Programming Tutorials

  You have built a Model Context Protocol (MCP) server. It runs perfectly when integrated into the Claude Desktop app. However, when you attempt to run the MCP Inspector to debug a new tool or resource, you hit a wall. The connection hangs, times out, or immediately disconnects. This is the "Transport Mismatch" problem, and it is the most common hurdle for developers adopting the MCP standard. The issue is rarely your logic; it is almost always how the communication layer (Transport) is configured versus what the Inspector expects. This guide provides a deep technical analysis of why this breaks and details two distinct architectural patterns to fix it. The Root Cause: Transport Layer Mismatch To debug this effectively, we must understand the architecture of the Model Context Protocol. MCP relies on a client-host-server topology that is transport-agnostic. The SDK provides two primary transport mechanisms: StdioServerTransport:  Communicates via Standard Input/Output (stdin/s...

  Connecting an LLM to your local development environment via the Model Context Protocol (MCP) is akin to giving a highly intelligent, yet easily confused intern root access to your laptop. The productivity gains are massive, but the security implications are terrifying. If you are running a default MCP implementation that exposes  fs.write ,  exec_command , or generic API fetchers, you are vulnerable. A single indirect prompt injection—hidden text in a webpage, a comment in a PR, or a malicious PDF—can trick the model into exfiltrating your  .env  file or wiping your database. This guide details how to move beyond basic "human-in-the-loop" confirmations and implement architectural sandboxing for MCP servers using TypeScript and Docker. The Root Cause: The Confused Deputy Problem To secure an MCP server, we must first understand why the vulnerability exists. In cybersecurity, this is known as the  Confused Deputy Problem . The MCP server (the deputy) has le...