MCP Gemini Google Search

# CLAUDE.md This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository. ## Development Commands - `npm run build` - Build TypeScript (generates both ESM and CJS) - `npm run dev` - Watch for file changes and rebuild - `npm run start` - Run the built server - `npm run inspect` - Debug with MCP Inspector - `npm run prepublishOnly` - Automatic build before release ## Architecture This project is a Model Context Protocol (MCP) server that provides Google Search functionality using Gemini's built-in Google Search feature. ### Key Components - **src/index.ts**: Main entry point for the MCP server - Uses stdio transport - Registers and handles the `google_search` tool - Environment variable validation is handled in createGoogleSearchAI - **src/tools/google-search.ts**: Google Search implementation - Uses `@google/genai` SDK to access Gemini - Model can be configured via `GEMINI_MODEL` environment variable - Enables the `googleSearch` tool via `ai.models.generateContent` - Extracts grounding metadata from responses to add citation information - Reference implementation: https://github.com/google-gemini/gemini-cli/blob/main/packages/core/src/tools/web-search.ts ### Tech Stack - TypeScript + Node.js 18+ - @google/genai (Google's unified GenAI SDK) - @modelcontextprotocol/sdk - tsup for dual ESM/CJS build ### Type Error Resolution Notes - The `@google/genai` API uses `ai.models.generateContent` - Tools parameter format: `config: { tools: [{ googleSearch: {} }] }` - Response access structure: `response.candidates[0].content.parts` - Grounding metadata is located at `response.candidates[0].groundingMetadata` ### Environment Variables **For Google AI Studio (default):** - `GEMINI_API_KEY`: Google AI Studio API key (required) - `GEMINI_MODEL`: Model to use (optional, default: gemini-2.5-flash) **For Vertex AI:** - `GEMINI_PROVIDER`: Set to "vertex" - `VERTEX_PROJECT_ID`: GCP project ID (required) - `VERTEX_LOCATION`: Region (optional, default: us-central1) - `GEMINI_MODEL`: Model to use (optional, default: gemini-2.5-flash) ## Important Instructions ### Web Search Tool Usage When performing web searches in this repository, use the `mcp__gemini-google-search__google_search` tool provided by this MCP server instead of the default WebSearch tool. This ensures consistency with the project's Google Search implementation using Gemini's built-in search capabilities.