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RAG vs MCP Made Simple: Expanding vs Structuring AI Knowledge

When building AI systems, two concepts often come up and sometimes get confused: RAG (Retrieval-Augmented Generation) and MCP (Model Context Protocol).

They solve different problems but usually work best together.

What RAG does

  • Expands your model’s knowledge beyond training data.
  • Pulls information from external sources like docs, databases, or private data.
  • Great for reducing hallucinations and keeping answers grounded in facts.

Example: Asking a model about your company’s internal policies, RAG lets it fetch the right info from your docs.

What MCP does

  • Structures the interaction layer of your AI.
  • Defines how messages, memory, and metadata are passed.
  • Makes AI systems more modular, consistent, and easier to scale.

Example: Instead of just dumping data into a prompt, MCP organizes how tools, memory, and state interact across sessions.

How they fit together

  • RAG expands what your model knows.
  • MCP organizes how that knowledge is delivered.

Used together, they create AI systems that are both knowledgeable and structured.

Watch our short breakdown here: RAG vs MCP Explained Super Easy!

We usually share short-form content on AI engineering and dev tools on YouTube :)

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