Source · paper

Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks

Author
Lewis et al. (Facebook AI Research)
Published
22 May 2020
Added
4 October 2026
Original
https://arxiv.org/abs/2005.11401

Summary

Names and formalises retrieval-augmented generation: a generator model conditioned on passages fetched from an external index by a learned retriever. It beat purely parametric models on open-domain question answering and produced more factual text.

Key points

  • Splits knowledge into parametric (model weights) and non-parametric (a document index).
  • The index can be updated without retraining the model.
  • Retrieved passages give a natural way to show provenance.

Why it matters

Origin of the term "RAG" and of the design used, in simplified form, by most document-grounded LLM applications.