Recognition: 2 theorem links
· Lean TheoremDisco-RAG: Discourse-Aware Retrieval-Augmented Generation
Pith reviewed 2026-05-16 16:04 UTC · model grok-4.3
The pith
Disco-RAG improves RAG by building discourse trees inside chunks and rhetorical graphs across chunks, then feeding both into a planning blueprint that conditions generation.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Disco-RAG constructs intra-chunk discourse trees to capture local hierarchies and builds inter-chunk rhetorical graphs to model cross-passage coherence; these structures are jointly integrated into a planning blueprint that conditions generation, yielding state-of-the-art results on question answering and long-document summarization benchmarks without fine-tuning.
What carries the argument
The planning blueprint that receives intra-chunk discourse trees and inter-chunk rhetorical graphs and uses them to condition the generation step.
If this is right
- Generation quality improves on tasks that require combining facts from multiple retrieved passages.
- Long-document summarization gains coherence because cross-passage relations are explicitly modeled.
- No parameter updates are required to obtain the reported gains.
- The same blueprint can be applied to any retrieval-augmented pipeline that already returns multiple passages.
Where Pith is reading between the lines
- The same discourse-construction step could be inserted into retrieval pipelines for dialogue or multi-hop reasoning without changing the base model.
- If discourse parsers improve, the performance ceiling of Disco-RAG would rise automatically.
- The planning blueprint may also reduce unsupported claims by forcing the model to respect explicit coherence links.
Load-bearing premise
Automatically built discourse trees and rhetorical graphs will correctly reflect the intended hierarchies and coherence relations in the retrieved passages.
What would settle it
An ablation that removes the discourse trees and rhetorical graphs from the planning blueprint and still obtains the same benchmark scores would falsify the claim that discourse injection drives the improvement.
Figures
read the original abstract
Retrieval-Augmented Generation (RAG) has emerged as an important means of enhancing the performance of large language models (LLMs) in knowledge-intensive tasks. However, most existing RAG strategies treat retrieved passages in a flat and unstructured way, which prevents the model from capturing structural cues and constrains its ability to synthesize knowledge from dispersed evidence across documents. To overcome these limitations, we propose Disco-RAG, a discourse-aware framework that explicitly injects discourse signals into the generation process. Our method constructs intra-chunk discourse trees to capture local hierarchies and builds inter-chunk rhetorical graphs to model cross-passage coherence. These structures are jointly integrated into a planning blueprint that conditions the generation. Experiments on question answering and long-document summarization benchmarks show the efficacy of our approach. Disco-RAG achieves state-of-the-art results on the benchmarks without fine-tuning. These findings underscore the important role of discourse structure in advancing RAG systems.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes Disco-RAG, a discourse-aware RAG framework that builds intra-chunk discourse trees to capture local hierarchies and inter-chunk rhetorical graphs to model cross-passage coherence relations; these structures are integrated into a planning blueprint that conditions LLM generation. The central claim is that this yields state-of-the-art performance on question-answering and long-document summarization benchmarks without any fine-tuning.
Significance. If the results are substantiated, the work would provide concrete evidence that explicit discourse modeling can improve evidence synthesis in RAG systems beyond flat concatenation, addressing a recognized limitation in current retrieval-augmented pipelines.
major comments (3)
- [Abstract] Abstract: the claim that Disco-RAG 'achieves state-of-the-art results on the benchmarks without fine-tuning' is presented without any reported numbers, baselines, datasets, or statistical significance tests, rendering the central empirical claim unevaluable.
- [Experiments] Experiments section: no details are supplied on the automatic discourse parser (model, training data, or F1 accuracy on the target domains), nor any error analysis of the resulting trees and graphs; given that standard discourse parsers typically achieve F1 well below 80%, this omission directly undermines attribution of any gains to discourse awareness.
- [Experiments] Experiments section: the manuscript contains no ablation studies that isolate the contribution of the intra-chunk trees, inter-chunk graphs, or planning blueprint versus standard RAG retrieval volume or prompt length, so it is impossible to determine whether the reported improvements are load-bearing on the discourse components.
Simulated Author's Rebuttal
We thank the referee for the thoughtful and constructive review. We agree that the current manuscript requires additional concrete details to substantiate its claims and will revise accordingly. Below we address each major comment point by point.
read point-by-point responses
-
Referee: [Abstract] Abstract: the claim that Disco-RAG 'achieves state-of-the-art results on the benchmarks without fine-tuning' is presented without any reported numbers, baselines, datasets, or statistical significance tests, rendering the central empirical claim unevaluable.
Authors: We agree that the abstract is currently too high-level. In the revised version we will expand it to report specific performance metrics (e.g., exact accuracy/F1 or ROUGE scores), name the datasets and baselines, and note any statistical significance tests performed. This will make the SOTA claim directly verifiable while preserving the abstract's brevity. revision: yes
-
Referee: [Experiments] Experiments section: no details are supplied on the automatic discourse parser (model, training data, or F1 accuracy on the target domains), nor any error analysis of the resulting trees and graphs; given that standard discourse parsers typically achieve F1 well below 80%, this omission directly undermines attribution of any gains to discourse awareness.
Authors: We acknowledge this gap. The revised manuscript will specify the exact discourse parser (model, training corpus such as PDTB or RST-DT), report its F1 scores on the evaluation domains, and add a dedicated error-analysis subsection that quantifies parsing errors and discusses their downstream effect on retrieval and generation quality. revision: yes
-
Referee: [Experiments] Experiments section: the manuscript contains no ablation studies that isolate the contribution of the intra-chunk trees, inter-chunk graphs, or planning blueprint versus standard RAG retrieval volume or prompt length, so it is impossible to determine whether the reported improvements are load-bearing on the discourse components.
Authors: We agree that ablations are essential. The revision will include systematic ablations that (i) disable intra-chunk trees, (ii) disable inter-chunk graphs, and (iii) disable the planning blueprint, each compared against standard RAG baselines that match retrieval volume and prompt length. These experiments will isolate the contribution of the discourse components. revision: yes
Circularity Check
No significant circularity; architectural proposal without self-referential derivations
full rationale
The paper presents Disco-RAG as an empirical architectural framework that builds intra-chunk discourse trees and inter-chunk rhetorical graphs then feeds them into a planning blueprint for conditioning generation. No equations, parameter fittings, or mathematical derivations appear in the provided text that would reduce any claimed prediction or result to the inputs by construction. The central claims rest on benchmark performance rather than on self-definitional steps, fitted inputs renamed as predictions, or load-bearing self-citations that import uniqueness theorems. This matches the default expectation of a non-circular proposal whose validity is testable externally via ablation or parser accuracy metrics.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Discourse structures extracted from text chunks accurately reflect intended hierarchies and cross-passage coherence
Lean theorems connected to this paper
-
IndisputableMonolith/Foundation/AbsoluteFloorClosure.leanreality_from_one_distinction unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
constructs intra-chunk discourse trees to capture local hierarchies and builds inter-chunk rhetorical graphs to model cross-passage coherence... integrated into a planning blueprint
-
IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
RST tree parsing... rhetorical graph construction... discourse-aware plan
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
Works this paper leans on
-
[1]
Better document-level sentiment analysis from RST discourse parsing. InProceedings of the 2015 Conference on Empirical Methods in Natural Lan- guage Processing, pages 2212–2218, Lisbon, Portu- gal. Association for Computational Linguistics. Eric J Bigelow, Ari Holtzman, Hidenori Tanaka, and Tomer Ullman. 2025. Forking paths in neural text generation. InTh...
work page 2015
-
[2]
Chi-Min Chan, Chunpu Xu, Ruibin Yuan, Hongyin Luo, Wei Xue, Yike Guo, and Jie Fu
Evaluating the evaluators: Are readability metrics good measures of readability?arXiv preprint arXiv:2508.19221. Chi-Min Chan, Chunpu Xu, Ruibin Yuan, Hongyin Luo, Wei Xue, Yike Guo, and Jie Fu. 2024. RQ-RAG: Learning to refine queries for retrieval augmented generation. InFirst Conference on Language Model- ing. Chia-Yuan Chang, Zhimeng Jiang, Vineeth Ra...
-
[3]
Akash Gautam, Lukas Lange, and Jannik Strötgen
T-rag: lessons from the llm trenches.arXiv preprint arXiv:2402.07483. Akash Gautam, Lukas Lange, and Jannik Strötgen. 2024. Discourse-aware in-context learning for temporal ex- pression normalization. InProceedings of the 2024 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 2: ...
-
[4]
A Survey of Context Engineering for Large Language Models
SciNews: From scholarly complexities to pub- lic narratives – a dataset for scientific news report generation. InProceedings of the 2024 Joint In- ternational Conference on Computational Linguis- tics, Language Resources and Evaluation (LREC- COLING 2024), pages 14429–14444, Torino, Italia. ELRA and ICCL. Dongqi Liu, Chenxi Whitehouse, Xi Yu, Louis Mahon,...
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[5]
Beyond n-grams: Rethinking evaluation met- rics and strategies for multilingual abstractive summa- rization. InProceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Vol- ume 1: Long Papers), pages 19019–19035, Vienna, Austria. Association for Computational Linguistics. Hellina Hailu Nigatu, Min Li, Maartje Ter Hoeve, Sal...
-
[6]
LLaMA: Open and Efficient Foundation Language Models
RAPTOR: Recursive abstractive processing for tree-organized retrieval. InThe Twelfth Interna- tional Conference on Learning Representations. Ivan Stelmakh, Yi Luan, Bhuwan Dhingra, and Ming- Wei Chang. 2022. ASQA: Factoid questions meet long-form answers. InProceedings of the 2022 Con- ference on Empirical Methods in Natural Language Processing, pages 827...
work page internal anchor Pith review Pith/arXiv arXiv 2022
-
[7]
Qwen3 technical report.arXiv preprint arXiv:2505.09388. Zhenrui Yue, Honglei Zhuang, Aijun Bai, Kai Hui, Rolf Jagerman, Hansi Zeng, Zhen Qin, Dong Wang, Xuan- hui Wang, and Michael Bendersky. 2025. Inference scaling for long-context retrieval augmented genera- tion. InThe Thirteenth International Conference on Learning Representations. Amir Zeldes, Tatsuy...
work page internal anchor Pith review Pith/arXiv arXiv 2025
-
[8]
MoC: Mixtures of text chunking learners for retrieval-augmented generation system. InProceed- ings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Pa- pers), pages 5172–5189, Vienna, Austria. Associa- tion for Computational Linguistics. Xiangrong Zhu, Yuexiang Xie, Yi Liu, Yaliang Li, and Wei Hu. 2025. Knowledge...
work page 2025
-
[9]
When did The Lion King debut on Broadway?
Later, on June 13, 2006, the production moved to the Minskoff Theatre, where it continues to run. Reference Answer. The Lion King opened on Broadway more than once. It premiered on Broadway at the New Amsterdam Theatre in previews on October 15, 1997, then officially opened on Broadway on November 13, 1997. On June 13, 2006, the Broadway production moved ...
work page 2006
-
[10]
RST tree is a hierarchical tree structure (not a graph or network)
-
[11]
Each internal node has exactly two children: one nucleus (core) and one satellite (support) or two nuclei at the same time
-
[12]
The nucleus contains the main information; the satellite provides supporting content
-
[13]
Relations describe how the satellite relates to the nucleus
-
[14]
Think carefully and output ONLY ONE complete RST tree. Allowed RST relations: ELABORATION, EXPLANATION, EVIDENCE, EXAMPLE, CONTRAST, COMPARISON, CONCESSION, ANTITHESIS, CAUSE, RESULT, CONSEQUENCE, PURPOSE, CONDITION, TEMPORAL, SEQUENCE, BACKGROUND, CIRCUMSTANCE, SUMMARY , RESTATE- MENT, EV ALUATION, INTERPRETATION, ATTRIBUTION, DEFINITION, CLASSIFICA- TIO...
-
[15]
Segment text into meaningful elementary discourse unit (EDU)
-
[16]
Determine the most important EDU (this becomes the root nucleus)
-
[17]
For each other EDU, decide: Is it nucleus (core) or satellite (support)?
-
[18]
Assign one relation from the allowed list
-
[19]
Required output format: EDUs: [1]<first EDU> [2]<second EDU>
Build the binary tree bottom-up. Required output format: EDUs: [1]<first EDU> [2]<second EDU> . . . [N]<Nth EDU> RST ANALYSIS: RELATION(EDUi, EDUj): {RELATION TYPE} . . . TREE STRUCTURE: ROOT[1-N] |--- NUCLEUS[X] <EDU text> (N) |--- SATELLITE[Y] <EDU text> (S): {RELATION TYPE} Validation rules: - Each EDU must be complete and meaningful. - Relations must ...
-
[20]
Carefully read all chunks in the list and identify the main claim, fact, or event expressed in each one
-
[21]
Reason about how each chunk relates to the others at the discourse level, taking into account global context across all chunks
-
[22]
For every ordered pair of distinct indices (i, j), decide whether CHUNK[i] serves a discourse function relative toCHUNK[j]
-
[23]
If a rhetorical link exists, assign exactly one relation type from the allowed list. Required output format: For each ordered pair(i, j)withi̸=j, output one line in the following format: CHUNK[i] -> CHUNK[j]: {RELATION_TYPE} List all such lines for all ordered pairs in a consistent order (e.g., sorted byithenj). Validation rules: - Use only the allowed re...
-
[26]
Inter-chunk rhetorical graph, modeling cross-passage discourse flow. Critical instructions:
-
[27]
The plan must be written as a continuous paragraph in natural language
-
[28]
The plan should describe the intended organization of the final answer
-
[29]
The plan must be dynamically adapted to the given user query and evidence
-
[30]
Avoid reproducing the content of the chunks; only outline how they will be used
-
[31]
Output exactly one complete rhetorical plan. Required output format: PLAN:< one paragraph in natural language that describes the planned organization of the answer> TEXT TO ANALYZE:{query, chunks, RST trees, rhetorical graph} Figure 12: Prompt for Discourse-Driven Planning. Prompt for Full Context Generation You are an expert in question answering and tex...
- [32]
-
[34]
Use the full document as the only source of factual claims
-
[35]
If the document does not support a claim, do not add it
-
[36]
Write a coherent answer without copying long spans verbatim from the document. Required output format: ANSWER<one paragraph or multiple paragraphs in natural language> TEXT TO ANALYZE{query, document} Figure 13: Prompt for full context generation used in our baseline. Prompt for Standard RAG You are an expert in retrieval-augmented generation. Your task i...
-
[39]
Use the retrieved chunks as the only source of factual claims
-
[41]
Write a coherent answer without copying long spans verbatim from the chunks. Required output format: ANSWER<one paragraph or multiple paragraphs in natural language> TEXT TO ANALYZE{query, chunks} Figure 14: Prompt for standard RAG used in our baseline. Prompt for Retrieve-and-Plan Baseline You are an expert in retrieval-augmented generation. Your task is...
- [42]
-
[44]
The plan must be grounded in what is supported by the retrieved chunks
-
[47]
Write a coherent answer without copying long spans verbatim from the chunks. Required output format: PLAN<one paragraph plan> ANSWER<one paragraph or multiple paragraphs in natural language> TEXT TO ANALYZE{query, chunks} Figure 15: Prompt for the retrieve-and-plan baseline used in our ablation study. Prompt for Plan-and-Retrieve Baseline You are an exper...
-
[48]
Retrieved text chunks returned after plan-guided retrieval. Critical instructions:
-
[49]
Write the plan as a single continuous paragraph that outlines the structure of the answer
-
[50]
The retrieval hint must be a list of retrieval queries that helps retrieve evidence aligned with the plan
-
[51]
The answer must directly address the user query and use the retrieved chunks as the only source of factual claims
-
[52]
If the retrieved chunks do not support a claim, do not add it
-
[53]
Write a coherent answer without copying long spans verbatim from the chunks. Required output format: PLAN<one paragraph plan> RETRIEVAL HINT<a list of retrieval queries> ANSWER<one paragraph or multiple paragraphs in natural language> TEXT TO ANALYZE{query, chunks} Figure 16: Prompt for the plan-and-retrieve baseline used in our ablation study. Prompt for...
-
[54]
For each ordered pair (i, j) with i̸=j , treat CHUNK[i] as the source and CHUNK[j] as the target
-
[55]
Do not infer implicit relations
Consider only explicit connectives that are supported by the two chunks. Do not infer implicit relations
-
[56]
Output exactly one marker from the marker list if a marker is applicable; otherwise output NONE
-
[57]
Output a decision for every ordered pair withi̸=j. Required output format: For each ordered pair(i, j)withi̸=j, output one line in the following format: CHUNK[i] -> CHUNK[j]: {MARKER} TEXT TO ANALYZE: CHUNK[1]: [first chunk] CHUNK[2]: [second chunk] . . . CHUNK[K]: [K-th chunk] Figure 17: Prompt for discourse marker inference used in the shallow discourse...
-
[58]
Retrieved text chunks
-
[59]
Intra-chunk RST trees, capturing local rhetorical hierarchies
-
[60]
Inter-chunk rhetorical graph, modeling cross-passage discourse flow
-
[61]
A discourse-aware plan that outlines the intended argumentative organization. Critical instructions:
-
[62]
The answer must directly address the user query
-
[63]
Integrate evidence from multiple chunks, guided by their RST trees and rhetorical graph
-
[64]
Follow the discourse-aware plan for structuring the answer
-
[65]
Maintain factual accuracy, logical coherence, and rhetorical clarity
-
[66]
Output a continuous answer in natural language. Required output format: ANSWER:< a single coherent paragraph or multi-paragraph answer grounded in discourse structures> Validation requirements: - The answer must be faithful to the retrieved content. - The answer must be logically organized and reflect discourse-level coherence. - Avoid verbatim repetition...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.