google-genai-typescript

Utilizing @google/genai in TypeScript

This guide provides comprehensive instructions and best practices for integrating the Google Gen AI SDK (@google/genai) into your TypeScript applications. This SDK allows you to build powerful applications leveraging Gemini models, supporting both the Gemini Developer API and Vertex AI.

1. Introduction to @google/genai

The @google/genai SDK is Google DeepMind’s primary SDK for its generative AI offerings, designed for TypeScript and JavaScript developers to build applications powered by Gemini. It is where new AI features are added.

2. Prerequisites

• Node.js: Version 20 or later.

For Vertex AI Users (excluding Vertex AI Studio)

1. Google Cloud Project: Select or create one.
2. Billing: Enable billing for your project.
3. Vertex AI API: Enable the Vertex AI API.
4. Authentication:
   • Install the gcloud CLI.
   • Initialize the gcloud CLI.
   • Create local authentication credentials: gcloud auth application-default login

3. Installation

To install the SDK, use pnpm:

pnpm add @google/genai

4. Initialization

The SDK supports initialization for both Google AI Studio (API Key) and Vertex AI implementations.

4.1. Gemini Developer API (Using an API Key)

For server-side applications, obtain an API key from Google AI Studio and initialize the client:

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

const GEMINI_API_KEY = process.env.GEMINI_API_KEY; // It is recommended to use environment variables for API keys.

const ai = new GoogleGenAI({ apiKey: GEMINI_API_KEY });

Caution: Avoid exposing API keys in client-side code. Use server-side implementations in production.

4.2. Vertex AI

Initialize the client for Vertex AI by specifying your Google Cloud project and location:

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

const PROJECT_ID = process.env.GOOGLE_CLOUD_PROJECT_ID || "your-gcp-project-id";
const LOCATION = process.env.GOOGLE_CLOUD_LOCATION || "us-central1"; // e.g., "us-central1"

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