SAG2: Embedding-Free Multi-Hop Retrieval with BM25 and JEV

SAG2, an embedding-free multi-hop retrieval architecture built on a single SQLite database, BM25, and JEV contextual evidence decisions, achieved the highest Recall@5 and Recall@10 among compared methods on 1,000-question subsets of MuSiQue, 2WikiMultiHopQA, and HotpotQA, according to the arXiv paper 2610.22588v1. SAG2 posted Recall@10 of 86.62%, 97.43%, and 99.00% on those three benchmarks and 81.10% document Recall@10 over the 511,962-document EnterpriseRAG-Bench corpus. Indexing all 11,656 MuSiQue passages takes 2.36 seconds, produces a 25.87 MiB database, and requires no model calls, eliminating offline embedding computation, LLM-based event-entity extraction, and dedicated database servers.

arXiv:2610.22588v1 Announce Type: new Abstract: Strong multi-hop retrieval should be practical to deploy without expensive corpus preparation or complex database infrastructure. We present SAG2, an embedding-free retrieval architecture built around a single SQLite database, BM25, and contextual evidence decisions from JEV. SAG2 follows the query-time association principle of SAG SQL-Retrieval Augmented Generation , while replacing its event-entity and dense indexes with a lexical index over original passages. Selected passages supply terms for further retrieval, and newly retrieved evidence guides subsequent decisions. This moves semantic evidence selection to query time, eliminating offline embedding computation, LLM-based event-entity extraction, and dedicated database servers. The resulting system combines lightweight preparation with strong retrieval accuracy: on 1,000-question subsets of MuSiQue, 2WikiMultiHopQA, and HotpotQA, SAG2 achieves the highest Recall@5 and Recall@10 among the compared methods, with Recall@10 of 86.62%, 97.43%, and 99.00%. It also reaches 81.10% document Recall@10 over the 511,962-document EnterpriseRAG-Bench corpus. Indexing all 11,656 MuSiQue passages takes 2.36 seconds, produces a 25.87 MiB database, and requires no model calls. SAG2 demonstrates that accurate multi-hop evidence retrieval can be supported by compact, rapidly prepared infrastructure, making it a practical foundation for knowledge retrieval applications.