AI Agent Hybrid Search 2026

Vector search finds semantically similar results, but may miss exact keyword matches. Hybrid search uses both—if it can't find the person, at least it finds the words.

💡 What You Will Learn

Vector search finds semantically similar results, but may miss exact keyword matches. Hybrid search uses both—if it can't find the person, at least it finds the words.

 → Retrieve
    ├─ BM25/Elasticsearch→ 
    └─ Embedding + → 
       ↓
 →  →  → LLM

# 
keyword_results = bm25_search(query)

# 
vector_results = vector_store.similarity_search(query)

# 
hybrid_results = merge_results(keyword_results, vector_results, alpha=0.3)

Summary

def hybrid_search(query, alpha=0.3):
    # alpha=0: , alpha=1: 
    keyword_results = bm25_search(query)
    vector_results = vector_search(query)

    # 
    combined = {}
    for doc, score in keyword_results:
        combined[doc['id']] = score * alpha
    for doc, score in vector_results:
        combined[doc['id']] = combined.get(doc['id'], 0) + score * (1 - alpha)

    return sorted(combined.items(), key=lambda x: -x[1])[:10]