MP-101 · Module 4

MCP vs Agent Frameworks

3 min read

MCP is a protocol. LangChain, CrewAI, AutoGen, and the Agents SDK are frameworks. The distinction matters because people keep asking "should I use MCP or LangChain?" as if they are alternatives. They are not. A protocol defines how components communicate. A framework defines how components are orchestrated. You use both — the framework orchestrates the agents, and MCP provides the standard interface through which those agents connect to tools and data.

Think of it this way: TCP/IP is a protocol. Django is a framework. Nobody asks "should I use TCP/IP or Django?" because they operate at different layers. MCP standardizes the tool interface layer. Frameworks handle agent logic, memory management, prompt chaining, and orchestration. An agent built with LangChain can use MCP to access a database. An agent built with CrewAI can use MCP to read files. The framework decides what to do. MCP decides how to connect.

Do This

  • Use MCP for the tool integration layer — connecting agents to external systems
  • Use frameworks for orchestration — agent logic, memory, prompt chains, and workflows
  • Evaluate frameworks partly on their MCP support — native MCP integration is a strong signal
  • Build MCP servers for your custom tools so any framework can use them

Avoid This

  • Do not treat MCP and agent frameworks as mutually exclusive choices
  • Do not rebuild tool integrations inside your framework when an MCP server already exists
  • Do not assume a framework's built-in tool connectors are better than MCP servers — they often lag behind
  • Do not wait for your framework to add MCP support — most have it now or are actively shipping it