Where RAG adds the most value

RAG delivers clear value in applications where three conditions hold: the answers must be grounded in specific documents rather than general knowledge, the document corpus is too large to fit in a single context window, and accuracy on domain-specific facts matters more than fluency on general topics. Enterprise knowledge management — letting employees ask questions answered in internal documentation, policies, and procedures — is the canonical use case. Legal and compliance research, where answers must be traceable to specific regulations and case references, benefits from RAG's ability to cite source material. Technical product support, where answers must match the actual behavior of a specific product version rather than general technical knowledge, is another high-value application.

RAG in customer-facing applications

Customer support applications use RAG to answer questions about specific products, services, and policies by retrieving from support documentation rather than relying on the model's general knowledge. The grounding reduces hallucination — a common failure mode in customer service AI where plausible-sounding incorrect answers create customer harm. Medical and healthcare information services use RAG to anchor responses in vetted clinical guidelines, reducing the risk of confidently stated but inaccurate medical information. Financial services applications use RAG to ground responses in current product terms, regulatory guidance, and company policy.

Where RAG is the wrong tool

RAG works poorly when the answer requires synthesizing across the entire corpus rather than retrieving specific passages — questions like 'what are the three most important themes across all these documents' require a different architecture. It also struggles with questions that require reasoning rather than retrieval: a question that needs logical inference across multiple retrieved facts is better handled by an agent architecture that can iterate over retrieved information. And RAG is unnecessary for applications where the model's general training knowledge is sufficient — adding a retrieval layer increases latency and cost without benefit when the model already knows the answer reliably.