PolyUQuest: Verifiable Structure-Aware Web RAG over Heterogeneous Graphs
Summary
PolyUQuest is a novel, verifiable, structure-aware web Retrieval-Augmented Generation (RAG) framework designed to overcome limitations of existing systems that treat web content as flat text. Developed by researchers at The Hong Kong Polytechnic University, it constructs a heterogeneous graph unifying hyperlink topology, DOM hierarchy, and entity-relation knowledge across web pages. A two-tier router intelligently dispatches queries to one of three retrieval modes: direct block retrieval, cross-page graph traversal, or multi-hop entity reasoning. This system ensures full answer verifiability, providing source page, heading path, and entity links for every cited block. Evaluated on 4,240 PolyU web pages, PolyUQuest achieved superior correctness (0.644), coverage (0.649), and faithfulness (0.921), with a 36-point faithfulness gain over the next-best baseline. It also significantly reduced LLM token consumption to 2,968 tokens per query, demonstrating efficiency. The system is slated for deployment as a student-facing QA service.
Key takeaway
For Machine Learning Engineers developing RAG systems over complex web content, PolyUQuest demonstrates that integrating hyperlink topology, DOM hierarchy, and entity-relation knowledge into a unified heterogeneous graph is crucial. Your team should implement a query routing mechanism to dispatch requests to structure-matched retrieval modes, significantly improving answer correctness, coverage, and faithfulness while reducing LLM token costs. Prioritize verifiable provenance by linking answers directly to source blocks and paths, enhancing user trust and debugging capabilities for institutional or enterprise deployments.
Key insights
PolyUQuest unifies web structure into a heterogeneous graph for verifiable, efficient, and accurate RAG.
Principles
- Unify web structure: hyperlinks, DOM, entities.
- Route queries to structure-matched retrieval modes.
- Provide full provenance for answer verifiability.
Method
PolyUQuest's offline phase builds a three-layer heterogeneous graph from crawled web pages. The online phase routes queries via a two-tier router to structure-aware retrieval modes (direct block, navigation, entity reasoning) for evidence assembly and answer generation.
In practice
- Implement structure-aware RAG for complex websites.
- Enhance QA systems with verifiable answer provenance.
- Optimize LLM token usage via query routing.
Topics
- Retrieval-Augmented Generation
- Heterogeneous Graphs
- Web Structure Analysis
- Query Routing
- Verifiable AI
- Question Answering Systems
Code references
Best for: Research Scientist, AI Engineer, AI Scientist, Machine Learning Engineer, NLP Engineer
Related on AIssential
See Counsel's argued verdicts on the open AI decisions leaders are weighing →
Editorial summary, takeaway, and curation by AIssential. Original article published by cs.AI updates on arXiv.org.