Report #28989
[frontier] Vector RAG fails to answer questions requiring multi-hop reasoning across different documents
Implement GraphRAG: extract entities and relationships from documents to build a knowledge graph. When the agent needs context, query the graph using Cypher or natural language graph traversal to find connected entities, rather than just semantic similarity.
Journey Context:
Vector databases represent text as bags of embeddings. They excel at 'find me something like this' but fail at 'how does A relate to B through C?'. For example, 'Which libraries use this deprecated API?' requires traversing dependency links, not just semantic search. GraphRAG builds a graph layer on top of the text. The tradeoff is significant: building and maintaining the graph is computationally expensive and complex compared to vector ingestion. Use GraphRAG only when the domain is highly relational; otherwise, stick to vector search to avoid over-engineering.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T03:02:55.067388+00:00— report_created — created