Get started with Genkit JS

This guide shows you how to get started with Genkit in a Node.js app.

Prerequisites

This guide assumes that you’re familiar with building applications with Node.js.

To complete this quickstart, make sure that your development environment meets the following requirements:

• Node.js v20+
• npm

Install Genkit dependencies

Install the following Genkit dependencies to use Genkit in your project:

• genkit provides Genkit core capabilities.
• @genkit-ai/googleai provides access to the Google AI Gemini models.

npm install genkit @genkit-ai/googleai

Configure your model API key

For this guide, we’ll show you how to use the Gemini API which provides a generous free tier and does not require a credit card to get started. To use the Gemini API, you’ll need an API key. If you don’t already have one, create a key in Google AI Studio.

Get an API key from Google AI Studio.

After you’ve created an API key, set the GEMINI_API_KEY environment variable to your key:

export GEMINI_API_KEY=<your API key>

Note

While this tutorial uses the Gemini API from AI Studio, Genkit supports a wide variety of model providers including Gemini from Vertex AI, Anthropic’s Claude 3 models and Llama 3.1 through the Vertex AI Model Garden, open source models through Ollama, and several other community-supported providers like OpenAI and Cohere. See Models supported by Genkit for details.

Make your first request

Get started with Genkit in just a few lines of simple code.

// import the Genkit and Google AI plugin libraries
import { googleAI } from '@genkit-ai/googleai';
import { genkit } from 'genkit';

// configure a Genkit instance
const ai = genkit({
  plugins: [googleAI()],
  model: googleAI.model('gemini-2.5-flash'), // set default model
});

async function main() {
  // make a generation request
  const { text } = await ai.generate('Hello, Gemini!');
  console.log(text);
}

main();

Next steps

Now that you’re set up to make model requests with Genkit, learn how to use more Genkit capabilities to build your AI-powered apps and workflows. To get started with additional Genkit capabilities, see the following guides:

• Developer tools: Learn how to set up and use Genkit’s CLI and developer UI to help you locally test and debug your app.
• Generating content: Learn how to use Genkit’s unified generation API to generate text and structured data from any supported model.
• Creating flows: Learn how to use special Genkit functions, called flows, that provide end-to-end observability for workflows and rich debugging from Genkit tooling.
• Managing prompts: Learn how Genkit helps you manage your prompts and configuration together as code.
• Integrating in an app: Walk through a deployed example of multiple Genkit flows powering a web app.