Exa MCP Server is a Model Context Protocol server that connects AI agents to Exa's web search and research capabilities. It provides a standardized interface for agents to perform web searches, fetch webpage content, run multi-step research agents, and access other Exa functionalities. The architecture features clear separation of concerns with API handlers for Vercel deployment, core MCP server logic, tool implementations for each Exa capability, and utility functions for authentication, logging, and error handling. Key entry points include stdio CLI for local usage and Vercel HTTP functions for cloud deployment. The system handles authentication via API keys or OAuth, implements rate limiting for free tier users, and includes mechanisms to prevent API key leakage between requests.