Grounding (LLM)
LLM feature: connect responses to external data sources (web search, internal docs, knowledge base) with citations. Reduces hallucinations. Standard: Gemini Grounding, Claude Search, Perplexity, ChatGPT Search.
Two modes: retrieval-augmented (RAG-style — fetch relevant docs, include in context) or search-grounded (live web search per query, cite sources). Gemini Grounding: Google Search integrated, returns inline citations. Claude has a citation mode for internal docs + web search. Perplexity built an entire product around grounding. Trade-offs: latency increase (5-30s for thorough search), quality-depends-on-search-quality, can-be-distracted-by-low-quality-sources. Modern enterprise RAG: hybrid grounding (internal docs + web).