Vertex AI plugin for Genkit Dart.

Usage

To use Google's Vertex AI models, simply import this package and pass vertexAI to the Genkit initialization.

Authentication is handled automatically via Application Default Credentials (e.g. gcloud auth application-default login), keeping the implementation clean and avoiding dependencies on dart:io in the core components.

import 'dart:io';

import 'package:genkit/genkit.dart';
import 'package:genkit_vertexai/genkit_vertexai.dart';

void main() async {
  // Initialize Genkit with the Vertex AI plugin
  // Authentication is handled automatically via Application Default Credentials.
  // Project ID and location can be specified explicitly or inferred from the environment.
  final ai = Genkit(
    plugins: [
      vertexAI(
        projectId: Platform.environment['GCLOUD_PROJECT'],
        location: Platform.environment['GCLOUD_LOCATION'] ?? 'us-central1',
      )
    ],
  );

  // Generate text
  final response = await ai.generate(
    model: vertexAI.gemini('gemini-2.5-flash'),
    prompt: 'Tell me a joke about a developer.',
  );

  print(response.text);
}

Embeddings

import 'dart:io';

import 'package:genkit/genkit.dart';
import 'package:genkit_vertexai/genkit_vertexai.dart';

void main() async {
  final ai = Genkit(
    plugins: [
      vertexAI(
        projectId: Platform.environment['GCLOUD_PROJECT'],
        location: Platform.environment['GCLOUD_LOCATION'] ?? 'us-central1',
      )
    ],
  );

  final embeddings = await ai.embedMany(
    embedder: vertexAI.textEmbedding('text-embedding-004'),
    documents: [
      DocumentData(content: [TextPart(text: 'Hello world')]),
      DocumentData(content: [TextPart(text: 'Genkit is awesome')]),
    ],
  );

  print(embeddings[0].embedding);
}