TreeRAG: Retrieval Procedure

① a tree, no traversal→② score-based, both ways→③ LLM-guided instead→④ traversal learned→⑤ multimodal
0 · intent check LLM, once per query "does it ask to list or summarize?" yes no · skip the traversal entirely: the initial top-K chunks go straight to the reader 1 · initial retrieval (top-K) root § A § B chunk chunk hit ★ chunk embeddings hit leaf chunks each chunk was embedded with its ancestor-title prefix (from BUILD) 2 · up one hop → 3 · all its leaves root ✗ no higher § A § B chunk chunk hit ★ sibling stops at the immediate parent collects every leaf beneath it repeated for each of the K hits · no iteration 4 · re-rank → final chunk set hit chunk ★ sibling chunk sibling chunk leaf chunks only, re-ranked parents · summaries never returned → handed to the reader a single pass, no iteration: each hit gets one hop up + one leaf expansion, then re-rank and stop · nothing is revisited
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