The unreasonable effectiveness of BM25 for agentic search — Jo Kristian Bergum, Hornet.dev
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AI Engineer
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AI Engineer
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Terms in this piece · Glossary
benchmark — A standard public test set for comparing AI models — the shared scoreboards behind every "model X beats model Y" claim.
context window — The maximum amount of text a model can consider at once — its working memory for the current conversation or task.
AI agent — An AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.
Why it matters
It's hard evidence that better query formulation and retrieval, not bigger models, is what limits agentic search accuracy today, and that classic lexical search is far from obsolete for AI agentAn AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.Full definition →-issued queries.
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