Vertex AI SDK 移行ガイド

Vertex AI SDK の生成 AI モジュールは非推奨になり、2026 年 6 月 24 日以降は使用できなくなります。Google Gen AI SDK には Vertex AI SDK のすべての機能が含まれており、多くの追加機能をサポートしています。

この移行ガイドを使用して、Vertex AI SDK を使用する Python、Java、JavaScript、Go のコードを Google Gen AI SDK に変換します。

主な変更点

Vertex AI SDK の次の名前空間は非推奨フェーズに入っています。2026 年 6 月 24 日以降の SDK リリースには、これらのモジュールは含まれません。非推奨のモジュールとパッケージと同等の機能を備えた Google Gen AI SDK の同等の名前空間を使用します。

Vertex AI SDK 影響を受けるコード Google Gen AI SDK の置き換え
google-cloud-aiplatform 削除されたモジュール:
 google-genai
cloud.google.com/go/vertexai/genai 削除されたパッケージ:
 google.golang.org/genai
@google-cloud/vertexai 削除されたモジュール:
 @google/genai
com.google.cloud:google-cloud-vertexai 削除されたパッケージ:
 com.google.genai:google-genai

コードの移行

以降のセクションでは、Vertex AI SDK から Google Gen AI SDK に特定のコード スニペットを移行する方法について説明します。

インストール

Vertex AI SDK の依存関係を Google Gen AI SDK の依存関係に置き換えます。

変更前

Python

pip install -U -q "google-cloud-aiplatform"

Java

Gradle:

gradle:
  implementation 'com.google.cloud:google-cloud-vertexai:1.26.0'

maven:

  <dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-vertexai</artifactId>
    <version>1.26.0</version>
  </dependency>

JavaScript

npm install @google-cloud/vertexai

Go

go get cloud.google.com/go/vertexai/genai

変更後

Python

pip install -U -q "google-genai"

Java

gradle:

  implementation 'com.google.genai:google-genai:1.5.0'

maven:

  <dependency>
    <groupId>com.google.genai</groupId>
    <artifactId>google-genai</artifactId>
    <version>1.5.0</version>
  </dependency>

JavaScript

npm install @google/genai

Go

go get google.golang.org/genai

コンテキストのキャッシュ保存

コンテキスト キャッシュ保存では、類似するリクエストでよく使用されるモデル プロンプトの部分を保存して再利用します。Vertex AI SDK の実装を Google Gen AI SDK の依存関係に置き換えます。

変更前

Python

インポート

from google.cloud import aiplatform
import vertexai
import datetime

作成

vertexai.init(project=GOOGLE_CLOUD_PROJECT, location=GOOGLE_CLOUD_LOCATION)

cache_content = vertexai.caching.CachedContent.create(
  model_name=MODEL_NAME,
  system_instruction='Please answer my question formally',
  contents=['user content'],
  ttl=datetime.timedelta(days=1),
)

取得

vertexai.init(project=GOOGLE_CLOUD_PROJECT, location=GOOGLE_CLOUD_LOCATION)
cache_content = vertexai.caching.CachedContent.get(cached_content_name="projects/{project}/locations/{location}/cachedContents/{cached_content}")

削除

cache_content.delete()

更新

cache_content.update(ttl=datetime.timedelta(days=2))

リスト

cache_contents = vertexai.caching.CachedContent.list()

Java

コンテキスト キャッシュ保存は、Java Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

JavaScript

コンテキスト キャッシュは JavaScript Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

Go

インポート

package contextcaching

// [START generativeaionvertexai_gemini_create_context_cache]
import (
  "context"
  "fmt"
  "io"
  "time"

  "cloud.google.com/go/vertexai/genai"
)

作成

content := &genai.CachedContent{
  Model: modelName,
  SystemInstruction: &genai.Content{
    Parts: []genai.Part{genai.Text(systemInstruction)},
  },
  Expiration: genai.ExpireTimeOrTTL{TTL: 60 * time.Minute},
  Contents: []*genai.Content{
    {
      Role:  "user",
      Parts: []genai.Part{part1, part2},
    },
  },
}

result, err := client.CreateCachedContent(context, content)

取得

cachedContent, err := client.GetCachedContent(context, contentName)

削除

err = client.DeleteCachedContent(context, contentName)

更新

newExpireTime := cc.Expiration.ExpireTime.Add(15 * time.Minute)
ccUpdated := client.UpdateCachedContent(context, cc, &genai.CachedContentToUpdate{
        Expiration: &genai.ExpireTimeOrTTL{ExpireTime: newExpireTime},
})

リスト

iter, err := client.ListCachedContents(context, contentName)

変更後

Python

インポート

from google import genai
from google.genai.types import Content, CreateCachedContentConfig, HttpOptions, Part

作成

client = genai.Client(http_options=HttpOptions(api_version="v1"))

content_cache = client.caches.create(
    model="gemini-2.5-flash",
    config=CreateCachedContentConfig(
        contents=contents,
        system_instruction=system_instruction,
        display_name="example-cache",
        ttl="86400s",
    ),
)

取得

content_cache_list = client.caches.list()

# Access individual properties of a ContentCache object(s)
for content_cache in content_cache_list:
    print(f"Cache `{content_cache.name}` for model `{content_cache.model}`")
    print(f"Last updated at: {content_cache.update_time}")
    print(f"Expires at: {content_cache.expire_time}")

削除

client.caches.delete(name=cache_name)

更新

content_cache = client.caches.update(
    name=cache_name, config=UpdateCachedContentConfig(ttl="36000s")
)

リスト

cache_contents = client.caches.list(config={'page_size': 2})

Java

インポート

import com.google.genai.types.CachedContent;
import com.google.genai.types.Content;
import com.google.genai.types.CreateCachedContentConfig;
import com.google.genai.types.DeleteCachedContentResponse;
import com.google.genai.types.ListCachedContentsConfig;

作成

Content content =
  Content.fromParts(
    fetchPdfPart(
      "https://storage.googleapis.com/cloud-samples-data/generative-ai/pdf/2403.05530.pdf"));

CreateCachedContentConfig config =
  CreateCachedContentConfig.builder()
    .systemInstruction(Content.fromParts(Part.fromText("summarize the pdf")))
    .expireTime(Instant.now().plus(Duration.ofHours(1)))
    .contents(content)
    .build();

CachedContent cachedContent1 = client.caches.create("gemini-2.5-flash", config);

取得

CachedContent cachedContent2 = client.caches.get(cachedContent1.name().get(), null);
System.out.println("get cached content: " + cachedContent2);

削除

DeleteCachedContentResponse unused = client.caches.delete(cachedContent1.name().get(), null);
System.out.println("Deleted cached content: " + cachedContent1.name().get());

更新

CachedContent cachedContentUpdate =
    client.caches.update(
        cachedContent.name().get(),
        UpdateCachedContentConfig.builder().ttl(Duration.ofMinutes(10)).build());
System.out.println("Update cached content: " + cachedContentUpdate);

リスト

System.out.println("List cached contents resrouce names: ");
for (CachedContent cachedContent :
    client.caches.list(ListCachedContentsConfig.builder().pageSize(5).build())) {
  System.out.println(cachedContent.name().get());
}

JavaScript

インポート

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

作成

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const cachedContent1: Part = {
  fileData: {
    fileUri: 'gs://cloud-samples-data/generative-ai/pdf/2403.05530.pdf',
    mimeType: 'application/pdf',
  },
};

const cachedContent2: Part = {
  fileData: {
    fileUri: 'gs://cloud-samples-data/generative-ai/pdf/2312.11805v3.pdf',
    mimeType: 'application/pdf',
  },
};

const cache = await ai.caches.create({
  model: 'gemini-1.5-pro-002',
  config: {contents: [cachedContent1, cachedContent2]},
});

取得

const getResponse = await ai.caches.get({name: cacheName});

削除

await ai.caches.delete({name: cacheName});

更新

const updateResponse = await ai.caches.update({
  name: cacheName,
  config: {ttl: '86400s'},
});

リスト

const listResponse = await ai.caches.list();
let i = 1;
for await (const cachedContent of listResponse) {
  console.debug(`List response ${i++}: `, JSON.stringify(cachedContent));
}

Go

インポート

import (
  "context"
  "encoding/json"
  "fmt"
  "io"

  genai "google.golang.org/genai"
)

作成

cacheContents := []*genai.Content{
  {
    Parts: []*genai.Part{
      {FileData: &genai.FileData{
        FileURI:  "gs://cloud-samples-data/generative-ai/pdf/2312.11805v3.pdf",
        MIMEType: "application/pdf",
      }},
      {FileData: &genai.FileData{
        FileURI:  "gs://cloud-samples-data/generative-ai/pdf/2403.05530.pdf",
        MIMEType: "application/pdf",
      }},
    },
    Role: "user",
  },
}
config := &genai.CreateCachedContentConfig{
  Contents: cacheContents,
  SystemInstruction: &genai.Content{
    Parts: []*genai.Part{
      {Text: systemInstruction},
    },
  },
  DisplayName: "example-cache",
  TTL:         "86400s",
}

res, err := client.Caches.Create(ctx, modelName, config)

取得

cachedContent, err := client.GetCachedContent(ctx, contentName)

削除

_, err = client.Caches.Delete(ctx, result.Name, &genai.DeleteCachedContentConfig{})

更新

result, err = client.Caches.Update(ctx, result.Name, &genai.UpdateCachedContentConfig{
  ExpireTime: time.Now().Add(time.Hour),
})

リスト

// List the first page.
page, err := client.Caches.List(ctx, &genai.ListCachedContentsConfig{PageSize: 2})

// Continue to the next page.
page, err = page.Next(ctx)

// Resume the page iteration using the next page token.
page, err = client.Caches.List(ctx, &genai.ListCachedContentsConfig{PageSize: 2, PageToken: page.NextPageToken})

構成とシステム指示

構成では、モデルの動作を制御するパラメータを定義します。システム指示では、モデルのレスポンスを特定のペルソナ、スタイル、タスクに向けるためのガイドラインが提供されます。Vertex AI SDK の構成とシステム手順を、Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

model = generative_models.GenerativeModel(
  GEMINI_MODEL_NAME,
  system_instruction=[
    "Talk like a pirate.",
    "Don't use rude words.",
  ],
)
response = model.generate_content(
  contents="Why is sky blue?",
  generation_config=generative_models.GenerationConfig(
    temperature=0,
    top_p=0.95,
    top_k=20,
    candidate_count=1,
    max_output_tokens=100,
    stop_sequences=["STOP!"],
    response_logprobs=True,
    logprobs=3,
  ),
  safety_settings={
    generative_models.HarmCategory.HARM_CATEGORY_HATE_SPEECH: generative_models.HarmBlockThreshold.BLOCK_MEDIUM_AND_ABOVE,
    generative_models.HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT: generative_models.HarmBlockThreshold.BLOCK_ONLY_HIGH,
    generative_models.HarmCategory.HARM_CATEGORY_HARASSMENT: generative_models.HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    generative_models.HarmCategory.HARM_CATEGORY_SEXUALLY_EXPLICIT: generative_models.HarmBlockThreshold.BLOCK_NONE,
  },
)

Java

import com.google.cloud.vertexai.api.GenerationConfig;

GenerationConfig generationConfig =
  GenerationConfig.newBuilder().setMaxOutputTokens(50).build();

// Use the builder to instantialize the model with the configuration.
GenerativeModel model =
  new GenerativeModel.Builder()
    .setModelName("gemino-pro")
    .setVertexAi(vertexAi)
    .setGenerationConfig(generationConfig)
    .build();

JavaScript

const {VertexAI} = require('@google-cloud/vertexai');

const generativeModel = vertexAI.getGenerativeModel({
  model: 'gemini-2.5-flash',
  systemInstruction: {
    parts: [
      {text: 'You are a helpful language translator.'},
      {text: 'Your mission is to translate text in English to French.'},
    ],
  },
});

const textPart = {
  text: `
  User input: I like bagels.
  Answer:`,
};

const request = {
  contents: [{role: 'user', parts: [textPart]}],
};

const resp = await generativeModel.generateContent(request);
const contentResponse = await resp.response;
console.log(JSON.stringify(contentResponse));

Go

import (
  "context"
  "cloud.google.com/go/vertexai/genai"
)

model := client.GenerativeModel(modelName)

model.GenerationConfig = genai.GenerationConfig{
  TopP:            proto.Float32(1),
  TopK:            proto.Int32(32),
  Temperature:     proto.Float32(0.4),
  MaxOutputTokens: proto.Int32(2048),
}

systemInstruction := fmt.Sprintf("Your mission is to translate text from %xs to %s", sourceLanguageCode, targetLanguageCode)

model.SystemInstruction = &genai.Content{
  Role:  "user",
  Parts: []genai.Part{genai.Text(systemInstruction)},
}

変更後

Python

from google.genai import types

response = client.models.generate_content(
  model='gemini-2.5-flash',
  contents='high',
  config=types.GenerateContentConfig(
    system_instruction='I say high, you say low',
    max_output_tokens=3,
    temperature=0.3,
    response_logprobs=True,
    logprobs=3,
  ),
)

Java

GenerateContentConfig をインポートします。

import com.google.genai.types.GenerateContentConfig;

システム指示を作成します。

Content systemInstruction = Content.fromParts(Part.fromText("You are a history teacher."));

コンテンツ構成にシステム指示を追加します。

GenerateContentConfig config =
  GenerateContentConfig.builder()
    ...
    .systemInstruction(systemInstruction)
    .build();

完全な実装については、GenerateContentWithConfigs.java をご覧ください。

JavaScript

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

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});
const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents: 'high',
  config: {systemInstruction: 'I say high you say low.'},
});
console.debug(response.text);

await generateContentFromVertexAI().catch((e) =>
  console.error('got error', e),
);

Go

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

config := &genai.GenerateContentConfig{
  SystemInstruction: &genai.Content{
    Parts: []*genai.Part{
      {Text: "You're a language translator. Your mission is to translate text in English to French."},
    },
  },
}

resp, err := client.Models.GenerateContent(ctx, modelName, contents, config)

エンベディング

エンベディングは、テキスト、画像、動画の数値ベクトル表現であり、高次元空間で意味的または視覚的な意味と関係性を捉えます。Vertex AI SDK のエンベディング実装を、Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

model = vertexai.vision_models.MultiModalEmbeddingModel.from_pretrained("multimodalembedding@001")
image = Image.load_from_file("image.png")
video = Video.load_from_file("video.mp4")

embeddings = model.get_embeddings(
  # One of image, video or contextual_text is required.
  image=image,
  video=video,
  contextual_text="Hello world",
)
image_embedding = embeddings.image_embedding
video_embeddings = embeddings.video_embeddings
text_embedding = embeddings.text_embedding

Java

エンベディングは Java Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

JavaScript

エンベディングは JavaScript Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

Go

エンベディングは Go Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

変更後

Python

from google.genai.types import EmbedContentConfig

client = genai.Client()
response = client.models.embed_content(
  model="gemini-embedding-001",
  contents="How do I get a driver's license/learner's permit?",
  config=EmbedContentConfig(
    task_type="RETRIEVAL_DOCUMENT",  # Optional
    output_dimensionality=3072,  # Optional
    title="Driver's License",  # Optional
  ),
)

Java

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

EmbedContentResponse response =
    client.models.embedContent("text-embedding-005", "why is the sky blue?", null);

JavaScript

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

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const response = await ai.models.embedContent({
  model: 'text-embedding-005',
  contents: 'Hello world!',
});

console.debug(JSON.stringify(response));

await embedContentFromVertexAI().catch((e) =>
  console.error('got error', e),
);

Go

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

result, err := client.Models.EmbedContent(ctx, *model, genai.Text("What is your name?"), &genai.EmbedContentConfig{TaskType: "RETRIEVAL_QUERY"})
fmt.Printf("%#v\n", result.Embeddings[0])

fmt.Println("Embed content RETRIEVAL_DOCUMENT task type example.")
result, err = client.Models.EmbedContent(ctx, *model, genai.Text("What is your name?"), &genai.EmbedContentConfig{TaskType: "RETRIEVAL_DOCUMENT"})
fmt.Printf("%#v\n", result.Embeddings[0])

関数呼び出し

関数呼び出しにより、モデルは外部ツールや API を呼び出すタイミングを特定し、実行に必要な関数と引数を含む構造化データを生成できます。関数呼び出しの実装を Vertex AI SDK に置き換えます。次のコードは、Google Gen AI SDK を使用しています。

変更前

Python

get_current_weather_func = generative_models.FunctionDeclaration(
  name="get_current_weather",
  description="Get the current weather in a given location",
  parameters=_REQUEST_FUNCTION_PARAMETER_SCHEMA_STRUCT,
)

weather_tool = generative_models.Tool(
  function_declarations=[get_current_weather_func],
)

model = generative_models.GenerativeModel(
  GEMINI_MODEL_NAME,
  tools=[weather_tool],
)

chat = model.start_chat()

response1 = chat.send_message("What is the weather like in Boston?")
assert (
  response1.candidates[0].content.parts[0].function_call.name
  == "get_current_weather"
)
response2 = chat.send_message(
  generative_models.Part.from_function_response(
    name="get_current_weather",
    response={
      "content": {"weather": "super nice"},
    },
  ),
)
assert response2.text

Java

Tool tool =
    Tool.newBuilder()
        .addFunctionDeclarations(
          FunctionDeclarationMaker.fromJsonString(jsonString)
        )
        .build();

// Start a chat session from a model, with the use of the declared
// function.
GenerativeModel model =
    new GenerativeModel.Builder()
        .setModelName(MODEL_NAME)
        .setVertexAi(vertexAi)
        .setTools(Arrays.asList(tool))
        .build();
ChatSession chat = model.startChat();

System.out.println(String.format("Ask the question: %s", TEXT));
GenerateContentResponse response = chat.sendMessage(TEXT);

// Provide an answer to the model so that it knows what the result of a
// "function call" is.
Content content =
    ContentMaker.fromMultiModalData(
        PartMaker.fromFunctionResponse(
            "getCurrentWeather", Collections.singletonMap("currentWeather", "snowing")));
response = chat.sendMessage(content);

JavaScript

const {
  VertexAI,
  FunctionDeclarationSchemaType,
} = require('@google-cloud/vertexai');

const functionDeclarations = [
  {
    function_declarations: [
      {
        name: 'get_current_weather',
        description: 'get weather in a given location',
        parameters: {
          type: FunctionDeclarationSchemaType.OBJECT,
          properties: {
            location: {type: FunctionDeclarationSchemaType.STRING},
            unit: {
              type: FunctionDeclarationSchemaType.STRING,
              enum: ['celsius', 'fahrenheit'],
            },
          },
          required: ['location'],
        },
      },
    ],
  },
];

async function functionCallingBasic(
  projectId = 'PROJECT_ID',
  location = 'us-central1',
  model = 'gemini-2.5-flash'
) {
  // Initialize Vertex with your Cloud project and location
  const vertexAI = new VertexAI({project: projectId, location: location});

  // Instantiate the model
  const generativeModel = vertexAI.preview.getGenerativeModel({
    model: model,
  });

  const request = {
    contents: [
      {role: 'user', parts: [{text: 'What is the weather in Boston?'}]},
    ],
    tools: functionDeclarations,
  };
  const result = await generativeModel.generateContent(request);
  console.log(JSON.stringify(result.response.candidates[0].content));
}

Go

package functioncalling

import (
  "context"
  "encoding/json"
  "errors"
  "fmt"
  "io"

  "cloud.google.com/go/vertexai/genai"
)

funcName := "getCurrentWeather"
funcDecl := &genai.FunctionDeclaration{
  Name:        funcName,
  Description: "Get the current weather in a given location",
  Parameters: &genai.Schema{
    Type: genai.TypeObject,
    Properties: map[string]*genai.Schema{
      "location": {
        Type:        genai.TypeString,
        Description: "location",
      },
    },
    Required: []string{"location"},
  },
}

// Add the weather function to our model toolbox.
model.Tools = []*genai.Tool{
  {
    FunctionDeclarations: []*genai.FunctionDeclaration{funcDecl},
  },
}

prompt := genai.Text("What's the weather like in Boston?")
resp, err := model.GenerateContent(ctx, prompt)

if len(resp.Candidates) == 0 {
  return errors.New("got empty response from model")
} else if len(resp.Candidates[0].FunctionCalls()) == 0 {
  return errors.New("got no function call suggestions from model")
}

funcResp := &genai.FunctionResponse{
  Name: funcName,
  Response: map[string]any{
    "content": mockAPIResp,
  },
}

// Return the API response to the model allowing it to complete its response.
resp, err = model.GenerateContent(ctx, prompt, funcResp)
if err != nil {
  return fmt.Errorf("failed to generate content: %w", err)
}
if len(resp.Candidates) == 0 || len(resp.Candidates[0].Content.Parts) == 0 {
  return errors.New("got empty response from model")
}

変更後

Python

from google.genai import types

def get_current_weather(location: str) -> str:
  """Returns the current weather.

  Args:
    location: The city and state, e.g. San Francisco, CA
  """
  return 'sunny'

response = client.models.generate_content(
  model='gemini-2.5-flash',
  contents='What is the weather like in Boston?',
  config=types.GenerateContentConfig(tools=[get_current_weather]),
)

Java

Chat メソッドまたは GenerateContent メソッドを使用して、関数呼び出しを実装します。

Chat の使用

呼び出し可能関数になるメソッドを宣言します。

Method method1 =
    ChatWithFunctionCall.class.getDeclaredMethod("getCurrentWeather", String.class);
Method method2 =
    ChatWithFunctionCall.class.getDeclaredMethod("divideTwoIntegers", int.class, int.class);

コンテンツ構成内のツールに、呼び出し可能な関数として 2 つのメソッドを追加します。

GenerateContentConfig config =
    GenerateContentConfig.builder().tools(Tool.builder().functions(method1, method2)).build();

構成を使用してチャット セッションを作成します。

Chat chatSession = client.chats.create("gemini-2.5-flash", config);

GenerateContentResponse response1 =
    chatSession.sendMessage("what is the weather in San Francisco?");

完全な実装については、ChatWithFunctionCall.java をご覧ください。

GenerateContent の使用

呼び出し可能関数になるメソッドを宣言します。

Method method1 =
  GenerateContentWithFunctionCall.class.getMethod(
    "getCurrentWeather", String.class, String.class);
Method method2 =
  GenerateContentWithFunctionCall.class.getMethod(
    "divideTwoIntegers", Integer.class, Integer.class);

コンテンツ構成内のツールに、呼び出し可能な関数として 2 つのメソッドを追加します。

GenerateContentConfig config =
    GenerateContentConfig.builder().tools(Tool.builder().functions(method1, method2)).build();

構成で generateContent を使用します。

GenerateContentResponse response =
    client.models.generateContent(
        "gemini-2.5-flash",
        "What is the weather in Vancouver? And can you divide 10 by 0?",
        config);

完全な実装については、GenerateContentWithFunctionCall.java をご覧ください。

JavaScript

import {
  FunctionCall,
  FunctionCallingConfigMode,
  FunctionDeclaration,
  GoogleGenAI,
  Type,
} from '@google/genai';

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const controlLightFunctionDeclaration: FunctionDeclaration = {
  name: 'controlLight',
  parameters: {
    type: Type.OBJECT,
    description: 'Set the brightness and color temperature of a room light.',
    properties: {
      brightness: {
        type: Type.NUMBER,
        description:
          'Light level from 0 to 100. Zero is off and 100 is full brightness.',
      },
      colorTemperature: {
        type: Type.STRING,
        description:
          'Color temperature of the light fixture which can be `daylight`, `cool` or `warm`.',
      },
    },
    required: ['brightness', 'colorTemperature'],
  },
};
const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents: 'Dim the lights so the room feels cozy and warm.',
  config: {
    tools: [{functionDeclarations: [controlLightFunctionDeclaration]}],
    toolConfig: {
      functionCallingConfig: {
        mode: FunctionCallingConfigMode.ANY,
        allowedFunctionNames: ['controlLight'],
      },
    },
  },
});

console.debug(response.functionCalls);

Go

package main

import (
  "context"
  "encoding/json"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

var model = flag.String("model", "gemini-2.5-flash", "the model name, e.g. gemini-2.5-flash")

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

  funcName := "getCurrentWeather"
  funcDecl := &genai.FunctionDeclaration{
    Name:        funcName,
    Description: "Get the current weather in a given location",
    Parameters: &genai.Schema{
      Type: genai.TypeObject,
      Properties: map[string]*genai.Schema{
        "location": {
          Type:        genai.TypeString,
          Description: "location",
        },
      },
      Required: []string{"location"},
    },
  }
  // Add the weather function to our model toolbox.
  var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{
    Tools: []*genai.Tool{
      {
        FunctionDeclarations: []*genai.FunctionDeclaration{funcDecl},
      },
    },
  }
  // Call the GenerateContent method.
  result, err := client.Models.GenerateContent(ctx, *model, genai.Text("What's the weather like in Boston?"), config)
  if err != nil {
    log.Fatal(err)
  }
  fmt.Println(result.Candidates[0].Content.Parts[0].FunctionCall.Name)

  // Use synthetic data to simulate a response from the external API.
  // In a real application, this would come from an actual weather API.
  mockAPIResp, err := json.Marshal(map[string]string{
    "location":         "Boston",
    "temperature":      "38",
    "temperature_unit": "F",
    "description":      "Cold and cloudy",
    "humidity":         "65",
    "wind":             `{"speed": "10", "direction": "NW"}`,
  })
  if err != nil {
    log.Fatal(err)
  }

  funcResp := &genai.FunctionResponse{
    Name: funcName,
    Response: map[string]any{
      "content": mockAPIResp,
    },
  }

  // Return the API response to the model allowing it to complete its response.
  mockedFunctionResponse := []*genai.Content{
    &genai.Content{
      Role: "user",
      Parts: []*genai.Part{
        &genai.Part{Text: "What's the weather like in Boston?"},
      },
    },
    result.Candidates[0].Content,
    &genai.Content{
      Role: "tool",
      Parts: []*genai.Part{
        &genai.Part{FunctionResponse: funcResp},
      },
    },
  }
  result, err = client.Models.GenerateContent(ctx, *model, mockedFunctionResponse, config)
  if err != nil {
    log.Fatal(err)
  }
  fmt.Println(result.Text())
}

func main() {
  ctx := context.Background()
  flag.Parse()
  run(ctx)
}

グラウンディング

グラウンディングとは、モデルに外部のドメイン固有の情報を提供して、回答の精度、関連性、一貫性を高めるプロセスです。グラウンディングの実装を Vertex AI SDK から Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

model = generative_models.GenerativeModel(GEMINI_MODEL_NAME)
google_search_retriever_tool = (
  generative_models.Tool.from_google_search_retrieval(
    generative_models.grounding.GoogleSearchRetrieval()
  )
)
response = model.generate_content(
  "Why is sky blue?",
  tools=[google_search_retriever_tool],
  generation_config=generative_models.GenerationConfig(temperature=0),
)

Java

import com.google.cloud.vertexai.api.GroundingMetadata;

Tool googleSearchTool =
  Tool.newBuilder()
    .setGoogleSearch(GoogleSearch.newBuilder())
    .build();

GenerativeModel model =
  new GenerativeModel(modelName, vertexAI)
    .withTools(Collections.singletonList(googleSearchTool));

GenerateContentResponse response = model.generateContent("Why is the sky blue?");

GroundingMetadata groundingMetadata = response.getCandidates(0).getGroundingMetadata();
String answer = ResponseHandler.getText(response);

JavaScript

const {VertexAI} = require('@google-cloud/vertexai');

const vertexAI = new VertexAI({project: projectId, location: location});

const generativeModelPreview = vertexAI.preview.getGenerativeModel({
  model: model,
  generationConfig: {maxOutputTokens: 256},
});

const googleSearchTool = {
  googleSearch: {},
};

const request = {
  contents: [{role: 'user', parts: [{text: 'Why is the sky blue?'}]}],
  tools: [googleSearchTool],
};

const result = await generativeModelPreview.generateContent(request);
const response = await result.response;
const groundingMetadata = response.candidates[0].groundingMetadata;
console.log(
  'Response: ',
  JSON.stringify(response.candidates[0].content.parts[0].text)
);
console.log('GroundingMetadata is: ', JSON.stringify(groundingMetadata));

Go

グラウンディングは Go Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

変更後

Python

from google.genai import types
from google.genai import Client

client = Client(
  vertexai=True,
  project=GOOGLE_CLOUD_PROJECT,
  location=GOOGLE_CLOUD_LOCATION
)

response = client.models.generate_content(
  model='gemini-2.5-flash-exp',
  contents='Why is the sky blue?',
  config=types.GenerateContentConfig(
  tools=[types.Tool(google_search=types.GoogleSearch())]),
)

Java

Tool モジュールをインポートします。

import com.google.genai.types.Tool;

構成で Google 検索ツールを設定します。

Tool googleSearchTool = Tool.builder().googleSearch(GoogleSearch.builder()).build();

コンテンツ構成にツールを追加します。

GenerateContentConfig config =
    GenerateContentConfig.builder()
        ...
        .tools(googleSearchTool)
        .build();

完全な実装については、GenerateContentWithConfigs.java をご覧ください。

JavaScript

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

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});
const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents:
    'What is the sum of the first 50 prime numbers? Generate and run code for the calculation, and make sure you get all 50.',
  config: {
    tools: [{googleSearch: {}}],
  },
});
console.debug(JSON.stringify(response?.candidates?.[0]?.groundingMetadata));

Go

package main

import (
  "context"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

var model = flag.String("model", "gemini-2.5-flash", "the model name, e.g. gemini-2.5-flash")

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

  // Add the Google Search grounding tool to the GenerateContentConfig.
  var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{
    Tools: []*genai.Tool{
      {
        GoogleSearch: &genai.GoogleSearch{},
      },
    },
  }
  // Call the GenerateContent method.
  result, err := client.Models.GenerateContent(ctx, *model, genai.Text("Why is the sky blue?"), config)
  if err != nil {
    log.Fatal(err)
  }
  fmt.Println(result.Text())
}

func main() {
  ctx := context.Background()
  flag.Parse()
  run(ctx)
}

安全性設定

安全性設定は、ユーザーがモデルのレスポンスを管理できるようにする構成可能なパラメータです。ヘイトスピーチ、性的コンテンツ、暴力など、特定の有害なカテゴリに関連するコンテンツをフィルタリングまたはブロックできます。安全性設定の実装を、Google Gen AI SDK を使用する次のコードを含む Vertex AI SDK に置き換えます。

変更前

Python

model = generative_models.GenerativeModel(
  GEMINI_MODEL_NAME,
  system_instruction=[
    "Talk like a pirate.",
    "Don't use rude words.",
  ],
)
response = model.generate_content(
  contents="Why is sky blue?",
  generation_config=generative_models.GenerationConfig(
    temperature=0,
    top_p=0.95,
    top_k=20,
    candidate_count=1,
    max_output_tokens=100,
    stop_sequences=["STOP!"],
    response_logprobs=True,
    logprobs=3,
  ),
  safety_settings={
    generative_models.HarmCategory.HARM_CATEGORY_HATE_SPEECH: generative_models.HarmBlockThreshold.BLOCK_MEDIUM_AND_ABOVE,
    generative_models.HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT: generative_models.HarmBlockThreshold.BLOCK_ONLY_HIGH,
    generative_models.HarmCategory.HARM_CATEGORY_HARASSMENT: generative_models.HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    generative_models.HarmCategory.HARM_CATEGORY_SEXUALLY_EXPLICIT: generative_models.HarmBlockThreshold.BLOCK_NONE,
  },
)

Java

import com.google.cloud.vertexai.api.SafetySetting;
import com.google.cloud.vertexai.api.SafetySetting.HarmBlockThreshold;

SafetySetting safetySetting =
  SafetySetting.newBuilder()
    .setCategory(HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT)
    .setThreshold(HarmBlockThreshold.BLOCK_LOW_AND_ABOVE)
    .build();

GenerateContentResponse response =
  model
    .withSafetySetting(Arrays.asList(SafetySetting))
    .generateContent("Please explain LLM?");

JavaScript

const {
  VertexAI,
  HarmCategory,
  HarmBlockThreshold,
} = require('@google-cloud/vertexai');

// Initialize Vertex with your Cloud project and location
const vertexAI = new VertexAI({project: PROJECT_ID, location: LOCATION});

// Instantiate the model
const generativeModel = vertexAI.getGenerativeModel({
  model: MODEL,
  safetySettings: [
    {
      category: HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT,
      threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    },
    {
      category: HarmCategory.HARM_CATEGORY_HARASSMENT,
      threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    },
  ],
});

const request = {
  contents: [{role: 'user', parts: [{text: 'Tell me something dangerous.'}]}],
};

console.log('Prompt:');
console.log(request.contents[0].parts[0].text);
console.log('Streaming Response Text:');

// Create the response stream
const responseStream = await generativeModel.generateContentStream(request);

// Log the text response as it streams
for await (const item of responseStream.stream) {
  if (item.candidates[0].finishReason === 'SAFETY') {
    console.log('This response stream terminated due to safety concerns.');
    break;
  } else {
    process.stdout.write(item.candidates[0].content.parts[0].text);
  }
}
console.log('This response stream terminated due to safety concerns.');

Go

package safetysettings

import (
  "context"
  "fmt"
  "io"

  "cloud.google.com/go/vertexai/genai"
)

// generateContent generates text from prompt and configurations provided.
func generateContent(w io.Writer, projectID, location, modelName string) error {
  // location := "us-central1"
  // model := "gemini-2.5-flash"
  ctx := context.Background()

  client, err := genai.NewClient(ctx, projectID, location)
  if err != nil {
    return err
  }
  defer client.Close()

  model := client.GenerativeModel(modelName)
  model.SetTemperature(0.8)

  // configure the safety settings thresholds
  model.SafetySettings = []*genai.SafetySetting{
    {
      Category:  genai.HarmCategoryHarassment,
      Threshold: genai.HarmBlockLowAndAbove,
    },
    {
      Category:  genai.HarmCategoryDangerousContent,
      Threshold: genai.HarmBlockLowAndAbove,
    },
  }

  res, err := model.GenerateContent(ctx, genai.Text("Hello, say something mean to me."))
  if err != nil {
    return fmt.Errorf("unable to generate content: %v", err)
  }
  fmt.Fprintf(w, "generate-content response: %v\n", res.Candidates[0].Content.Parts[0])

  fmt.Fprintf(w, "safety ratings:\n")
  for _, r := range res.Candidates[0].SafetyRatings {
    fmt.Fprintf(w, "\t%+v\n", r)
  }

  return nil
}

変更後

Python

from google.genai import types

response = client.models.generate_content(
  model='gemini-2.5-flash',
  contents='Say something bad.',
  config=types.GenerateContentConfig(
    safety_settings=[
      types.SafetySetting(
        category='HARM_CATEGORY_HATE_SPEECH',
        threshold='BLOCK_ONLY_HIGH',
      )
    ]
  ),
)

Java

HarmBlockThreshold、HarmCategory、SafetySetting の各モジュールをインポートします。

import com.google.genai.types.HarmBlockThreshold;
import com.google.genai.types.HarmCategory;
import com.google.genai.types.SafetySetting;

構成で安全性設定を設定します。

ImmutableList<SafetySetting> safetySettings =
  ImmutableList.of(
    SafetySetting.builder()
      .category(HarmCategory.Known.HARM_CATEGORY_HATE_SPEECH)
      .threshold(HarmBlockThreshold.Known.BLOCK_ONLY_HIGH)
      .build(),
    SafetySetting.builder()
      .category(HarmCategory.Known.HARM_CATEGORY_DANGEROUS_CONTENT)
      .threshold(HarmBlockThreshold.Known.BLOCK_LOW_AND_ABOVE)
      .build());

コンテンツ構成に安全性設定を追加します。

GenerateContentConfig config =
GenerateContentConfig.builder()
    ...
    .safetySettings(safetySettings)
    .build();

完全な実装については、GenerateContentWithConfigs.java をご覧ください。

JavaScript

import {
  GoogleGenAI,
  HarmBlockMethod,
  HarmBlockThreshold,
  HarmCategory,
} from '@google/genai';

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents: 'say something bad',
  config: {
    safetySettings: [
      {
        method: HarmBlockMethod.SEVERITY,
        category: HarmCategory.HARM_CATEGORY_HATE_SPEECH,
        threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
      },
      {
        method: HarmBlockMethod.SEVERITY,
        category: HarmCategory.HARM_CATEGORY_HARASSMENT,
        threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
      },
    ],
  },
});

console.debug(JSON.stringify(response?.candidates?.[0]?.safetyRatings));

Go

package main

import (
  "context"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

var model = flag.String("model", "gemini-2.5-flash", "the model name, e.g. gemini-2.5-flash")

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

  var safetySettings []*genai.SafetySetting = []*genai.SafetySetting{
    {
      Category:  genai.HarmCategoryHarassment,
      Threshold: genai.HarmBlockThresholdBlockMediumAndAbove,
    },
    {
      Category:  genai.HarmCategoryDangerousContent,
      Threshold: genai.HarmBlockThresholdBlockMediumAndAbove,
    },
  }
  var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{
    SafetySettings: safetySettings,
  }
  // Call the GenerateContent method.
  result, err := client.Models.GenerateContent(ctx, *model, genai.Text("What is your name?"), config)
  if err != nil {
    log.Fatal(err)
  }
  fmt.Println(result.Text())
}

func main() {
  ctx := context.Background()
  flag.Parse()
  run(ctx)
}

チャット セッション

チャット セッションは、会話型のインタラクションです。モデルは、以前のメッセージを呼び出して現在のレスポンスの情報として使用することで、複数のターンにわたってコンテキストを維持します。Vertex AI SDK の実装を、Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

model = GenerativeModel(
  "gemini-2.5-flash",
  # You can specify tools when creating a model to avoid having to send them with every request.
  tools=[weather_tool],
  tool_config=tool_config,
)
chat = model.start_chat()
print(chat.send_message("What is the weather like in Boston?"))
print(chat.send_message(
  Part.from_function_response(
    name="get_current_weather",
    response={
      "content": {"weather_there": "super nice"},
      }
  ),
))

Java

import com.google.cloud.vertexai.generativeai.ChatSession;

GenerativeModel model = new GenerativeModel("gemini-2.5-flash", vertexAi);
ChatSession chat = model.startChat();

ResponseStream<GenerateContentResponse> response = chat
  .sendMessageStream("Can you tell me a story about cheese in 100 words?");
ResponseStream<GenerateContentResponse> anotherResponse = chat
  .sendMessageStream("Can you modify the story to be written for a 5 year old?");

JavaScript

const {VertexAI} = require('@google-cloud/vertexai');

const chat = generativeModel.startChat({});

const result1 = await chat.sendMessage('Hello');
const response1 = await result1.response;
console.log('Chat response 1: ', JSON.stringify(response1));

const result2 = await chat.sendMessage(
  'Can you tell me a scientific fun fact?'
);
const response2 = await result2.response;
console.log('Chat response 2: ', JSON.stringify(response2));

Go

import (
  "context"
  "errors"
  "fmt"

  "cloud.google.com/go/vertexai/genai"
)

prompt := "Do you have the Pixel 8 Pro in stock?"
fmt.Fprintf(w, "Question: %s\n", prompt)
resp, err := chat.SendMessage(ctx, genai.Text(prompt))

変更後

Python

同期

chat = client.chats.create(model='gemini-2.5-flash')
response = chat.send_message('tell me a story')
print(response.text)
response = chat.send_message('summarize the story you told me in 1 sentence')
print(response.text)

非同期

chat = client.aio.chats.create(model='gemini-2.5-flash')
response = await chat.send_message('tell me a story')
print(response.text)

同期ストリーミング

chat = client.chats.create(model='gemini-2.5-flash')
for chunk in chat.send_message_stream('tell me a story'):
    print(chunk.text, end='')

非同期ストリーミング

chat = client.aio.chats.create(model='gemini-2.5-flash')
async for chunk in await chat.send_message_stream('tell me a story'):
    print(chunk.text, end='') # end='' is optional, for demo purposes.

Java

Chat モジュールと GenerateContentResponse モジュールをインポートします。

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

チャット セッションを作成します。

Chat chatSession = client.chats.create("gemini-2.5-flash");

GenerateContentResponse を使用してプロンプトを指定します。

GenerateContentResponse response =
    chatSession
      .sendMessage("Can you tell me a story about cheese in 100 words?");
// Gets the text string from the response by the quick accessor method `text()`.
System.out.println("Unary response: " + response.text());

GenerateContentResponse response2 =
    chatSession
      .sendMessage("Can you modify the story to be written for a 5 year old?");
// Gets the text string from the second response.
System.out.println("Unary response: " + response2.text());

完全な実装については、ChatWithHistory.java をご覧ください。

JavaScript

import {GoogleGenAI} from '@google/genai';
const chat = ai.chats.create({model: 'gemini-2.5-flash'});

const response = await chat.sendMessage({message: 'Why is the sky blue?'});
console.debug('chat response 1: ', response.text);
const response2 = await chat.sendMessage({message: 'Why is the sunset red?'});
console.debug('chat response 2: ', response2.text);

const history = chat.getHistory();
for (const content of history) {
  console.debug('chat history: ', JSON.stringify(content, null, 2));
}

Go

package main

import (
  "context"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

var model = flag.String("model", "gemini-2.5-flash", "the model name, e.g. gemini-2.5-flash")

var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{Temperature: genai.Ptr[float32](0.5)}

// Create a new Chat.
chat, err := client.Chats.Create(ctx, *model, config, nil)

// Send first chat message.
result, err := chat.SendMessage(ctx, genai.Part{Text: "What's the weather in San Francisco?"})
if err != nil {
  log.Fatal(err)
}
fmt.Println(result.Text())

// Send second chat message.
result, err = chat.SendMessage(ctx, genai.Part{Text: "How about New York?"})
if err != nil {
  log.Fatal(err)
}
fmt.Println(result.Text())

マルチモーダル入力

マルチモーダル入力とは、モデルがテキスト以外のデータ型（画像、音声、動画など）の情報を処理して理解する機能のことです。実装を Vertex AI SDK から Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

from vertexai.generative_models import GenerativeModel, Image
vision_model = GenerativeModel("gemini-2.5-flash-vision")

# Local image
image = Image.load_from_file("image.jpg")
print(vision_model.generate_content(["What is shown in this image?", image]))

# Image from Cloud Storage
image_part = generative_models.Part.from_uri("gs://download.tensorflow.org/example_images/320px-Felis_catus-cat_on_snow.jpg", mime_type="image/jpeg")
print(vision_model.generate_content([image_part, "Describe this image?"]))

# Text and video
video_part = Part.from_uri("gs://cloud-samples-data/video/animals.mp4", mime_type="video/mp4")
print(vision_model.generate_content(["What is in the video? ", video_part]))

Java

import com.google.cloud.vertexai.generativeai.ContentMaker;

GenerativeModel model = new GenerativeModel("gemini-2.5-flash-vision", vertexAi);

ResponseStream<GenerateContentResponse> stream =
  model.generateContentStream(ContentMaker.fromMultiModalData(
    "Please describe this image",
    PartMaker.fromMimeTypeAndData("image/jpeg", IMAGE_URI)
  ));

JavaScript

const {VertexAI, HarmBlockThreshold, HarmCategory} = require('@google-cloud/vertexai');

// Initialize Vertex with your Cloud project and location
const vertex_ai = new VertexAI({project: project, location: location});

// Instantiate the model
const generativeVisionModel = vertex_ai.getGenerativeModel({
    model: 'gemini-ultra-vision',
});

async function multiPartContent() {
    const filePart = {file_data: {file_uri: "gs://sararob_imagegeneration_test/kitten.jpeg", mime_type: "image/jpeg"}};
    const textPart = {text: 'What is this picture about?'};

    const request = {
        contents: [{role: 'user', parts: [textPart, filePart]}],
      };

    const resp = await generativeVisionModel.generateContentStream(request);
    const contentResponse = await resp.response;
    console.log(JSON.stringify(contentResponse));
}

multiPartContent();

Go

画像

import (
  "context"
  "encoding/json"
  "fmt"
  "io"

  "cloud.google.com/go/vertexai/genai"
)

img := genai.FileData{
  MIMEType: "image/jpeg",
  FileURI:  "gs://generativeai-downloads/images/scones.jpg",
}
prompt := genai.Text("What is in this image?")

resp, err := gemini.GenerateContent(ctx, img, prompt)
if err != nil {
  return fmt.Errorf("error generating content: %w", err)
}

動画

package multimodalvideoaudio

import (
  "context"
  "errors"
  "fmt"
  "io"
  "mime"
  "path/filepath"

  "cloud.google.com/go/vertexai/genai"
)

part := genai.FileData{
  MIMEType: mime.TypeByExtension(filepath.Ext("pixel8.mp4")),
  FileURI:  "gs://cloud-samples-data/generative-ai/video/pixel8.mp4",
}

res, err := model.GenerateContent(ctx, part, genai.Text(`
    Provide a description of the video.
    The description should also contain anything important which people say in the video.
`))

変更後

Python

from google import genai
from google.genai.types import HttpOptions, Part

client = genai.Client(http_options=HttpOptions(api_version="v1"))
response = client.models.generate_content(
    model="gemini-2.5-flash",
    contents=[
        Part.from_uri(
            file_uri="gs://cloud-samples-data/generative-ai/video/ad_copy_from_video.mp4",
            mime_type="video/mp4",
        ),
        "What is in the video?",
    ],
)
print(response.text)

Java

GenerateContentResponse モジュールをインポートします。

import com.google.genai.types.GenerateContentResponse;

マルチモーダル プロンプトでテキスト、画像、動画を組み合わせて指定します。

Content content =
  Content.fromParts(
    Part.fromText("describe the image"),
    Part.fromUri("gs://cloud-samples-data/generative-ai/image/scones.jpg", "image/jpeg"));

結合したプロンプトをモデルに提供します。

GenerateContentResponse response =
  client.models.generateContent("gemini-2.5-flash", content, null);

完全な実装については、GenerateContentWithImageInput.java をご覧ください。

JavaScript

const filePart = {file_data: {file_uri: "gs://sararob_imagegeneration_test/kitten.jpeg", mime_type: "image/jpeg"}};
const textPart = {text: 'What is this picture about?'};
const contents = [{role: 'user', parts: [textPart, filePart]}];
const response = await ai.models.generateContentStream({
  model: 'gemini-2.5-flash-exp',
  contents: contents,
});
let i = 0;
for await (const chunk of response) {
  const text = chunk.text;
  if (text) {
    console.debug(text);
  }
}

Go

画像

package main

import (
  "context"
  "encoding/json"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

config := &genai.GenerateContentConfig{}
config.ResponseModalities = []string{"IMAGE", "TEXT"}
// Call the GenerateContent method.
result, err := client.Models.GenerateContent(ctx, *model, genai.Text("Generate a story about a cute baby turtle in a 3d digital art style. For each scene, generate an image."), config)
if err != nil {
  log.Fatal(err)
}

映像と音声

package multimodalvideoaudio

import (
  "context"
  "errors"
  "fmt"
  "io"
  "mime"
  "path/filepath"

  "cloud.google.com/go/vertexai/genai"
)

part := genai.FileData{
  MIMEType: mime.TypeByExtension(filepath.Ext("pixel8.mp4")),
  FileURI:  "gs://cloud-samples-data/generative-ai/video/pixel8.mp4",
}

res, err := model.GenerateContent(ctx, part, genai.Text(`
    Provide a description of the video.
    The description should also contain anything important which people say in the video.
`))

テキスト生成

テキスト生成は、モデルが指定されたプロンプトに基づいて人間が作成したかのようなテキスト コンテンツを生成するプロセスです。実装を Vertex AI SDK に置き換えます。次のコードは Google Gen AI SDK を使用します。

同期生成

変更前

Python

response = model.generate_content(
  "Why is sky blue?",
  generation_config=generative_models.GenerationConfig(temperature=0),
)
assert response.text

Java

import com.google.cloud.vertexai.api.GenerateContentResponse;
GenerativeModel model = new GenerativeModel("gemini-2.5-flash", vertexAi);
GenerateContentResponse response = model.generateContent("How are you?");

JavaScript

Vertex AI SDK と Google Gen AI SDK の両方で、JavaScript の非同期テキスト生成のみがサポートされています。

Go

gemini := client.GenerativeModel(modelName)
prompt := genai.Text(
  "What's a good name for a flower shop that specializes in selling bouquets of dried flowers?")

resp, err := gemini.GenerateContent(ctx, prompt)

変更後

Python

response = client.models.generate_content(
  model='gemini-2.5-flash', contents='Why is the sky blue?'
)
print(response.text)

Java

GenerateContentResponse モジュールをインポートします。

import com.google.genai.types.GenerateContentResponse;

generateContent を使用してテキストを生成します。

GenerateContentResponse response =
  client.models.generateContent("gemini-2.5-flash", "What is your name?", null);

完全な実装については、GenerateContent.java をご覧ください。

JavaScript

Vertex AI SDK と Google Gen AI SDK の両方で、JavaScript の非同期テキスト生成のみがサポートされています。

Go

var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{Temperature: genai.Ptr[float32](0)}
// Call the GenerateContent method.
result, err := client.Models.GenerateContent(ctx, *model, genai.Text("What is your name?"), config)

非同期生成

変更前

Python

response = await model.generate_content_async(
  "Why is sky blue?",
  generation_config=generative_models.GenerationConfig(temperature=0),
)

Java

import com.google.cloud.vertexai.api.GenerateContentResponse;

GenerativeModel model = new GenerativeModel("gemini-2.5-flash", vertexAi);
ApiFuture<GenerateContentResponse> future = model.generateContentAsync("How are you?");
GenerateContentResponse response = future.get();

JavaScript

const {VertexAI} = require('@google-cloud/vertexai');

// Initialize Vertex with your Cloud project and location
const vertexAI = new VertexAI({project: projectId, location: location});

// Instantiate the model
const generativeModel = vertexAI.getGenerativeModel({
  model: model,
});

const request = {
  contents: [
    {
      role: 'user',
      parts: [
        {
          text: 'Write a story about a magic backpack.',
        },
      ],
    },
  ],
};

console.log(JSON.stringify(request));
const result = await generativeModel.generateContent(request);
console.log(result.response.text);

Go

該当なし: Go は非同期オペレーションなしで同時実行タスクを管理します。

変更後

Python

response = await client.aio.models.generate_content(
  model='gemini-2.5-flash', contents='Tell me a story in 300 words.'
)

print(response.text)

Java

GenerateContentResponse モジュールをインポートします。

import com.google.genai.types.GenerateContentResponse;

非同期でテキストを生成します。

CompletableFuture<GenerateContentResponse> responseFuture =
  client.async.models.generateContent(
    "gemini-2.5-flash", "Introduce Google AI Studio.", null);

responseFuture
  .thenAccept(
    response -> {
      System.out.println("Async response: " + response.text());
    })
  .join();

完全な実装については、GenerateContentAsync.java をご覧ください。

JavaScript

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents: 'why is the sky blue?',
});

console.debug(response.text);

Go

該当なし: Go は非同期オペレーションなしで同時実行タスクを管理します。

ストリーミング

変更前

Python

同期ストリーミング

stream = model.generate_content(
  "Why is sky blue?",
  stream=True,
  generation_config=generative_models.GenerationConfig(temperature=0),
)
for chunk in stream:
  assert (
    chunk.text
    or chunk.candidates[0].finish_reason
    is generative_models.FinishReason.STOP
  )

非同期ストリーミング

async_stream = await model.generate_content_async(
  "Why is sky blue?",
  stream=True,
  generation_config=generative_models.GenerationConfig(temperature=0),
)
async for chunk in async_stream:
  assert (
    chunk.text
    or chunk.candidates[0].finish_reason
    is generative_models.FinishReason.STOP
  )

Java

import com.google.cloud.vertexai.generativeai.ResponseStream;
import com.google.cloud.vertexai.api.GenerateContentResponse;

GenerativeModel model = new GenerativeModel("gemini-2.5-flash", vertexAi);
ResponseStream<GenerateContentResponse> responseStream = model.generateContentStream("How are you?");

JavaScript

// Initialize Vertex with your Cloud project and location
const vertexAI = new VertexAI({project: projectId, location: location});

// Instantiate the model
const generativeModel = vertexAI.getGenerativeModel({
  model: model,
});

const request = {
  contents: [{role: 'user', parts: [{text: 'What is Node.js?'}]}],
};

console.log('Prompt:');
console.log(request.contents[0].parts[0].text);
console.log('Streaming Response Text:');

// Create the response stream
const responseStream = await generativeModel.generateContentStream(request);

// Log the text response as it streams
for await (const item of responseStream.stream) {
  process.stdout.write(item.candidates[0].content.parts[0].text);
}

Go

package streamtextbasic

import (
  "context"
  "errors"
  "fmt"
  "io"

  "cloud.google.com/go/vertexai/genai"
  "google.golang.org/api/iterator"
)

model := client.GenerativeModel(modelName)

iter := model.GenerateContentStream(
  ctx,
  genai.Text("Write a story about a magic backpack."),
)
for {
  resp, err := iter.Next()
  fmt.Fprint(w, "generated response: ")
  for _, c := range resp.Candidates {
    for _, p := range c.Content.Parts {
      fmt.Fprintf(w, "%s ", p)
    }
  }
}

変更後

Python

同期ストリーミング

for chunk in client.models.generate_content_stream(
  model='gemini-2.5-flash', contents='Tell me a story in 300 words.'
):
  print(chunk.text, end='')

非同期ストリーミング

async for chunk in await client.aio.models.generate_content_stream(
  model='gemini-2.5-flash', contents='Tell me a story in 300 words.'
):
  print(chunk.text, end='')

Java

ResponseStream モジュールと GenerateContentResponse モジュールをインポートします。

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

モデルにプロンプトを指定して結果をストリーミングします。

ResponseStream<GenerateContentResponse> responseStream =
  client.models.generateContentStream(
    "gemini-2.5-flash", "Tell me a story in 300 words.", null);

System.out.println("Streaming response: ");
for (GenerateContentResponse res : responseStream) {
  System.out.print(res.text());
}

完全な実装については、GenerateContentAsync.java をご覧ください。

JavaScript

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const response = await ai.models.generateContentStream({
  model: 'gemini-2.5-flash-exp',
  contents:
    'Generate a story about a cute baby turtle in a 3d digital art style. For each scene, generate an image.',
  config: {
    responseModalities: [Modality.IMAGE, Modality.TEXT],
  },
});

let i = 0;
for await (const chunk of response) {
  const text = chunk.text;
  const data = chunk.data;
  if (text) {
    console.debug(text);
  } else if (data) {
    const fileName = `generate_content_streaming_image_${i++}.png`;
    console.debug(`Writing response image to file: ${fileName}.`);
    fs.writeFileSync(fileName, data);
  }
}

Go

client, err := genai.NewClient(ctx, nil)
var config *genai.GenerateContentConfig = &genai.GenerateContentConfig{SystemInstruction: &genai.Content{Parts: []*genai.Part{&genai.Part{Text: "You are a story writer."}}}}
// Call the GenerateContent method.
for result, err := range client.Models.GenerateContentStream(ctx, *model, genai.Text("Tell me a story in 300 words."), config) {
  if err != nil {
    log.Fatal(err)
  }
  fmt.Print(result.Text())
}

画像生成

画像生成とは、モデルがテキストによる説明やその他の入力モードから画像を作成するプロセスです。実装を Vertex AI SDK に置き換えます。次のコードは Google Gen AI SDK を使用します。

変更前

Python

model = ImageGenerationModel.from_pretrained("imagegeneration@002")
response = model.generate_images(
    prompt="Astronaut riding a horse",
    # Optional:
    number_of_images=1,
    seed=0,
)
response[0].show()
response[0].save("image1.png")

Java

画像生成は Java Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

JavaScript

画像生成は JavaScript Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

Go

画像生成は Go Vertex AI SDK ではサポートされていませんが、Google Gen AI SDK ではサポートされています。

変更後

Python

from google.genai import types

# Generate Image
response1 = client.models.generate_images(
    model='imagen-3.0-generate-002',
    prompt='An umbrella in the foreground, and a rainy night sky in the background',
    config=types.GenerateImagesConfig(
        number_of_images=1,
        include_rai_reason=True,
        output_mime_type='image/jpeg',
    ),
)
response1.generated_images[0].image.show()

Java

import com.google.genai.types.GenerateImagesConfig;
import com.google.genai.types.GenerateImagesResponse;
import com.google.genai.types.Image;

GenerateImagesConfig generateImagesConfig =
    GenerateImagesConfig.builder()
        .numberOfImages(1)
        .outputMimeType("image/jpeg")
        .includeSafetyAttributes(true)
        .build();

GenerateImagesResponse generatedImagesResponse =
    client.models.generateImages(
        "imagen-3.0-generate-002", "Robot holding a red skateboard", generateImagesConfig);

Image generatedImage = generatedImagesResponse.generatedImages().get().get(0).image().get();

JavaScript

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});
const response = await ai.models.generateImages({
  model: 'imagen-3.0-generate-002',
  prompt: 'Robot holding a red skateboard',
  config: {
    numberOfImages: 1,
    includeRaiReason: true,
  },
});

console.debug(response?.generatedImages?.[0]?.image?.imageBytes);

Go

import (
  "encoding/json"
  "google.golang.org/genai"
)

fmt.Println("Generate image example.")
response1, err := client.Models.GenerateImages(
  ctx, "imagen-3.0-generate-002",
  /*prompt=*/ "An umbrella in the foreground, and a rainy night sky in the background",
  &genai.GenerateImagesConfig{
    IncludeRAIReason:        true,
    IncludeSafetyAttributes: true,
    OutputMIMEType:          "image/jpeg",
  },
)

生成制御機能

生成制御とは、自由形式のテキストを生成するのではなく、特定の制約、形式、スタイル、属性に準拠するようにモデルの出力をガイドするプロセスを指します。実装を Vertex AI SDK から Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

_RESPONSE_SCHEMA_STRUCT = {
    "type": "object",
    "properties": {
        "location": {
            "type": "string",
        },
    },
    "required": ["location"],
}

response = model.generate_content(
    contents="Why is sky blue? Respond in JSON Format.",
    generation_config=generative_models.GenerationConfig(
        ...
        response_schema=_RESPONSE_SCHEMA_STRUCT,
    ),
)

Java

import com.google.cloud.vertexai.api.Schema;
import com.google.cloud.vertexai.api.Type;
import com.google.cloud.vertexai.generativeai.ContentMaker;
import com.google.cloud.vertexai.generativeai.PartMaker;

GenerationConfig generationConfig = GenerationConfig.newBuilder()
  .setResponseMimeType("application/json")
  .setResponseSchema(Schema.newBuilder()
    .setType(Type.ARRAY)
    .setItems(Schema.newBuilder()
      .setType(Type.OBJECT)
      .putProperties("object", Schema.newBuilder().setType(Type.STRING).build())
      .build())
    .build())
  .build();

GenerativeModel model = new GenerativeModel(modelName, vertexAI)
  .withGenerationConfig(generationConfig);

GenerateContentResponse response = model.generateContent(
  ContentMaker.fromMultiModalData(
    PartMaker.fromMimeTypeAndData("image/jpeg",
      "gs://cloud-samples-data/generative-ai/image/office-desk.jpeg"),
    PartMaker.fromMimeTypeAndData("image/jpeg",
      "gs://cloud-samples-data/generative-ai/image/gardening-tools.jpeg"),
    "Generate a list of objects in the images."
  )
);

JavaScript

// Initialize Vertex with your Cloud project and location
const vertex_ai = new VertexAI({project: project, location: location});

// Instantiate the model
const responseSchema = {
  type: 'ARRAY',
  items: {
    type: 'OBJECT',
    properties: {
      'recipeName': {
        type: 'STRING',
        description: 'Name of the recipe',
        nullable: false,
      },
    },
    required: ['recipeName'],
  },
};

const generativeModel = vertex_ai.getGenerativeModel({
    model: 'gemini-2.5-flash',
    generationConfig: {
      responseSchema: responseSchema,
      responseMimeType: 'application/json',
    }
  });

async function generateContentControlledOutput() {

  const req = {
    contents: [{role: 'user', parts: [{text: 'list 3 popular cookie recipe'}]}],
  };

  const resp = await generativeModel.generateContent(req);

  console.log('aggregated response: ', JSON.stringify(resp.response));
};

generateContentControlledOutput();

Go

import (
  "context"
  "cloud.google.com/go/vertexai/genai"
)

model.GenerationConfig.ResponseMIMEType = "application/json"

// Build an OpenAPI schema, in memory
model.GenerationConfig.ResponseSchema = &genai.Schema{
  Type: genai.TypeArray,
  Items: &genai.Schema{
    Type: genai.TypeArray,
    Items: &genai.Schema{
      Type: genai.TypeObject,
      Properties: map[string]*genai.Schema{
        "object": {
          Type: genai.TypeString,
        },
      },
    },
  },
}

img1 := genai.FileData{
  MIMEType: "image/jpeg",
  FileURI:  "gs://cloud-samples-data/generative-ai/image/office-desk.jpeg",
}

img2 := genai.FileData{
  MIMEType: "image/jpeg",
  FileURI:  "gs://cloud-samples-data/generative-ai/image/gardening-tools.jpeg",
}

prompt := "Generate a list of objects in the images."

res, err := model.GenerateContent(ctx, img1, img2, genai.Text(prompt))

変更後

Python

response_schema = {
  "type": "ARRAY",
  "items": {
    "type": "OBJECT",
    "properties": {
      "recipe_name": {"type": "STRING"},
      "ingredients": {"type": "ARRAY", "items": {"type": "STRING"}},
    },
    "required": ["recipe_name", "ingredients"],
  },
}

prompt = """
  List a few popular cookie recipes.
"""

response = client.models.generate_content(
  model="gemini-2.5-flash",
  contents=prompt,
  config={
    "response_mime_type": "application/json",
    "response_schema": response_schema,
  },
)

Java

Schema モジュールと Type モジュールをインポートします。

import com.google.genai.types.Schema;
import com.google.genai.types.Type;

レスポンス スキーマを作成します。

Schema schema =
  Schema.builder()
    .type(Type.Known.ARRAY)
    .items(
      Schema.builder()
        .type(Type.Known.OBJECT)
        .properties(
          ImmutableMap.of(
            "recipe_name",
            Schema.builder().type(Type.Known.STRING).build(),
            "ingredients",
            Schema.builder()
              .type(Type.Known.ARRAY)
              .items(Schema.builder().type(Type.Known.STRING))
              .build()))
        .required("recipe_name", "ingredients"))
    .build();

コンテンツ構成にスキーマを追加します。

GenerateContentConfig config =
  GenerateContentConfig.builder()
    .responseMimeType("application/json")
    .candidateCount(1)
    .responseSchema(schema)
    .build();

構成を使用してレスポンスを生成します。

GenerateContentResponse response =
client.models.generateContent(
    "gemini-2.5-flash", "List a few popular cookie recipes.", config);

完全な実装については、GenerateContentWithResponseSchema.java をご覧ください。

JavaScript

const ai = new GoogleGenAI({
  vertexai: true,
  project: GOOGLE_CLOUD_PROJECT,
  location: GOOGLE_CLOUD_LOCATION,
});

const response = await ai.models.generateContent({
  model: 'gemini-2.5-flash',
  contents: 'List 3 popular cookie recipes.',
  config: {
    responseMimeType: 'application/json',
    responseSchema: {
      type: Type.ARRAY,
      items: {
        type: Type.OBJECT,
        properties: {
          'recipeName': {
            type: Type.STRING,
            description: 'Name of the recipe',
            nullable: false,
          },
        },
        required: ['recipeName'],
      },
    },
  },
});

console.debug(response.text);

Go

import (
  "context"
  "encoding/json"

  genai "google.golang.org/genai"
)

cacheContents := []*genai.Content{
  {
    Parts: []*genai.Part{
      {FileData: &genai.FileData{
        FileURI:  "gs://cloud-samples-data/generative-ai/pdf/2312.11805v3.pdf",
        MIMEType: "application/pdf",
      }},
      {FileData: &genai.FileData{
        FileURI:  "gs://cloud-samples-data/generative-ai/pdf/2403.05530.pdf",
        MIMEType: "application/pdf",
      }},
    },
    Role: "user",
  },
}

config := &genai.CreateCachedContentConfig{
  Contents: cacheContents,
  SystemInstruction: &genai.Content{
    Parts: []*genai.Part{
      {Text: systemInstruction},
    },
  },
  DisplayName: "example-cache",
  TTL:         "86400s",
}

res, err := client.Caches.Create(ctx, modelName, config)
if err != nil {
  return "", fmt.Errorf("failed to create content cache: %w", err)
}

cachedContent, err := json.MarshalIndent(res, "", "  ")
if err != nil {
  return "", fmt.Errorf("failed to marshal cache info: %w", err)
}

トークンのカウント

トークンは、モデルが処理、分析、生成するテキストの基本単位（文字、単語、フレーズ）です。レスポンス内のトークンをカウントまたは計算するには、実装を Vertex AI SDK から Google Gen AI SDK を使用する次のコードに置き換えます。

変更前

Python

content = ["Why is sky blue?", "Explain it like I'm 5."]

response = model.count_tokens(content)

Java

import com.google.cloud.vertexai.api.CountTokensResponse;

CountTokensResponse response = model.countTokens(textPrompt);

int promptTokenCount = response.getTotalTokens();
int promptCharCount = response.getTotalBillableCharacters();

GenerateContentResponse contentResponse = model.generateContent(textPrompt);

int tokenCount = contentResponse.getUsageMetadata().getPromptTokenCount();
int candidateTokenCount = contentResponse.getUsageMetadata().getCandidatesTokenCount();
int totalTokenCount = contentResponse.getUsageMetadata().getTotalTokenCount();

JavaScript

const request = {
    contents: [{role: 'user', parts: [{text: 'How are you doing today?'}]}],
  };
const response = await generativeModel.countTokens(request);
console.log('count tokens response: ', JSON.stringify(response));

Go

package tokencount

import (
  "context"
  "fmt"
  "cloud.google.com/go/vertexai/genai"
)

resp, err := model.CountTokens(ctx, prompt)

fmt.Fprintf(w, "Number of tokens for the prompt: %d\n", resp.TotalTokens)

resp2, err := model.GenerateContent(ctx, prompt)

fmt.Fprintf(w, "Number of tokens for the prompt: %d\n", resp2.UsageMetadata.PromptTokenCount)
fmt.Fprintf(w, "Number of tokens for the candidates: %d\n", resp2.UsageMetadata.CandidatesTokenCount)
fmt.Fprintf(w, "Total number of tokens: %d\n", resp2.UsageMetadata.TotalTokenCount)

変更後

Python

トークン数をカウントする

response = client.models.count_tokens(
    model='gemini-2.5-flash',
    contents='why is the sky blue?',
)
print(response)

コンピューティング トークン

response = client.models.compute_tokens(
    model='gemini-2.5-flash',
    contents='why is the sky blue?',
)
print(response)

Java

CountTokensResponse モジュールと ComputeTokensResponse モジュールをインポートします。

import com.google.genai.types.CountTokensResponse;
import com.google.genai.types.ComputeTokensResponse;

countTokens を使用して、プロンプトに使用されたトークン数をカウントします。

CountTokensResponse response =
  client.models.countTokens("gemini-2.5-flash", "What is your name?", null);

プロンプトがトークン化される方法をより詳細に分析するには、computeTokens を使用します。

ComputeTokensResponse response =
  client.models.computeTokens("gemini-2.5-flash", "What is your name?", null);

完全な実装については、CountTokens.java をご覧ください。

JavaScript

const response = await ai.models.countTokens({
  model: 'gemini-2.5-flash',
  contents: 'The quick brown fox jumps over the lazy dog.',
});

Go

import (
  "context"
  "flag"
  "fmt"
  "log"

  "google.golang.org/genai"
)

client, err := genai.NewClient(ctx, &genai.ClientConfig{Backend: genai.BackendVertexAI})

fmt.Println("Count tokens example.")
countTokensResult, err := client.Models.CountTokens(ctx, *model, genai.Text("What is your name?"), nil)

fmt.Println(countTokensResult.TotalTokens)