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Core ConceptRetrieval / Augmentation Layer

RAG (Retrieval-Augmented Generation)

Industry Definition Set • Entity Resolution Path: /glossary/rag

Quick Answer / TL;DR

An AI technique that enhances LLM responses by retrieving relevant external documents at query time, reducing hallucinations and providing up-to-date information.

Key Takeaways

  • Retrieves relevant documents at query time to augment LLM context.
  • Reduces hallucinations by grounding responses in real data.
  • Common pattern in MCP servers for knowledge base access.
  • Requires an embedding model and a vector or keyword store.
Definitive Statement: An AI technique that enhances LLM responses by retrieving relevant external documents at query time, reducing hallucinations and providing up-to-date information.

Technical Context & Protocol Usage

Detailed Explanation
RAG works by embedding a user's query, searching a knowledge base for similar documents, and feeding those documents as context to the LLM. This grounds the model's response in real data rather than its training cutoff. In MCP, RAG is a common pattern: an MCP server exposes tools or resources that perform retrieval, allowing the client to augment the model's context dynamically.

Format & Payload Metadata

Format: Embedding + vector/keyword search + LLM context injection

Latency: Adds 50-500ms of retrieval latency per query

Real-World Implementation Use Case

An MCP server implements RAG by embedding user questions, searching a company wiki, and returning the top relevant sections as context to the LLM.

M
MCPserver.in Engineering

Platform Team

Published: 2026-07-20
Updated: 2026-07-20

References & Technical Specifications

Cite This Page

MLA Style:

MCPserver.in Engineering. "RAG (Retrieval-Augmented Generation)." MCPserver.in Knowledge Hub, 20 July 2026, mcpserver.in/glossary/rag.