Markdown source

The unreasonable effectiveness of BM25 for agentic search

Conference Context

Session Description

GPT-5 is shockingly good at search, and that changes the "BM25 as a baseline" story. Using GPT-5 search trajectories from BrowseComp-Plus, I'll show how default BM25 parameters and evaluation harnesses can make lexical retrieval look weak, while real agent queries often play directly to BM25's strengths. Much like grep became a core retrieval primitive for coding agents, BM25 is re-emerging as a powerful primitive for agentic search.

Media Evidence

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Evidence Graph

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Agent Reading Notes

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Transcript Status

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People

Notes

Synthesis

Synthesized Breakdown

The unreasonable effectiveness of BM25 for agentic search ## Conference Context - Date/time: 2026-06-29 · 11:10am-11:30am - Track/room: Search & Retrieval · Track 3 - Speaker(s): Jo Kristian Bergum - Session type/status: session · confirmed - Track: Search & Retrieval - Room: Track 3 - Session type: session - Status: confirmed ## Session Description GPT-5 is shockingly good at search, and that changes the "BM25 as a baseline" story. Using GPT-5 search trajectories from BrowseComp-Plus, I'll show how default BM25 parameters and evaluation harnesses can make lexical retrieval look weak, while real agent queries often play directly to BM25's strengths. Much like grep became a core retrieval primitive for coding agents, BM25 is re-emerging as a powerful primitive for agentic search. ## Media Evidence No related AI Engineer channel video found yet.

Speaker And Company Context

Topics Covered

Derived Links And Source Material

Novel Concepts / Clever Methods

Evidence Boundary

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