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v2026.1714 entries · CC-BY 4.0
Dictionary termTrack AStablev2026.2

Retrieval-augmented generation (RAG)

An AI architecture in which an LLM is augmented at inference time with documents retrieved from an external corpus (often via vector similarity search), so that the model's outputs are grounded in retrieved evidence rather than relying solely on parametric knowledge.

ByCASRAI Editorial Board
· Last updated 21 May 2026

Examples

Worked examples

  • Is an instance

    A research assistant that retrieves PubMed abstracts via vector search and feeds them to GPT-4 to answer a clinical question

Counter-examples

Looks similar, but isn't

  • Not an instance

    A plain LLM that answers from its training corpus without retrieving any external documents is not RAG

Editorial commentary

RAG reduces but does not eliminate hallucination: the model can still misquote retrieved passages or invent content not in them. For scholarly use, disclosure should include the underlying LLM, the retrieval corpus, the embedding model, and the retrieval parameters (top-k, similarity threshold).

References

  • Lewis et al. 2020 ‘Retrieval-Augmented Generation’ NeurIPS
  • Gao et al. 2023 ‘Retrieval-Augmented Generation for LLMs: A Survey’ arXiv

Also known as

RAG · Retrieval-augmented LLM

Machine-readable encodings

Use in your systems

JATS XML <role> element
xml
<role vocab="credit"
      vocab-identifier="https://casrai.org/dictionary/"
      vocab-term="Retrieval-augmented generation (RAG)"
      vocab-term-identifier="https://casrai.org/dictionary/term/retrieval-augmented-generation" />
Schema.org DefinedTerm (JSON-LD)
json
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Adopted by research universities worldwide

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