H · Hallucination · hybrid retrieval

Hybrid retrieval

Semantic search + keyword search, combined and reranked. The helpcode default.

In one sentence

Hybrid retrieval combines vector (embedding-based) search with lexical (BM25 or similar) search, then fuses and reranks the results so neither approach loses recall on its own.

When it matters

When the knowledge base contains alphanumeric codes (model numbers, error codes, SKUs) that semantic search struggles to capture — embeddings of "E03" and "error E03" can be far apart.

A real-world example

Industrial pumps, 1,200-page manual. Query "startup noise model P-340": semantic search captures "startup noise" but ignores "P-340"; keyword search captures "P-340" but ignores "startup noise". Hybrid captures both, the reranker orders them, the right answer comes back in 1.4 s.


Curated by helpcode research team · Last reviewed 2026-05-22