:   1000,
    ResponseMIMEType:  "application/json",
  }

  result, _ := client.Models.GenerateContent(
    ctx,
    "gemini-3.5-flash",
    genai.Text("What is the average size of a swallow?"),
    config,
  )

  fmt.Println(result.Text())
}

Java

import com.google.genai.Client;
import com.google.genai.types.GenerateContentConfig;
import com.google.genai.types.GenerateContentResponse;

public class GenerateContentWithConfig {
  public static void main(String[] args) {

    Client client = new Client();

    GenerateContentConfig config = GenerateContentConfig.builder().maxOutputTokens(1000).build();

    GenerateContentResponse response =
        client.models.generateContent("gemini-3.5-flash", "Explain how AI works", config);

    System.out.println(response.text());
  }
}

REST

curl https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "parts": [
          {
            "text": "Explain how AI works"
          }
        ]
      }
    ],
    "generationConfig": {
      "stopSequences": [
        "Title"
      ],
      "maxOutputTokens": 1000
    }
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const generationConfig = {
    maxOutputTokens: 1000,
    responseFormat: { text: { mimeType: "text/plain" } },
  };

  const payload = {
    generationConfig,
    contents: [
      {
        parts: [
          { text: 'Explain how AI works in a few words' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

如需查看可配置参数及其说明的完整列表，请参阅 API 参考文档中的 GenerateContentConfig。

多模态输入

Gemini API 支持多模态输入，让您可以将文本与媒体文件相结合。以下示例演示了如何提供图片：

Python

from PIL import Image
from google import genai

client = genai.Client()

image = Image.open("/path/to/organ.png")
response = client.models.generate_content(
    model="gemini-3.5-flash",
    contents=[image, "Tell me about this instrument"]
)
print(response.text)

JavaScript

import {
  GoogleGenAI,
  createUserContent,
  createPartFromUri,
} from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const image = await ai.files.upload({
    file: "/path/to/organ.png",
  });
  const response = await ai.models.generateContent({
    model: "gemini-3.5-flash",
    contents: [
      createUserContent([
        "Tell me about this instrument",
        createPartFromUri(image.uri, image.mimeType),
      ]),
    ],
  });
  console.log(response.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  imagePath := "/path/to/organ.jpg"
  imgData, _ := os.ReadFile(imagePath)

  parts := []*genai.Part{
      genai.NewPartFromText("Tell me about this instrument"),
      &genai.Part{
          InlineData: &genai.Blob{
              MIMEType: "image/jpeg",
              Data:     imgData,
          },
      },
  }

  contents := []*genai.Content{
      genai.NewContentFromParts(parts, genai.RoleUser),
  }

  result, _ := client.Models.GenerateContent(
      ctx,
      "gemini-3.5-flash",
      contents,
      nil,
  )

  fmt.Println(result.Text())
}

Java

import com.google.genai.Client;
import com.google.genai.Content;
import com.google.genai.types.GenerateContentResponse;
import com.google.genai.types.Part;

public class GenerateContentWithMultiModalInputs {
  public static void main(String[] args) {

    Client client = new Client();

    Content content =
      Content.fromParts(
          Part.fromText("Tell me about this instrument"),
          Part.fromUri("/path/to/organ.jpg", "image/jpeg"));

    GenerateContentResponse response =
        client.models.generateContent("gemini-3.5-flash", content, null);

    System.out.println(response.text());
  }
}

REST

# Use a temporary file to hold the base64 encoded image data
TEMP_B64=$(mktemp)
trap 'rm -f "$TEMP_B64"' EXIT
base64 $B64FLAGS $IMG_PATH > "$TEMP_B64"

# Use a temporary file to hold the JSON payload
TEMP_JSON=$(mktemp)
trap 'rm -f "$TEMP_JSON"' EXIT

cat > "$TEMP_JSON" << EOF
{
  "contents": [
    {
      "parts": [
        {
          "text": "Tell me about this instrument"
        },
        {
          "inline_data": {
            "mime_type": "image/jpeg",
            "data": "$(cat "$TEMP_B64")"
          }
        }
      ]
    }
  ]
}
EOF

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d "@$TEMP_JSON"

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const imageUrl = 'https://example.com/image.jpg';
  const image = getImageData(imageUrl);
  const payload = {
    contents: [
      {
        parts: [
          { image },
          { text: 'Tell me about this instrument' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

function getImageData(url) {
  const blob = UrlFetchApp.fetch(url).getBlob();

  return {
    mimeType: blob.getContentType(),
    data: Utilities.base64Encode(blob.getBytes())
  };
}

如需了解提供图片的其他方法和更高级的图片处理功能，请参阅我们的图片理解指南。 该 API 还支持文档、视频和音频输入和理解。

流式响应

默认情况下，模型仅在整个生成过程完成后才返回回答。

为了获得更流畅的互动体验，请使用流式传输来逐步接收 GenerateContentResponse 实例（在生成时）。

Python

from google import genai

client = genai.Client()

response = client.models.generate_content_stream(
    model="gemini-3.5-flash",
    contents=["Explain how AI works"]
)
for chunk in response:
    print(chunk.text, end="")

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const response = await ai.models.generateContentStream({
    model: "gemini-3.5-flash",
    contents: "Explain how AI works",
  });

  for await (const chunk of response) {
    console.log(chunk.text);
  }
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  stream := client.Models.GenerateContentStream(
      ctx,
      "gemini-3.5-flash",
      genai.Text("Write a story about a magic backpack."),
      nil,
  )

  for chunk, _ := range stream {
      part := chunk.Candidates[0].Content.Parts[0]
      fmt.Print(part.Text)
  }
}

Java

import com.google.genai.Client;
import com.google.genai.ResponseStream;
import com.google.genai.types.GenerateContentResponse;

public class GenerateContentStream {
  public static void main(String[] args) {

    Client client = new Client();

    ResponseStream<GenerateContentResponse> responseStream =
      client.models.generateContentStream(
          "gemini-3.5-flash", "Write a story about a magic backpack.", null);

    for (GenerateContentResponse res : responseStream) {
      System.out.print(res.text());
    }

    // To save resources and avoid connection leaks, it is recommended to close the response
    // stream after consumption (or using try block to get the response stream).
    responseStream.close();
  }
}

REST

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:streamGenerateContent?alt=sse" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  --no-buffer \
  -d '{
    "contents": [
      {
        "parts": [
          {
            "text": "Explain how AI works"
          }
        ]
      }
    ]
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const payload = {
    contents: [
      {
        parts: [
          { text: 'Explain how AI works' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:streamGenerateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

多轮对话（聊天）

我们的 SDK 提供相应功能，可将多轮提示和回答收集到聊天中，让您轻松跟踪对话历史记录。

Python

from google import genai

client = genai.Client()
chat = client.chats.create(model="gemini-3.5-flash")

response = chat.send_message("I have 2 dogs in my house.")
print(response.text)

response = chat.send_message("How many paws are in my house?")
print(response.text)

for message in chat.get_history():
    print(f'role - {message.role}',end=": ")
    print(message.parts[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const chat = ai.chats.create({
    model: "gemini-3.5-flash",
    history: [
      {
        role: "user",
        parts: [{ text: "Hello" }],
      },
      {
        role: "model",
        parts: [{ text: "Great to meet you. What would you like to know?" }],
      },
    ],
  });

  const response1 = await chat.sendMessage({
    message: "I have 2 dogs in my house.",
  });
  console.log("Chat response 1:", response1.text);

  const response2 = await chat.sendMessage({
    message: "How many paws are in my house?",
  });
  console.log("Chat response 2:", response2.text);
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  history := []*genai.Content{
      genai.NewContentFromText("Hi nice to meet you! I have 2 dogs in my house.", genai.RoleUser),
      genai.NewContentFromText("Great to meet you. What would you like to know?", genai.RoleModel),
  }

  chat, _ := client.Chats.Create(ctx, "gemini-3.5-flash", nil, history)
  res, _ := chat.SendMessage(ctx, genai.Part{Text: "How many paws are in my house?"})

  if len(res.Candidates) > 0 {
      fmt.Println(res.Candidates[0].Content.Parts[0].Text)
  }
}

Java

import com.google.genai.Chat;
import com.google.genai.Client;
import com.google.genai.types.Content;
import com.google.genai.types.GenerateContentResponse;

public class MultiTurnConversation {
  public static void main(String[] args) {

    Client client = new Client();
    Chat chatSession = client.chats.create("gemini-3.5-flash");

    GenerateContentResponse response =
        chatSession.sendMessage("I have 2 dogs in my house.");
    System.out.println("First response: " + response.text());

    response = chatSession.sendMessage("How many paws are in my house?");
    System.out.println("Second response: " + response.text());

    // Get the history of the chat session.
    // Passing 'true' to getHistory() returns the curated history, which excludes
    // empty or invalid parts.
    // Passing 'false' here would return the comprehensive history, including
    // empty or invalid parts.
    ImmutableList<Content> history = chatSession.getHistory(true);
    System.out.println("History: " + history);
  }
}

REST

curl https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "role": "user",
        "parts": [
          {
            "text": "Hello"
          }
        ]
      },
      {
        "role": "model",
        "parts": [
          {
            "text": "Great to meet you. What would you like to know?"
          }
        ]
      },
      {
        "role": "user",
        "parts": [
          {
            "text": "I have two dogs in my house. How many paws are in my house?"
          }
        ]
      }
    ]
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const payload = {
    contents: [
      {
        role: 'user',
        parts: [
          { text: 'Hello' },
        ],
      },
      {
        role: 'model',
        parts: [
          { text: 'Great to meet you. What would you like to know?' },
        ],
      },
      {
        role: 'user',
        parts: [
          { text: 'I have two dogs in my house. How many paws are in my house?' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

流式传输还可用于多轮对话。

Python

from google import genai

client = genai.Client()
chat = client.chats.create(model="gemini-3.5-flash")

response = chat.send_message_stream("I have 2 dogs in my house.")
for chunk in response:
    print(chunk.text, end="")

response = chat.send_message_stream("How many paws are in my house?")
for chunk in response:
    print(chunk.text, end="")

for message in chat.get_history():
    print(f'role - {message.role}', end=": ")
    print(message.parts[0].text)

JavaScript

import { GoogleGenAI } from "@google/genai";

const ai = new GoogleGenAI({});

async function main() {
  const chat = ai.chats.create({
    model: "gemini-3.5-flash",
    history: [
      {
        role: "user",
        parts: [{ text: "Hello" }],
      },
      {
        role: "model",
        parts: [{ text: "Great to meet you. What would you like to know?" }],
      },
    ],
  });

  const stream1 = await chat.sendMessageStream({
    message: "I have 2 dogs in my house.",
  });
  for await (const chunk of stream1) {
    console.log(chunk.text);
    console.log("_".repeat(80));
  }

  const stream2 = await chat.sendMessageStream({
    message: "How many paws are in my house?",
  });
  for await (const chunk of stream2) {
    console.log(chunk.text);
    console.log("_".repeat(80));
  }
}

await main();

Go

package main

import (
  "context"
  "fmt"
  "os"
  "google.golang.org/genai"
)

func main() {

  ctx := context.Background()
  client, err := genai.NewClient(ctx, nil)
  if err != nil {
      log.Fatal(err)
  }

  history := []*genai.Content{
      genai.NewContentFromText("Hi nice to meet you! I have 2 dogs in my house.", genai.RoleUser),
      genai.NewContentFromText("Great to meet you. What would you like to know?", genai.RoleModel),
  }

  chat, _ := client.Chats.Create(ctx, "gemini-3.5-flash", nil, history)
  stream := chat.SendMessageStream(ctx, genai.Part{Text: "How many paws are in my house?"})

  for chunk, _ := range stream {
      part := chunk.Candidates[0].Content.Parts[0]
      fmt.Print(part.Text)
  }
}

Java

import com.google.genai.Chat;
import com.google.genai.Client;
import com.google.genai.ResponseStream;
import com.google.genai.types.GenerateContentResponse;

public class MultiTurnConversationWithStreaming {
  public static void main(String[] args) {

    Client client = new Client();
    Chat chatSession = client.chats.create("gemini-3.5-flash");

    ResponseStream<GenerateContentResponse> responseStream =
        chatSession.sendMessageStream("I have 2 dogs in my house.", null);

    for (GenerateContentResponse response : responseStream) {
      System.out.print(response.text());
    }

    responseStream = chatSession.sendMessageStream("How many paws are in my house?", null);

    for (GenerateContentResponse response : responseStream) {
      System.out.print(response.text());
    }

    // Get the history of the chat session. History is added after the stream
    // is consumed and includes the aggregated response from the stream.
    System.out.println("History: " + chatSession.getHistory(false));
  }
}

REST

curl https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:streamGenerateContent?alt=sse \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "role": "user",
        "parts": [
          {
            "text": "Hello"
          }
        ]
      },
      {
        "role": "model",
        "parts": [
          {
            "text": "Great to meet you. What would you like to know?"
          }
        ]
      },
      {
        "role": "user",
        "parts": [
          {
            "text": "I have two dogs in my house. How many paws are in my house?"
          }
        ]
      }
    ]
  }'

Apps 脚本

// See https://developers.google.com/apps-script/guides/properties
// for instructions on how to set the API key.
const apiKey = PropertiesService.getScriptProperties().getProperty('GEMINI_API_KEY');

function main() {
  const payload = {
    contents: [
      {
        role: 'user',
        parts: [
          { text: 'Hello' },
        ],
      },
      {
        role: 'model',
        parts: [
          { text: 'Great to meet you. What would you like to know?' },
        ],
      },
      {
        role: 'user',
        parts: [
          { text: 'I have two dogs in my house. How many paws are in my house?' },
        ],
      },
    ],
  };

  const url = 'https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:streamGenerateContent';
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'x-goog-api-key': apiKey,
    },
    payload: JSON.stringify(payload)
  };

  const response = UrlFetchApp.fetch(url, options);
  const data = JSON.parse(response);
  const content = data['candidates'][0]['content']['parts'][0]['text'];
  console.log(content);
}

撰写提示的技巧！

如需了解如何充分利用 Gemini，请参阅我们的提示工程指南。

后续步骤

内容生成

这是向模型发送提示的中心端点。有两个用于生成内容的端点，主要区别在于您接收响应的方式：

  • generateContent (REST)：接收请求，并在模型完成整个生成过程后提供单个回答。
  • streamGenerateContent (SSE)：接收完全相同的请求，但模型会以流式传输方式返回生成的回答块。这可为互动式应用提供更好的用户体验，因为您可以立即显示部分结果。

请求正文结构

请求正文是一个 JSON 对象，在标准模式和流式模式下完全相同，由几个核心对象构建而成：

  • Content 对象：表示对话中的单个回合。
  • Part 对象：Content 回合中的一段数据（例如文本或图片）。
  • inline_data (Blob)：用于存储原始媒体字节及其 MIME 类型的容器。

在最高层级，请求正文包含一个 contents 对象，该对象是一个 Content 对象列表，每个对象都表示对话中的一个轮次。在大多数情况下，对于基本文本生成，您将使用单个 Content 对象，但如果您想保留对话历史记录，可以使用多个 Content 对象。

以下示例展示了一个典型的 generateContent 请求正文：

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
          "role": "user",
          "parts": [
              // A list of Part objects goes here
          ]
      },
      {
          "role": "model",
          "parts": [
              // A list of Part objects goes here
          ]
      }
    ]
  }'

响应正文结构

无论是流式模式还是标准模式，响应正文都类似，但以下方面除外：

从总体上讲，响应正文包含一个 candidates 对象，该对象是一个 Candidate 对象列表。Candidate 对象包含一个 Content 对象，该对象具有从模型返回的生成的回答。

REST API 示例

多模态提示（文本和图片）

如需在提示中同时提供文本和图片，parts 数组应包含两个 Part 对象：一个用于文本，另一个用于图片 inline_data。

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
-H "x-goog-api-key: $GEMINI_API_KEY" \
-H 'Content-Type: application/json' \
-X POST \
-d '{
    "contents": [{
    "parts":[
        {
            "inline_data": {
            "mime_type":"image/jpeg",
            "data": "/9j/4AAQSkZJRgABAQ... (base64-encoded image)"
            }
        },
        {"text": "What is in this picture?"},
      ]
    }]
  }'

多轮对话（聊天）

如需构建多回合对话，您可以使用多个 Content 对象定义 contents 数组。API 会将整个历史记录用作下一个回答的上下文。每个 Content 对象的 role 应在 user 和 model 之间交替。

curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" \
  -H 'Content-Type: application/json' \
  -X POST \
  -d '{
    "contents": [
      {
        "role": "user",
        "parts": [
          { "text": "Hello." }
        ]
      },
      {
        "role": "model",
        "parts": [
          { "text": "Hello! How can I help you today?" }
        ]
      },
      {
        "role": "user",
        "parts": [
          { "text": "Please write a four-line poem about the ocean." }
        ]
      }
    ]
  }'

要点总结

  • Content 是信封：它是消息轮次的顶级容器，无论消息来自用户还是模型。
  • Part 支持多模态：在单个 Content 对象中使用多个 Part 对象来组合不同类型的数据（文本、图片、视频 URI 等）。
  • 选择数据方法：
    • 对于直接嵌入的小型媒体（例如大多数图片），请使用带有 inline_data 的 Part。
    • 对于较大的文件或您想在多个请求中重复使用的文件，请使用 File API 上传文件，并通过 file_data 部分引用该文件。
  • 管理对话历史记录：对于使用 REST API 的聊天应用，请通过为每个对话轮次附加 Content 对象来构建 contents 数组，并在 "user" 和 "model" 角色之间交替。如果您使用的是 SDK，请参阅 SDK 文档，了解管理对话记录的推荐方式。

响应示例

以下示例展示了这些组件如何针对不同类型的请求协同工作。

纯文本回答

默认文本回答由一个 candidates 数组组成，其中包含一个或多个 content 对象，这些对象包含模型的回答。

以下是标准回答的示例：

{
  "candidates": [
    {
      "content": {
        "parts": [
          {
            "text": "At its core, Artificial Intelligence works by learning from vast amounts of data ..."
          }
        ],
        "role": "model"
      },
      "finishReason": "STOP",
      "index": 1
    }
  ],
}

以下是一系列流式响应。每个响应都包含一个 responseId，用于将整个响应关联起来：

{
  "candidates": [
    {
      "content": {
        "parts": [
          {
            "text": "The image displays"
          }
        ],
        "role": "model"
      },
      "index": 0
    }
  ],
  "usageMetadata": {
    "promptTokenCount": ...
  },
  "modelVersion": "gemini-3.5-flash",
  "responseId": "mAitaLmkHPPlz7IPvtfUqQ4"
}

...

{
  "candidates": [
    {
      "content": {
        "parts": [
          {
            "text": " the following materials:\n\n*   **Wood:** The accordion and the violin are primarily"
          }
        ],
        "role": "model"
      },
      "index": 0
    }
  ],
  "usageMetadata": {
    "promptTokenCount": ...
  }
  "modelVersion": "gemini-3.5-flash",
  "responseId": "mAitaLmkHPPlz7IPvtfUqQ4"
}

Live API (BidiGenerateContent) WebSocket API

Live API 提供基于 WebSocket 的有状态 API，用于双向流式传输，以实现实时流式传输用例。您可以查看 Live API 指南和 Live API 参考文档，了解更多详情。

专业模型

除了 Gemini 模型系列之外，Gemini API 还提供 Imagen、Lyria 和嵌入模型等专用模型的端点。您可以在“模型”部分下查看这些指南。

平台 API

其余端点可实现其他功能，以便与目前所述的主要端点搭配使用。如需了解详情，请查看“指南”部分中的批量模式和 File API 主题。

后续步骤

如果您刚刚开始使用 Gemini API，请查看以下指南，这些指南将有助于您了解 Gemini API 编程模型：

您可能还想查看功能指南，其中介绍了不同的 Gemini API 功能并提供了代码示例：