Gemini CLI Provider

The ai-sdk-provider-gemini-cli community provider enables using Google's Gemini models through the @google/gemini-cli-core library. It's useful for developers who want to use their existing Gemini Code Assist subscription or API key authentication.

Version Compatibility

Provider Version	AI SDK Version	NPM Tag	Status
2.x	v6	`latest`	Stable
1.x	v5	`ai-sdk-v5`	Maintenance
0.x	v4	`ai-sdk-v4`	Legacy

# AI SDK v6 (default)
npm install ai-sdk-provider-gemini-cli ai

# AI SDK v5
npm install ai-sdk-provider-gemini-cli@ai-sdk-v5 ai@^5.0.0

# AI SDK v4
npm install ai-sdk-provider-gemini-cli@ai-sdk-v4 ai@^4.0.0

Setup

pnpm add ai-sdk-provider-gemini-cli

Provider Instance

Import createGeminiProvider and create a provider instance with your authentication settings:

import { createGeminiProvider } from 'ai-sdk-provider-gemini-cli';

// OAuth authentication (default if authType omitted)
const gemini = createGeminiProvider({ authType: 'oauth-personal' });

// API key authentication
const gemini = createGeminiProvider({
  authType: 'api-key', // or 'gemini-api-key'
  apiKey: process.env.GEMINI_API_KEY,
});

// Vertex AI authentication
const gemini = createGeminiProvider({
  authType: 'vertex-ai',
  vertexAI: {
    projectId: 'my-project',
    location: 'us-central1',
  },
});

// Google Auth Library
const gemini = createGeminiProvider({
  authType: 'google-auth-library',
  googleAuth: myGoogleAuthInstance,
});

Authentication options:

authType 'oauth' | 'oauth-personal' | 'api-key' | 'gemini-api-key' | 'vertex-ai' | 'google-auth-library' - Optional. Defaults to 'oauth-personal'.
apiKey string - Required for 'api-key' / 'gemini-api-key'.
vertexAI { projectId, location } - Required for 'vertex-ai'.
googleAuth GoogleAuth - Required for 'google-auth-library'.
cacheDir string - Optional directory for OAuth credentials cache.
proxy string - HTTP/HTTPS proxy URL.

Language Models

Create models that call Gemini through the CLI using the provider instance:

const model = gemini('gemini-2.5-pro');

Supported models:

gemini-3-pro-preview: Latest model with enhanced reasoning (supports thinkingLevel)
gemini-3-flash-preview: Fast Gemini 3 model (supports thinkingLevel)
gemini-2.5-pro: Production-ready model with 64K output tokens (supports thinkingBudget)
gemini-2.5-flash: Fast, efficient model with 64K output tokens (supports thinkingBudget)

Example

import { createGeminiProvider } from 'ai-sdk-provider-gemini-cli';
import { generateText } from 'ai';

const gemini = createGeminiProvider({
  authType: 'oauth-personal',
});

const { text } = await generateText({
  model: gemini('gemini-2.5-pro'),
  prompt: 'Write a vegetarian lasagna recipe for 4 people.',
});

Model Settings

const model = gemini('gemini-3-pro-preview', {
  temperature: 0.7,
  topP: 0.95,
  topK: 40,
  maxOutputTokens: 8192,
  thinkingConfig: {
    thinkingLevel: 'medium', // 'low' | 'medium' | 'high' | 'minimal'
  },
  verbose: true, // Enable debug logging
  logger: customLogger, // Custom logger (or false to disable)
});

Model Capabilities

Model	Image Input	Object Generation	Tool Usage	Tool Streaming
`gemini-3-pro-preview`
`gemini-3-flash-preview`
`gemini-2.5-pro`
`gemini-2.5-flash`

Images must be provided as base64-encoded data. Image URLs are not supported.

Authentication

OAuth Authentication (Recommended)

Install and authenticate the Gemini CLI globally:

npm install -g @google/gemini-cli
gemini  # Follow the interactive authentication setup

Then use OAuth authentication in your code with authType: 'oauth-personal'.

API Key Authentication

Generate an API key from Google AI Studio.
Set it as an environment variable: export GEMINI_API_KEY="YOUR_API_KEY"
Use authType: 'api-key' with your key.

Requirements

Node.js 20 or higher
Gemini CLI installed globally for OAuth authentication
Valid Google account or Gemini API key

For more details, see the provider documentation.