MCP Client Development Guide

Core Mental Model

Host Application (user-facing app like Claude Desktop)
  └─> Creates 1+ MCP Clients (protocol components)
       └─> Each Client connects to exactly 1 Server (1:1 mapping)
            └─> Server exposes Tools/Resources/Prompts
                 └─> LLM decides which to use
                      └─> Client executes, returns results

Key Principle: Client = stateful messenger, NOT decision maker. LLM chooses tools, client facilitates execution.

Development Workflow