P3D — Vector Search Hybrid Boost — Design Report

Date: 2026-05-11 Author: Opus 4.7

Status Fields

phase_status=PASS
mode=DESIGN_AND_PROMPT_ONLY
implementation_allowed=false
root_cause=SEARCH_RANKING_NO_PATH_TITLE_BOOST_NOT_VECTOR_FRESHNESS
no_mutation_performed=true
next_required_action=GPT_REVIEW_IMPLEMENTATION_PROMPT
pack1_paused=true

Deliverables

#	Output	Path	Status
1	Design (10 sections A–J)	design/p3d-vector-search-hybrid-path-title-boost-design.md	✅ Rev 1
2	Implementation Prompt	prompts/p3d-vector-search-hybrid-path-title-boost-implementation-prompt.md	✅ Rev 1 DRAFT
3	Report (this file)	reports/p3d-vector-search-hybrid-path-title-boost-design-report.md	✅

Top 7 Design Decisions

1. App-layer rerank only — no Qdrant mutation, no reindex
2. Boost formula: combined_score = vector_score + path_boost(0.30) + basename_boost(0.20) + title_boost(0.15) + tag_boost(0.15) + path_dir_boost(0.10)
3. Token overlap threshold: ≥50% for basename/title match, any match for tags/path_dir
4. Feature flag: SEARCH_RERANK_ENABLED=true env var — instant rollback
5. Patch point: after Qdrant dedup, before return (single function insertion)
6. No NLP dependency — simple regex tokenizer on whitespace/hyphens/underscores
7. Debug fields: _boost and _original_score added to results for transparency

Acceptance Tests

#	Query	Expected	Baseline rank	Target rank
T1	GPT Review P3D Step 1...	≤2	5	≤2
T2	p3d-pack1-readonly-inventory-prompt rev 2	=1	3	=1
T3	gpt-directive-agent-run-step1...	=1	1	=1
T4	p3d-agent-vector-search-freshness-audit...	=1	1	=1
T5	vector search freshness root cause	top 5 relevant	OK	OK (no regression)
T6	operating rules SSOT	top 3 relevant	OK	OK (no regression)

GPT/User Implementation Review Required

YES — implementation prompt is DRAFT. Dispatch only after GPT + User explicit approval.

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Design Report | 2026-05-11 | Opus 4.7 | DESIGN_AND_PROMPT_ONLY