Gemini MCP Server

# Gemini MCP Server An MCP (Model Context Protocol) server that provides access to Google's Gemini API. Drop-in alternative to Codex MCP with matching interface. ## Features - **gemini** - Start a new Gemini conversation with configurable context - **gemini-reply** - Continue multi-turn conversations - **gemini-image** - Generate images using Nano Banana (Gemini's native image generation) ## Installation ```bash npm install npm run build ``` ## Configuration Create a `.env` file or set environment variables: ```bash # Required: Your Google Gemini API key GEMINI_API_KEY=your_api_key_here # Optional: Override the model (default: gemini-3-pro-preview) GEMINI_MODEL=gemini-3-pro-preview ``` Get your API key from [Google AI Studio](https://aistudio.google.com/apikey). ## Usage with Claude Code Add to your MCP settings (`~/.claude/mcp.json`): ```json { "mcpServers": { "gemini": { "command": "node", "args": ["/path/to/gemini-mcp/dist/index.js"], "env": { "GEMINI_API_KEY": "your_api_key_here" } } } } ``` ## Tools ### gemini Start a new conversation with Gemini. **Parameters:** - `prompt` (required) - The initial prompt - `cwd` - Working directory context - `sandbox` - Access policy: "read-only", "workspace-write", or "danger-full-access" - `base-instructions` - Override default system instructions - `developer-instructions` - Additional context for the model **Returns:** Response text and a `conversationId` for follow-up. ### gemini-reply Continue an existing conversation. **Parameters:** - `conversationId` (required) - ID from a previous gemini call - `prompt` (required) - Your follow-up message ### gemini-image Generate images using Nano Banana, Google's native image generation built into Gemini. **Models:** - **Nano Banana** (`gemini-2.5-flash-image`) - Fast, cost-effective (~$0.04/image), good for most use cases - **Nano Banana Pro** (`gemini-3-pro-image-preview`) - Advanced model with better text rendering, ideal for infographics, diagrams, and text-heavy images **Auto-Detection:** The server automatically uses Nano Banana Pro when your prompt contains keywords like: - "nano banana pro", "pro model" - "infographic", "diagram", "chart", "graph" - "text", "typography", "font", "lettering" - "logo", "brand", "poster", "flyer", "banner" - "slide", "presentation", "document" - "high quality", "4k", "detailed text" **Parameters:** - `prompt` (required) - Description of the image to generate - `numberOfImages` - How many images (1-4, default: 1) - `aspectRatio` - Image ratio: "1:1", "3:4", "4:3", "9:16", "16:9" - `usePro` - Force Nano Banana Pro (auto-detected from prompt if not specified) - `outputPath` - Directory to save generated images **Example:** ``` // Auto-detects Pro model "Create an infographic showing the software development lifecycle" // Explicitly request Pro { "prompt": "A sunset over mountains", "usePro": true } // Fast generation (default) "A cute cat wearing a hat" ``` ## Development ```bash # Run in development mode npm run dev # Build for production npm run build # Start production server npm start ``` ## License MIT