Saved Queries And Query Templates With Reusability

via “query expansion and reformulation for improved retrieval”

LangChain reference RAG implementation from scratch.

Unique: Implements query expansion using LLM-based rewriting that generates semantically equivalent query variants (e.g., 'What is X?' → 'Explain X', 'How does X work?', 'Define X'), and merges results from all variants to improve recall without requiring manual expansion rules.

vs others: More flexible than fixed expansion rules because LLM-based rewriting adapts to query content; more practical than single-query retrieval because it captures multiple valid interpretations of ambiguous queries.