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Youtu-GraphRAG

Youtu-GraphRAG: Vertically Unified Agents for Graph

Retrieval-Augmented Complex Reasoning

Junnan Dong1†, Siyu An1†‡, Yifei Yu1, Qian-Wen Zhang1, Linhao Luo2,
Xiao Huang3, Yunsheng Wu1, Di Yin1,Xing Sun1

1Tencent Youtu Lab
2Monash University
3The Hong Kong Polytechnic University

Graph retrieval-augmented generation (GraphRAG) has effectively enhanced large language models
in complex reasoning by organizing fragmented knowledge into explicitly structured graphs. Prior
efforts have been made to improve either graph construction or graph retrieval in isolation, yielding
suboptimal performance, especially when domain shifts occur. In this paper, we propose a vertically
unified agentic paradigm, Youtu-GraphRAG, to jointly connect the entire framework as an intricate
integration. Specifically, (i) a seed graph schema is introduced to bound the automatic extraction
agent with targeted entity types, relations and attribute types, also continuously expanded for
scalability over unseen domains; (ii) To obtain higher-level knowledge upon the schema, we develop
novel dually-perceived community detection, fusing structural topology with subgraph semantics
for comprehensive knowledge organization. This naturally yields a hierarchical knowledge tree that
supports both top-down filtering and bottom-up reasoning with community summaries; (iii) An
agentic retriever is designed to interpret the same graph schema to transform complex queries into
tractable and parallel sub-queries. It iteratively performs reflection for more advanced reasoning; (iv)
To alleviate the knowledge leaking problem in pre-trained LLM, we propose a tailored anonymous
dataset and a novel ‘Anonymity Reversion’ task that deeply measures the real performance of the
GraphRAG frameworks. Extensive experiments across six challenging benchmarks demonstrate
the robustness of Youtu-GraphRAG, remarkably moving the Pareto frontier with up to 90.71% saving
of token costs and 16.62% higher accuracy over state-of-the-art baselines. The results indicate our
adaptability, allowing seamless domain transfer with minimal intervention on schema.

Code: https://github.com/TencentCloudADP/Youtu-GraphRAG
Data: https://huggingface.co/datasets/Youtu-Graph/AnonyRAG

1 Introduction

Graph retrieval-augmented generation (GraphRAG) has emerged as a promising paradigm to enhance large
language models (LLMs) with structured knowledge [Xiao et al., 2025, Pan et al., 2024], particularly for
complex multi-hop reasoning tasks across multiple documents[Wang et al., 2024, Zhang et al., 2024]. By
representing fragmented documents as connected graphs with underlying relations [He et al., 2024, Dong
et al., 2023], GraphRAG enables LLMs to traverse explicit paths among documents and entities, performing
complex reasoning that is otherwise infeasible within flat retrieval [Peng et al., 2024, Han et al., 2024]. The
structured approach effectively addresses critical limitations in conventional RAG ([Dong et al., 2024]), which
often struggles with the coherent relations between discrete pieces of information and multi-hop reasoning.

† Equal contribution. hansonjdong@tencent.com, siyuan@tencent.com
‡ Corresponding author.

1

Youtu-GraphRAG

The evolution of GraphRAG brings two distinct but equally important trajectories since the foundational
work of [Edge et al., 2024]. First, from the retrieval front, LightRAG [Guo et al., 2024] pioneered vector
sparsification to improve efficiency. While GNN-RAG and GFM-RAG ([Mavromatis and Karypis, 2024, Luo
et al., 2025]) advanced this direction further by incorporating graph neural networks for fine-grained node
matching, more recent HippoRAG 1&2 [Jimenez Gutierrez et al., 2024, Gutiérrez et al., 2025] introduced
memory and personalized PageRank algorithms for context-
aware retrieval. Second, in terms of graph construction, existing
methods can be broadly categorized into flat and hierarchical
approaches. Early methods, such as KGP [Wang et al., 2024],
rely on existing hyperlinks or KNN-based graphs, resulting in
coarse-grained relations that fail to capture nuanced hierarchical
semantics. More recent advancements, such as GraphRAG [Edge
et al., 2024], combine knowledge graphs with community detec-
tion and summarization for multi-level information. Followed
by hierarchical methods like RAPTOR [Sarthi et al., 2024] and
E2GraphRAG [Zhao et al., 2025], they further refine the graph
using tree-like clustering and recursive summarization to enrich
structural representation. However, they remain constrained by
their isolated optimizations, concentrating on either construction
or retrieval while neglecting their interdependencies. This po-
tentially limits complex reasoning performance where cohesive
knowledge organization and retrieval are equally important.

Figure 1. A sketched comparison among
existing pipelines and Youtu-GraphRAG.
represents a non-tailored component, indicat-
ing current methods focus on either graph
construction (a) or retrieval (b) in isolation,
while Youtu-GraphRAG proposes a unified
paradigm (c) for superior complex reasoning.

To bridge this gap, we aim to answer a critical question:
How can we effectively unify graph construction and retrieval
for more robust complex reasoning?

This task is challenging for two reasons. First, construction and retrieval are not readily aligned as two distinct
components. It remains difficult to organically establish synergy between them, where the constructed graph
could effectively benefit retrieval with both structures and semantics. Second, how to properly evaluate the
performance remains a tough problem. With the rapid scaling of LLMs, almost all the existing datasets have
already been ‘seen’ before. This fails to reflect the real performance of the entire GraphRAG.

In this paper, we propose a vertically unified agentic paradigm, Youtu-GraphRAG, to jointly consider both
graph construction and retrieval as an intricate integration based on graph schema. To be specific, (i) a
graph schema is introduced to bound the extraction agent that ensures the quality and conciseness with
targeted entity types, relations and attribute types; The seed schema is continuously and automatically
expanded based on the feedback. (ii) To obtain higher-level knowledge upon the schema, we develop dually-
perceived community detection, fusing structural topology with subgraph semantics for comprehensive
knowledge clustering. This naturally yields a hierarchical knowledge tree that supports both top-down
filtering and bottom-up reasoning with community summaries; (iii) An agentic retriever is designed to
interpret the same graph schema to transform complex queries into parallel sub-queries and perform iterative
reflection. The agent iteratively performs both reasoning and reflection for more advanced performance;
(iv) To alleviate the knowledge leaking problem in pre-trained LLM, we first propose a tailored anonymous
dataset with an ‘Anonymity Reversion’ task. Extensive experiments across six challenging benchmarks
demonstrate the robustness of Youtu-GraphRAG, remarkably moving the Pareto frontier with up to 90.71%
saving of token consumption and 16.62% higher accuracy over SOTA baselines. The results also indicate our
remarkable adaptability which allows seamless domain transfer with minimal intervention on the graph
schema, providing insights of the next evolutionary GraphRAG paradigm for real-world applications.

Contributions. In general, our primary contributions are summarized hereunder:

• We first propose a vertically unified Agentic GraphRAG framework to integrate graph construction and
retrieval for more robust and advanced reasoning, where both construction and retrieval agents are
bounded by graph schema for effective extraction and query decomposition, respectively;

• A novel theoretically-grounded community detection algorithm is employed to inject high-level sum-

2

(a)(b)(c)RetrievalGraphConstructionLLMLLMLLMGraphConstructionDocumentsRetrievalQueryQueryGraphConstructionRetrievalIndexingYoutu-GraphRAG

Figure 2. A toy overview of Youtu-GraphRAG that unifies graph construction and retrieval through a schema-guided
agentic paradigm. (i) An extraction agent automatically processes documents into structured knowledge via targeted
entity/relation extraction; (ii) A four-level knowledge tree is constructed upon the schema with a community detection
that fuses topological structures and graph semantics, enabling hierarchical reasoning; (iii) A retrieval agent decomposes
user queries into parallel sub-queries aligned with the schema, iteratively driving multi-route retrieval.

marization upon graph schema, simultaneously preserving structural and semantic graph properties;

• We present a tailored anonymous dataset and ‘Anonymous Revertion’ task is proposed to prevent LLM

knowledge leaking for fair evaluation of the GraphRAG performance;

• Extensive empirical experiments are conducted over five challenging benchmarks, showing state-of-the-art
performance across diverse reasoning tasks and domains that moves the Pareto frontier with up to 90.71%
saving of token costs and 16.62% higher accuracy.

2 Task Definition

In this section, we formally define the general GraphRAG pipeline with standardized notations from scratch,
including both graph construction and graph retrieval. We denote scalars as lowercase alphabets (e.g., a),
vectors as boldface lowercase alphabets (e.g., a), matrices as boldface uppercase alphabets (e.g., A) and
copperplate for a set of elements (e.g., A). We refer to GraphRAG as the task of answering a natural language
question by first retrieving structured knowledge from a corpus and then generating a response.

Given a set of documents D, GraphRAG first leverages a frozen LLM fLLM(·) to extract important knowledge,
connected by a structured graph G as output. To enrich the understanding of G, a community detection
algorithm fcomm(G) is employed to partition G into communities C = {C1, C2 . . . Cm} to obtain higher-level
summarizations. Based on the constructed graph G, given a complex query q ∈ Q, a retrieval model
fretrieve(q, G) = arg max P (Gsub | q) traverses the graph and retrieves top-k question-specific subgraphs
Gsub ⊆ G that maximize the similarity with given query q. The final performance is evaluated from multiple
aspects: (i) graph construction costs including time efficiency and token consumptions; (ii) retrieval accuracy
and efficiency; and (iii) final answer accuracy comparing apred and ground-truths agold.

2.1 Construction Stage

Beginning with the documents D as corpus, contemporary GraphRAG research includes two synergistic
knowledge organizations that form the graph G at different granularities. First, the fine-grained graph
Gtriple = (E , R, D) is constructed by using fLLM(D) to extract atomic units in the form of triples (h, r, t) from
each document d ∈ D, where entities {h, t} ∈ E and relations r ∈ R are explicitly linked to represent the
abundant relational information among them. The extraction is performed by the frozen LLM fLLM(d),
which processes raw text to populate Gtriple with schema-compliant triples. Concurrently in another pipeline
of research, a coarse-grained document graph Gdoc = (D, C) is built by directly clustering documents to
maximally preserve the raw context where the atomic units are documents instead of triples. To obtain
higher-level knowledge, a complementary community detection algorithm fcomm(G) is employed. Typically,
fcomm(G), including Louvain, Leiden, GMM [Traag et al., 2019, Sarthi et al., 2024], etc., operates over G with

3

ExtractionAgentKnowledgeTreeConstructionRetrievalAgentDocumentsDecompositionUserQueryLLMPlanningFour-LevelKnowledgeTree📦GraphSchema/│─ Entity type│─ Relation└ Attribute TypeSeedGraphSchemasufficient summaries and abstracts generated by fLLM(d), and results in communities C = {C1, C2 . . . Cm}.
Ci ⊆ G is further summarized into a high-level meta-node ˆei = fLLM(Ci) by fLLM(C) where ˆei ∈ G. The
performance is evaluated by the time used tconstruct and the token consumptions $ during construction.

2.2 Retrieval Stage

Youtu-GraphRAG

During inference, given a query q ∈ Q, the typical retrieval model fretrieve(q, G) = arg max P (d | q) directly
returns the top-k similar documents ˆD = {d1, d2 · · · dk} as the final answer, while graph-based methods
provide a more explainable subgraph ˆG for multi-hop path traversal, i.e., fretrieve(q, G) = arg max P ( ˆG | q)
rk−→ ek} ∈ G. Based on the retrieved subgraph, fLLM(q, ˆG) is employed to
where ˆG = {e0
generate the final answer. The final performance is evaluated holistically by the retrieval recall comparing
ˆGdoc and ground truth documents Adoc

gold and answer accuracy by comparing between apred and agold.

r2−→ · · ·

r1−→ e1

3 Approach: Youtu-GraphRAG

In this section, we elaborate on the core methodology of Youtu-GraphRAG, designed to answer two funda-
mental research questions: (i) How to achieve unified optimization of graph construction and retrieval
for higher robustness and generalizability? (ii) How could we enable effective reasoning across different
knowledge granularities? Correspondingly, our framework integrates three designs in a vertically unified
manner based on graph schema. First, a graph schema-bounded agent is designed to ensure construction
quality while eliminating noise through automatic expansion. Second, beyond the schema, we present a
dual-perception community detection that jointly analyzes both topological and semantic similarity to create
multi-scale knowledge clusters which forms a four-level knowledge tree. Finally, an agentic retriever is
designed to effectively decompose questions into schema-aligned atomic sub-queries with parallel retrieval
routes and iterative reflection.

3.1 Schema-Bounded Agentic Extraction

Existing GraphRAG methods leverage either pure LLMs or OpenIE ([Jimenez Gutierrez et al., 2024, Gutiérrez
et al., 2025, Luo et al., 2025, Edge et al., 2024]) for named entity recognition and triple extraction. However,
this open-ended approach would inevitably introduce noise and irrelevant trivia, thereby reducing the
usability of the graph. Instead, we treat graph extraction as constrained generation based on a high-quality
seed graph schema for domain-specific tasks and define a compact schema as

S ≜ (cid:10)Se, Sr, Sattr

(cid:11),

(1)

where Se indicates the targeted entity types (e.g., Person, Disease), Sr guides the extraction with condensed
relations (e.g., treats, causes), and Sattr lists attribute types that could be attached and used to describe
any corresponding entities (e.g., occupation, gender). A frozen LLM-based agent fLLM(S, D) is bounded to
identify matched information that appear in S, effectively reducing the search space to the Cartesian product
Se × Sr × Sa. Formally, for each document d, we obtain a set of triples hereunder

T (d) = (cid:8) (h, r, t), (e, rattr, eattr) | { f (h), f (t), f (e)} ∈ Se, {r, rattr} ∈ Sr, eattr ∈ Sattr

(cid:9).

(2)

Therefore, in our paper, we define Gtriple = (E , R, D), where the entire entity set E = {Er, Eattr} contains not
only named entities e but also the corresponding attributes eattr and the relation set R similarly contains both
entity-entity relations r and rattr, i.e., has_attribute relations to connect entities and attributes. However,
a seed schema could be general and require manual efforts for predefinitions, which limits the scalability
and adaptability of GraphRAG to unseen domains. We thereby equip the agent with an adding tool

4

Youtu-GraphRAG

Figure 3. An overview of our dually-perceived community detection. (a) Input graph partitioning into initial communi-
ties via triple embeddings; (b) community center identification through joint consideration of topology connectivity and
subgraph semantic similarity; and (c) iterative pairwise community merging to form the final hierarchy. Distinct colors
represent functionally coherent communities.

and incorporate an adaptive design that dynamically refines the initial schema S through continuous
interaction with the document content. The agent automatically proposes schema expansions by analyzing
the underlying relational patterns in each document d ∈ D through the update function:

∆S = ⟨∆Se, ∆Sr, ∆Sattr⟩ = I[ fLLM(d, S) ⊙ S] ≥ µ,

(3)

where S (t) represents the schema at iteration t, µ serves as a confidence threshold to control the acceptance
of new schema elements. ∆S contains candidate expansions for entity types, relations, and attributes,
respectively. This dynamic adaptation enables the schema to evolve beyond its initial definitions while
maintaining controlled growth, as the agent selectively incorporates only high-confidence patterns that
demonstrate sufficient frequency and contextual consistency across documents in the new domain. Therefore,
we expect the resulting schema to maintain its compact representation while gaining document-specific
expressiveness, effectively balancing between strict schema guidance and flexible knowledge acquisition.
Through this mechanism, our framework achieves more comprehensive knowledge coverage compared to
static schema approaches, particularly when processing domains with emerging relational patterns.

3.2 Upon Schema: Graph Indexing with Knowledge Tree

The fine-grained raw graphs could quickly become extremely dense and noisy. Typically, a complementary
community detection algorithm fcomm(G) is employed to summarize the knowledge so as to reorganize the
graph in communities C = {C1, C2 . . . Cm}. Contemporary methods apply Louvain, Leiden, Gaussian Mixture
Models (GMM) ([Traag et al., 2019, Sarthi et al., 2024]), etc., operates over G with sufficient summaries and
abstracts generated by fLLM(d). Ci ⊆ G is further summarized into a high-level meta-node ˆei = fLLM(Ci) by
fLLM(C) where ˆei ∈ G.

However, the performance of existing community detection methods can hardly satisfy the real-world
demands. They primarily rely on structural connectivity while largely neglecting the rich semantic in-
formation embedded in the relational context. As a result, they often produce suboptimal partitions in
real-world knowledge graphs since both topological and semantic coherence are crucial for meaningful
community detection. To address this limitation, we are motivated to propose a novel and revolutionary

5

SparseAdjacencyMatrixStructureSimilarityInput GraphFinal Communities Initial CommunitiesPartitionedbytriple-level clustering[eh, er, et]TripleEmbeddingTriple<->SubgraphSematic SimilarityCommunityCentersBasedonS2DualPerceptionPair-wise Community Fusion…Iteration#1(a)(b)…Iteration#2(c)S2Youtu-GraphRAG

dual-perception community detection framework that simultaneously optimizes for topological connectivity
and semantic similarity through a three-stage optimization process. An illustration is shown in Figure 3. The
final output is compressed into a Knowledge Tree K of depth L that preserves fine-grained facts at the leaves
and coarse summaries at internal nodes. In our paper, we define L = 4, including {Community, Keywords,
Entity-relation Triples, Attributes}.

Entity Representation. Given a graph G = (E , R), we first encode each entity ei ∈ E by harvesting its
contextualized embedding ei ∈ R3d, aggregating the frozen LLM embeddings of all triples within its one-hop
neighborhood Ni. Specifically, for each triple (ei, r, ej) ∈ Ni, we concatenate the embeddings of the head
entity ei, relation rij, and tail entity ej, then average across all neighboring triples:

ei =

1
|Ni|

∑
(ei,r,ej)∈Ni

(cid:2)ei∥rij∥ej

(cid:3).

(4)

To this end, the entity representation could effectively preserve both local structural patterns and semantic
relations, enabling downstream clustering to leverage both signals.

Cluster Initialization. Due to the huge size of real-world graph G, we first reduce the search space by
initializing the communities by applying K-means clustering on the entity embeddings {ei}N
i=1, producing
an initial partition candidates {C (0)
k }, where the superscript denotes the iteration count. While this
1
step provides a coarse grouping, it does not yet account for the interplay between structural and semantic
similarity. The cluster number is limited as k = min
that ensures minimum 10 entities per cluster, η=200 prevents excessive fragmentation. We implement this
with optimized KMeans (n_init=5, random_state=42) to ensure reproducibility.

, where β=10 controls the granularity

max (cid:0)2, ⌊ |E |

, . . . , C (0)

β ⌋(cid:1), η

(cid:16)

(cid:17)

Iterative Community Fusion via Dual-Perception Scoring. First, to refine the initial clusters, we introduce a
dual-perception scoring function ϕ(ei, C (t)
m ) that quantifies the affinity between a node ei and a community
C (t)
m at iteration t. This score combines two considerations. (i) topological connectivity overlap (Sr) that
measures the Jaccard similarity between the relation incident to ei and those in C (t)
m ; (ii) subgraph semantic
similarity (Ss), which computes the cosine similarity between the entities’s embedding FΘ(Ti) and the
community centroid E

[FΘ(Tjk)], where FΘ is a matrix for embedding transformation.

C(t)
m

with

ϕ(ei, Cm) = Sr(ei, Cm)
(cid:125)

(cid:124)

(cid:123)(cid:122)
relational

⊕λ Ss(ei, Cm)
(cid:125)

(cid:123)(cid:122)
semantic

(cid:124)

,

Sr(ei, Cm) =
(cid:16)
Ss(ei, Cm) = ϕ

∥Ψ(ei) ∩ Ψ(Cm)∥2
∥Ψ(ei) ∪ Ψ(Cm)∥2

,
(cid:0)FΘ(Tj)(cid:1)(cid:17)

FΘ(Ti), ∑
j∈Cm

(5)

(6)

,

where Ss denotes the Jaccard similarity matrix computed over the multiset of incident relation types Ψ(·).
Ss(i, j) measures the overlap of relation-specific neighborhoods between nodes i and j.

Leveraging the dual-perception score, at each iteration t, we first locate the most representative centroid
entities for each community, which maximizes its dual-perception affinity score ϕ(ei, Cm) with respect to
the entire community subgraph. We define the center nodes as: i.e., e∗
center = arg max ϕ(ei, Cm), where
ei ∈ Cm,ϕ(ei, Cm) is the dual-perception score as aforementioned, combining both topological relation overlap
Sr(ei, Cm) and semantic similarity Ss(ei, Cm). This selection criterion ensures that the center node not only
exhibits strong structural connectivity within the community, i.e., high Sr but also encapsulates the dominant
semantic characteristics of the subgraph, i.e., high Ss. The resulting center nodes are then employed to serve
as high-quality representatives for their respective communities, facilitating efficient pair-wise community

6

Youtu-GraphRAG

Figure 4. The figure contrasts three query-resolution strategies for a multi-hop question. While embedding matching
retrieves disjointed facts (left) and traditional agents use repetitive templates (right), our agentic decomposer (center)
leverages domain schema to plan efficient sub-queries: (1) compare record label revenues, (2) locate the larger group’s
headquarters, and (3) trace the explorer’s visit—achieving precise, with parallel reasoning and outperforming unstruc-
tured retrieval and template-based agents.

fusion. We then facilitate the pairwise matching between all clusters using their centroid dual-perception
score. Clusters (C (t)
a

b ) are merged if their dual-perception divergence falls below a threshold ϵ:

, C (t)

E[ϕ(ei, C (t)

a )] − E[ϕ(ei, C (t)

b )] < ϵ.

(7)

This design further shrinks the search space from node-community comparison to node-node comparison,
yielding a boosted efficient community detection.

3.2.1 Knowledge Tree

To this end, building upon our schema-bounded extraction framework, we develop a hierarchical knowledge
organization pipeline that transforms raw graphs into a structured Knowledge Tree K. First, the process begins
with our novel dual-perception community detection algorithm, which computes entity-community affinity
through the combined metric, blending topological connectivity overlap with semantic subgraph similarity.
Second, fLLM(Cm) is then applied to generate a brief name and description for the entire community based
on the member names. These community names are treated as community nodes and inserted into the
original graph, connecting with each member entity with the relation member_of. Third, within each detected
community Cm, we identify pivotal keywords by selecting entities maximizing the structural-semantic score
arg maxei∈Cm ϕ(ei, Cm).

The resulting hierarchy, together with the schema, collectively informs the construction of our four-layer
knowledge tree K. The tree maximizes bottom-up semantic coherence at each level, simultaneously preserv-
ing fine-grained reasoning through granular entity-relation/entity-attribute retrieval (L1) and enhancing
high-level community-based filtering (L4). We formally define it as K = (cid:83)4

ℓ=1 Lℓ

7

The headquarter of Vilaiyaadu Mankatha is located in […]. The explorer goes to the restaurant […];Vilaiyaadu Mankatha is located in […];When did the explorer reach the city where the headquarters of the only group larger than Vilaiyaadu Mankatha's record label is located?GraphQWhere is Vilaiyaadu Mankatha's headquarters located?When did the explorer visit this city?DomainSchemaAgentExistingEmbedding-basedSimilarityMatching QueryEmbeddingAgenticGraphQTraditional Agententitytyperelationattributetype📦Schema/│── 📂Entity type│   │── 📂PERSON│   │── 📂…│   └── 📂ORGANIZATION│── 📂Relation/│   │── 📂COMPARED_TO│   │── 📂…│   └── 📂LOCATED_IN└── 📂Attribute Type/│── 📂NAME    │── 📂REVENUE└── 📂TIMEAgentPlanningWhat is the size of Vilaiyaadu Mankatha's record label?Find {HEADQUARTER_OF} all the {ORANIZATION}s related toVilaiyaadu Mankatha. What is the {TIME} of a {PERSON} has {NAME} ‘explorer’ {VISITS} all the {ORGANIZATION}s?RetrieveWhich {ORGANIZATION} owns the {REVENUE} {COMPARED_TO} Vilaiyaadu Mankatha?PlanningLℓ =





{Cm}
{arg max ϕ(vi, Cm)}
{(h, r, t) | h, t ∈ E , r ∈ R}
{(e, has_attr, {etype
attr

: evalue

attr })} ℓ = 1 (Attributes)

Youtu-GraphRAG

ℓ = 4 (Community)
ℓ = 3 (Keywords)
ℓ = 2 (Entity-Relation Triples)

(8)

3.3 Agentic Retriever

Schema-enhanced Query Decomposer. The complexity of multi-hop queries in large-scale knowledge
graphs necessitates an intelligent decomposition mechanism that respects both the explicit schema constraints
and implicit semantic relationships. Our schema-guided decomposition approach provides several key
advantages over traditional methods. First, by leveraging the graph schema S = (Se, Sr, Sattr), where
Se denotes entity types, Sr represents relation types, and Sattr contains attribute definitions, we ensure
that each generated atomic sub-query strictly adheres to valid patterns in the knowledge graph. This
schema-awareness prevents the generation of ill-formed queries that would either fail to return results
or retrieve irrelevant information. For instance, when processing a query like "Which pharmaceutical
companies manufacture diabetes drugs?", the schema guarantees that the "manufacture" relation only
connects companies to drugs, not to other entity types. Second, the schema serves as a semantic framework
that maintains coherence throughout the decomposition process. Consider the query "Where did Turing
Award winners study?" Our method automatically maps "Turing Award winner" to the appropriate entity
type Se : Person with the specific award attribute, while correctly interpreting "study" as an Sr : educated_at.
This semantic precision prevents the common problem of interpretation drift that often occurs in naive
decomposition approaches. Therefore, the final Q = fLLM(q, S) = {q1, q2 . . . qi}, where i is a pre-defined
maximum number for total atomic sub-queries and each qi explicitly targets either: (i) node-level retrieval
(e, has_attr, a), (ii) triple-level matching (h, r, t), or (iii) community-level verification Cm, as determined by
schema elements Se, Sr, and Sattr.

Iterative Reasoning and Reflection. Since reasoning and reflection are two core cognitive capabilities for
the agent, following the standard agent framework of perception-reasoning-action cycles, we formalize our
agent as a tuple A = ⟨S, H, fLLM⟩, where H denotes the agent’s historical memory containing both reasoning
steps and the retrieval results, and the functions fLLM is employed to implement both key operations.

A(t) = fLLM

(cid:0)qt
(cid:124) (cid:123)(cid:122) (cid:125)
Reasoning

, H(t−1)(cid:1)
(cid:124) (cid:123)(cid:122) (cid:125)
Reflection

,

(9)

This process addresses the compositional generalization challenge in complex QA by (i) maintaining explicit
symbolic grounding through S during reasoning steps, and (ii) performing continuous self-monitoring via
reflection to detect and correct reasoning paths. The agent’s operational flow alternates between forward
reasoning with schema-guided query decomposition and retrieval and backward reflection for complex
scenarios, creating a closed-loop framework that progressively converges to optimal solutions.

Multi-Route Retrieval. To handle diverse sub-query types, we implement four parallel retrieval strategies
with distinct optimization objectives:

Entity Matching :

arg max
e∈E

cos(cid:0)e, qi

(cid:1)

Triple Matching :

arg max

(h,r,t)∈G

cos(cid:0)(eh, r, et), qi)(cid:1)
(cid:1)

Community Filtering :

cos(cid:0)eCm , qi
r1−→ e1
In general, the four retrieval paths exhibit distinct specialization patterns: (i) Entity Matching optimally
handles single-hop simple queries requiring precise node identification, e.g., atomic fact check problem;

DFS Path Traversal : P (qi) = e0

s.t. ∀ri ∈ R, n ≤ d

r2−→ · · · rn−→ en

arg max
Cm∈K

(10)

8

(ii) Triple Matching dominates few-hop reasoning tasks by modeling (h, r, t) compositional semantics,
particularly effective for relationship inference; (iii) Community Filtering aims to address global queries, e.g.,
summarization and cross-domain problems through top-down filtering in the cluster; (4) DFS Path Traversal
scales to complex multi-constraint problems, we define the maximum depth d = 5. This specialization aligns
with the cognitive spectrum from atomic facts to complex reasoning scenarios.

Youtu-GraphRAG

4 Experiments

4.1 Evaluation Metrics

Following the workflow of RAG, the evaluation is typically divided into two stages: (i) assess the accuracy of
retrieved evidence and (ii) examine the end-to-end performance by evaluating the quality of LLMs responses
generated from the retrieved evidence. In practical deployment scenarios, where multiple valid retrieval
references may exist for identical answers, the latter evaluation paradigm has emerged as the prevailing
standard in practical applications.

Regarding the assessment of LLMs responses, several character-based matching protocols, e.g., recall, EM
and F1 score were established. To account for semantic deviations caused by minor character variations,
where slight textual differences may lead to substantially divergent meanings, we employ DeepSeek-V3-0324
to assess response similarity against ground truth references.

During the reproduction of various GraphRAG frameworks, we observed experimental results exhibit
significant variations depending on the prompts in the LLMs generation stage. Specifically, some frame-
works(Zhao et al. [2025]) instruct to explicitly reject to answer when retrieved evidence is insufficient, while
others(Xiao et al. [2025], Sarthi et al. [2024]) allow LLMs to leverage its parametric knowledge or ambiguates
the instruction in such cases. Given that most LLMs have been exposed to extensive corpora during pre-
training, we identify answering questions based on LLMs’ knowledge rather than retrieval mechanism as a
critical factor for fairly evaluation - we term knowledge leaking.

To separately assess two critical capabilities: (1) recognizing knowledge limitations, and (2) leveraging LLMs’
parametric knowledge, we therefore implement a dual-mode evaluation on three widely-used datasets:

• Reject mode. Under this mode, LLMs must reject to answer the question when retrieval fails to provide

sufficient evidence. This strictly evaluates the retrieval effectiveness and prevent hallucination.

• Open mode. LLMs are allowed to answer using either retrieved content or its inherently parametric

knowledge. This maximally measures the overall capability in real-world practical deployment.

We have reproduced representative baselines and conducted comprehensive evaluations based on the
metrics in this work. The corresponding prompts are provided in Appendix A. Moreover, the observations
further underscore the importance of our proposed AnonyRAG dataset to ensure fair and comprehensive
assessment of GraphRAG methods.

4.2 Datasets

We firstly evaluate Youtu-GraphRAG in dual-mode on three widely used multi-hop QA datasets: HotpotQA
(Yang et al. [2018]), MuSiQue (Trivedi et al. [2022]) and 2WikiMultiHopQA (abbreviated as 2Wiki Ho et al.
[2020]), following the setting in (Jimenez Gutierrez et al. [2024], Gutiérrez et al. [2025]) for fair comparison.

To evaluate the framework’s performance across diverse domains, we also employ GraphRAG-Bench(Xiao
et al. [2025]), shorted as G-Bench, a benchmark dataset constructed from textbook corpora. Additionally, to

9

Youtu-GraphRAG

prevent knowledge leaking, we propose two novel bilingual anonymous datasets, i.e., AnonyRAG-CHS
and AnonyRAG-ENG and propose a challenging ‘Anonymous Reversion’ task.

We anonymize specific entity types (e.g., people, locations) in the dataset to break the model’s memory
shortcuts and prevent it from relying on pretrained knowledge rather than retrieved evidence. Moreover, we
preserve semantic coherence through entity linking, enabling LLMs to maintain discourse comprehension
despite anonymized mentions. The construction details of the dataset are documented in Appendix B.

4.3 Baselines

We include three pipelines of research as baselines. (i) Naive RAG, as the standard RAG approach that
retrieves top-k document chunks using vector similarity search without any explicit knowledge structuring;
(ii) Pure GraphRAG, which builds flat knowledge graphs for retrieval but lacks hierarchical organization,
focusing primarily on relational reasoning through graph traversal algorithms, including GraphRAG (Edge
et al. [2024]), LightRAG (Guo et al. [2024]), G-Retriever (He et al. [2024]) and HippoRAG 1&2 (Jimenez Gutier-
rez et al. [2024], Gutiérrez et al. [2025]); (iii) Tree-based GraphRAG, represents hierarchical methods that
employ recursive clustering and summarization to construct multi-level knowledge trees including RAPTOR
(Sarthi et al. [2024]) and E2GraphRAG (Zhao et al. [2025]).

To ensure a fair performance comparison, we reproduce all the baselines and Youtu-GraphRAG with the same
setting and evaluate with consistent metrics. In terms of base models, we maintain DeepSeek-V3-0324 and
Qwen3-32B as the base LLMs and a lightweight embedding model all-MiniLM-L6-v2.

4.4 Overall Evaluation

4.4.1 Comparison of Time and Token Consumption

For baselines involving graph construction and community detection stages, this section compares their
token and time consumption. Unless otherwise specified, all LLM APIs invoked here are based on the
DeepSeek-V3-0324 and deployed on identical hardware. All procedures are executed using 32-thread
concurrent inference to ensure both the efficiency of graph construction and the fairness of comparisons.

Figure 5a presents the time and token consumption during the graph construction stage for Youtu-GraphRAG
and five baselines. Our method consistently achieves the lowest token consumption across all six datasets
and maintains relatively efficient time performance on five of the datasets. In the community detection
stage, as shown in Figure 5b, Youtu-GraphRAG achieves the lowest token consumption compared with the
other three baselines, consuming no more than 10,000 tokens on any dataset. Meanwhile, our method also
demonstrates consistently efficient time performance across all datasets.

(a) Consumption comparison of graph construction

(b) Consumption comparison of community detection

10

Youtu-GraphRAG

Table 1. Overall performance comparisons over benchmark datasets in terms of top-20 Accuracy.

Method

HotpotQA

2Wiki

MuSiQue

G-Bench Annoy-CHS Annoy-ENG

Open

Reject Open

Reject Open

Reject

Open

Open

Open

Zero-shot LLM

53.70

-

Naive RAG

79.90

72.40

E2GraphRAG
RAPTOR

LightRAG
GraphRAG
G-Retriever
HippoRAG
HippoRAG-IRCOT
HippoRAG2

Ours w/o Agent
Youtu-GraphRAG

68.70
80.90

71.90
56.10
49.00
81.70
81.00
81.80

83.70
86.50

48.80
73.60

56.00
26.40
6.70
73.10
74.60
74.90

75.30
81.20

41.6

70.3

43.20
70.10

58.00
41.80
35.80
77.90
78.40
77.30

72.80
85.50

Deepseek-V3-0324

-

25.7

-

38.9

47.49

30.63

20.00
38.40

29.20
10.00
5.00
64.00
66.00
48.30

57.80
77.60

28.36
48.50

38.98
32.20
23.50
48.30
46.70
50.80

51.40
53.60

8.01
31.10

24.57
16.50
1.70
36.20
35.50
37.80

40.00
47.50

Qwen3-32B

Zero-shot LLM

36.40

-

33.30

-

13.40

-

Naive RAG

75.00

69.00

58.50

39.60

40.64

33.03

RAPTOR

79.20

72.90

61.20

40.10

38.99

32.86

HippoRAG
HippoRAG-IRCOT
HippoRAG2

Ours w/o Agent
Youtu-GraphRAG

77.00
80.30
81.80

83.80
85.90

71.80
76.60
71.30

73.90
78.60

72.80
74.80
65.20

74.90
85.70

62.50
65.40
39.90

55.30
74.20

40.60
44.70
51.40

52.90
54.60

32.10
37.40
37.70

40.10
45.30

70.92

71.81

68.66
73.08

70.83
75.54
70.63
72.89
73.38
79.37

81.53
86.54

70.04

72.69

72.20

75.64
77.11
80.35

80.74
84.48

9.62

12.5

16.01
12.08

9.16
21.66
4.07
36.77
36.05
12.92

37.06
42.88

5.11

7.56

13.37

8.58
9. 16
12.65

34.88
39.24

8.18

43.02

35.97
40.2

22.14
38.85
5.08
40.68
42.17
43.16

40.05
43.26

6.49

26.84

22.14

32.30
33.15
38.36

35.13
40.05

4.4.2 Main Performance Comparison

In Table 1, we report the top-20 accuracy across six challenging benchmarks under both open and reject
modes, based on two strong LLM backbones, i.e., DeepSeek-V3-0324 and Qwen3-32b. Across virtually all
datasets and settings, Youtu-GraphRAG attains the highest performance, reflecting its ability to combine
precise retrieval with robust reasoning. Besides, we also include an variant with no agent for iterative
reasoning and reflection as a lightweight version, i.e., Ours w/o Agent, fulfilling real-world applications
requiring real-time interactive feedback.

The distinction between the two evaluation modes provides complementary perspectives on system capa-
bility. Open mode unlocks the full reasoning potential of the LLM to synthesize an answer regardless of
retrieval gaps. This mirrors high-coverage real-world deployments where maximizing end-task accuracy
outweighs caution. Youtu-GraphRAG consistently outperforms existing baselines, achieving improvements
from 2 to 8 points over the strongest competitor across datasets. When augmented with our agent framework,
Youtu-GraphRAG further pushes the performance frontier, reaching top-20 accuracies of 86.5%, 85.5%, and
53.6% on HotpotQA, 2Wiki, and MuSiQue respectively under Deepseek-V3-0324, and 85.9%, 85.7%, and
54.6% under Qwen3-32B, demonstrating a clear advantage in multi-hop reasoning and cross-document
synthesis. Reject mode, by contrast, imposes a stringent criterion if the retrieved context is insufficient, the
model must abstain. Youtu-GraphRAG attains 81.2%, 77.6%, and 47.5% on HotpotQA, 2Wiki, and MuSiQue,
outperforming the strongest baseline by 7–14 points. Across all datasets, our method achieves consistently
higher top-20 accuracy, confirming its ability to synergize graph-based retrieval with agent-driven reasoning
for both high-coverage and high-precision scenarios. We value this metric since it directly probes retrieval
quality, as speculative answers are penalized and the acceptance rate becomes a direct function of retrieval
completeness and precision. Our superiority on two anonymous datasets also validates the generalizability
of Youtu-GraphRAG beyond standard benchmarks. Specifically, under the open mode, it achieves 42.88%

11

Youtu-GraphRAG

and 43.26% top-20 accuracy on Annoy-CHS and Annoy-ENG, respectively, surpassing all baselines by a
clear margin. These results also reflect our robust reasoning and retrieval integration across diverse lan-
guages and domains, demonstrating that our approach could be easily transferred to previously unseen data
distributions while maintaining high accuracy.

A key objective of Youtu-GraphRAG is to jointly optimize performance and efficiency by unifying graph con-
struction and retrieval. Figure 6 illustrates the trade-off between token consumption during the construction
and overall QA performance across six benchmarks. Our approach consistently achieves optimal perfor-
mance with the least token consumption, effectively shifting the Pareto frontier compared to all baselines.

While existing GraphRAG methods face a dilemma
to balance the token consumption during con-
struction and the accuracy for final generation,
Youtu-GraphRAG leverages a vertically unified novel
framework, i.e., schema-guided extraction, dually-
perceived community detection and the schema-
enhanced agentic retrieval to build concise yet se-
mantically rich graphs and allow the agent to max-
imize reasoning effectiveness. As a result, our
Figure 6. Youtu-GraphRAG effectively moves the Pareto fron-
method effectively moves the Pareto frontier and at-
tier with lower token costs and higher performance.
tains the best performance on all benchmarks while consuming up to an order of magnitude fewer tokens
during graph construction. This demonstrates that careful integration of structured schema alignment,
hierarchical knowledge tree, and adaptive retrieval can fundamentally improve the cost-effectiveness of
GraphRAG systems in real-world applications.

Table 2. Overall performance comparisons over benchmark datasets based on DeepSeek in terms of top-10 Accuracy.

Method

HotpotQA

2Wiki

MuSiQue

G-Bench Annoy-CHS Annoy-ENG

Open

Reject Open

Reject Open

Reject

Open

Open

Naive RAG

79.40

68.00

67.60

33.70

45.58

26.73

RAPTOR

78.20

67.10

67.40

36.40

45.88

30.03

G-Retriever
LightRAG
GraphRAG
HippoRAG
HippoRAG-IRCOT
HippoRAG2

Ours w/o Agent
Youtu-GraphRAG

49.90
71.98
54.30
78.20
78.10
79.40

80.50
83.40

5.90
58.10
23.70
69.40
70.20
70.40

72.10
78.90

38.00
65.70
40.00
77.10
77.70
74.60

72.10
82.30

3.80
38.10
9.80
61.10
60.70
45.80

54.40
72.60

23.50
39.40
30.20
45.20
44.40
49.10

49.80
52.10

1.70
22.90
16.00
30.90
31.60
34.00

38.30
46.90

71.22

72.79

70.24
69.74
61.39
70.14
72.89
77.21

80.55
83.50

12.08

11.77

5.38
8.58
21.37
34.01
36.19
13.52

35.17
38.08

Open

38.93

33.99

5.50
18.90
38.36
40.12
41.42
37.24

40.54
42.57

4.5 Analysis of Generalizability

To examine the domain-transfer capability of Youtu-GraphRAG, we evaluate it across six heterogeneous
benchmarks without any task-specific fine-tuning. As shown in Figure 7, Youtu-GraphRAG achieves the
best performance in both Open Accuracy and Reject Accuracy on all datasets, surpassing state-of-the-art
GraphRAG baselines by a clear margin.

We attribute this strong generalizability to the intrinsic integration of graph construction and retrieval within
our framework. (i) The schema-guided extraction agent produces consistent, domain-adaptive graphs;
the dually-perceived community detection yields hierarchical knowledge structures that remain robust
across domains; (ii) The agentic query decomposer dynamically adapts retrieval strategies to different
question types without manual tuning. Notably, our model demonstrates particularly large gains on multi-

12

1M8M32M64M128MToken Consumption020406080Performance (%)HotpotQA2WikiMuSiQueGraphRAG-Bench AnonyRAG-CHSAnonyRAG-ENGLightRAGLGraphRAGHippoRAG1-IR_COTHippoRAG2Youtu-GraphRAGYoutu-GraphRAG

Table 3. Ablation studies of our method over six datasets. We evaluate three variants: without Community detection
(w/o Comm.), without Agent coordination (w/o Agent), and without Schema guidance (w/o Schema).

Variants

HotptQA 2Wiki MuSiQue G-Bench AnonyRAG-CHS AnonyRAG-ENG

w/o Comm.
w/o Agent
w/o Schema
Youtu-GraphRAG

79.50
75.30
77.10
81.20

75.10
57.80
73.40
77.60

44.00
40.00
45.60
47.50

85.02
81.53
83.50
86.54

39.97
37.60
35.61
42.88

39.92
40.05
40.32
43.26

hop reasoning datasets such as HotpotQA and 2Wiki in open settings, and shows superior abstention
capability on MuSiQue and 2Wiki in reject settings, indicating robustness in both complex reasoning and
uncertainty calibration. These results confirm that Youtu-GraphRAG can seamlessly transfer to unseen
domains while preserving structural fidelity and reasoning depth, fulfilling the vision of a foundational
GraphRAG paradigm.

Furthermore, we summarize the top-10 results in
Table 2, which provides a more stringent evaluation
of retrieval. Our methods consistently outperform
all baselines across both open and reject modes. In
the open mode, Youtu-GraphRAG achieves top-10 ac-
curacies of 83.4%, 82.3%, and 52.1% on HotpotQA,
2Wiki, and MuSiQue respectively, surpassing the
strongest competitor by 4˜8 points. Under the reject
mode, the gains are even more pronounced, with
improvements of 8˜12 points, indicating robust re-
trieval fidelity and reduced speculative answering.
Notably, on the two anonymous datasets, Annoy-
Figure 7. We showcase the generalizability over six bench-
CHS and Annoy-ENG, our agent-enhanced model
mark datasets in terms of both open and reject accuracy.
attains 38.08% and 42.57%, reinforcing its consistent superiority in diverse scenarios. These top-k results
confirm that our approach not only excels in high-coverage settings but also maintains precise answer
selection under stricter evaluation criteria, further validating the effectiveness of integrating graph-based
retrieval with agent-guided reasoning.

4.6 Ablation Studies

To quantify the contribution of each component, we perform ablations by removing community detection
(w/o Comm.), agent reasoning and reflection (w/o Agent), and schema guidance (w/o Schema). Results on
six benchmarks are summarized in Table 3.

Specifically, removing community detection leads to a consistent drop across all datasets, particularly
on multi-hop QA tasks such as HotpotQA and 2Wiki around 1.7% and 2.5%, indicating that structuring
knowledge into coherent communities facilitates more accurate retrieval and reasoning for global questions.
The absence of agent reasoning and reflection causes the most severe degradation on complex reasoning
datasets, especially on 2Wiki and MuSiQue with remarkable 19.8% and-7.5% differences, supporting our
motivation that the iterative reasoning-feedback loop plays an essential role for resolving ambiguous
intermediate steps. Eliminating schema guidance results in noticeable performance drops on knowledge-
intensive settings, especially on AnonyRAG-CHS with 7.27% decreases, highlighting the importance of a
high-quality initialization of seed schema for new domains. This further demonstrates our advantage since
Youtu-GraphRAG only requires minimum manual intervention to handle with domain shifts. In conclusion,
our model consistently outperforms all ablated variants, demonstrating that the three components are
complementary: community detection improves retrieval quality, agent reasoning enhances multi-step

13

20406080100HotpotQA2WikiMuSiQueGraphRAG-BenchAnonyRAG-CHSAnonyRAG-ENGOpen Acc. (%)RAPTORLGraphRAGHippoRAG1HippoRAG2Youtu-GraphRAG20406080MuSiQueHotpotQA2WikiReject Acc. (%)RAPTORLGraphRAGHippoRAG1HippoRAG2Youtu-GraphRAGYoutu-GraphRAG

inference, and schema guidance enforces structural fidelity. These findings suggest that removing any single
component disrupts the synergy between retrieval and reasoning, with agent reasoning being most critical
for multi-hop inference, while schema plays a vito role in low-resource and domain-specific scenarios.

5 Related Work

While large language models (LLMs) demonstrate remarkable capabilities in language understanding
and reasoning, they are known to be prone to hallucinations—generating confident yet factually incorrect
outputs—especially when reasoning over complex or multi-hop queries [Zhang et al., 2025, Qin et al., 2024,
Kuang et al., 2025, Dong et al., 2024, Qin et al., 2024]. Integrating LLMs with graph-structured knowledge,
therefore, combines the generative flexibility of LLMs with the factual rigor of structured data, enabling
more accurate and trustworthy reasoning over complex domains [Luo et al., 2023, Dong et al., 2023, Bei
et al., 2025, Yasunaga et al., 2021, Luo et al., 2024]. Evolving development of GraphRAG has progressed
along two complementary research trajectories since the seminal work of [Edge et al., 2024]. The first
following approaches have evolved from LightRAG’s [Guo et al., 2024] vector sparsification techniques
to more sophisticated graph-aware methods. Subsequent innovations include GNN-RAG and GFM-RAG
[Mavromatis and Karypis, 2024, Luo et al., 2025], which employ graph neural networks for enhanced node
matching, and HippoRAG 1&2 [Jimenez Gutierrez et al., 2024, Gutiérrez et al., 2025] that introduced memory
mechanisms and personalized PageRank algorithms for context-aware retrieval. While another Group
of methods have focused on improving the quality of knowledge organization, hierarchical approaches
like RAPTOR [Sarthi et al., 2024] and E2GraphRAG [Zhao et al., 2025] employ tree-like clustering and
recursive summarization to enhance semantic organization. However, current research remain constrained
by their specialized optimizations, either focusing on retrieval or construction in isolation, and lack a unified
design. This fragmentation limits their performance on complex reasoning tasks requiring tight integration of
knowledge organization and retrieval capabilities, which makes it even harder to adjust the entire framework
for generalizability especially when domain shifts occur. Our work bridges this gap by developing a holistic
framework that jointly optimizes both aspects while maintaining graph foundation model properties.

6 Conclusions

In this paper, we propose Youtu-GraphRAG, a vertically unified agentic paradigm that jointly optimizes both
aspects through a graph schema. Our framework introduces (i) a schema-guided agent for continuous
knowledge extraction with predefined entity types, relations, and attributes; (ii) dually-perceived commu-
nity and keyword detection, fusing structural topology with subgraph semantics to construct a hierarchical
knowledge tree that supports top-down filtering and bottom-up reasoning; (iii) an agentic retriever inter-
prets the schema to break complex queries into tractable sub-queries, paired with an iterative reasoning
and reflection; and (iv) Anonymity Reversion, a novel task to mitigate knowledge leakage in LLMs, deeply
measuring the real performance of GraphRAG frameworks supported by a carefully curated anonymous
dataset. Extensive experiments across six challenging benchmarks demonstrate Youtu-GraphRAG’s robust-
ness, advancing the Pareto frontier with up to 90.71% reduction in token costs and 16.62% higher accuracy
than state-of-the-art baselines. Notably, our framework exhibits strong adaptability, enabling seamless
domain transfer with minimal schema adjustments. These results underscore the importance of unified
graph construction and retrieval, paving the way for more efficient and generalizable GraphRAG.

14

Youtu-GraphRAG

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10.48550/ARXIV.2405.12819. URL https://doi.org/10.48550/arXiv.2405.12819.

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Youtu-GraphRAG

A Prompt templates in LLMs generation

We present the prompt templates in A.1 and A.1, which designed to evaluate whether permitting LLMs to
utilize its parametric knowledge within the RAG system affects performance. To minimize confounding
factors, we employed minimalistic prompts that solely differentiate between the two modes.

A.1 Reject mode

Given the question and the extracted knowledge from different retrieval paths, please answer the
question below. If the extracted knowledge is not enough to answer, please reject to answer.

Question: {query}

Extracted Knowledge: {context}

Answer:

A.2 Open mode

Given the question and the extracted knowledge from different retrieval paths, please answer the
question below. If the extracted knowledge is not enough to answer, please answer it based on your
own knowledge.

Question: {query}

Extracted Knowledge: {context}

Answer:

B Data Collection and Processing

All raw data in this study are sourced from the original texts of four classic novels: Water Margin, Dream of
the Red Chamber, Moby-Dick, and Middlemarch. The copyrights of all these works have entered the public
domain, thus presenting no copyright issues. In selecting data sources, we pursued two key objectives: (1)
Ensuring comprehensive multilingual evaluation coverage, while (2) Maintaining sufficient complexity in
entity representations (e.g., persons, locations) to rigorously assess model capabilities. The basic statistical
information of the dataset is in Table 4.

In our data processing methodology, we employed DeepSeek for entity extraction from the corpus, then
the data chunks are anonymized with the extracted entities. Query-answer pairs were constructed by
DeepSeek using queries from 2Wiki and MuSiQue as seed templates. Upon acquiring the question-answer
pairs, we performed entity anonymization using the same anonymization dictionary as applied to the
corpus. This procedure ensures that LLMs cannot effectively leverage parametric memorized patterns from

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questions. A representative example of anonymized question-answer pairs is presented in Table 5. As
clearly demonstrated, while LLMs could handle questions according to common sense knowledge, their
performance significantly degrades when confronted with anonymized versions of these questions. This
phenomenon forces LLMs to rely on retrieved contextual information rather than depending solely on their
parametric knowledge.

To avoid the variance in evaluating subjective questions, we finally converted the questions into two formats:

Anonymity Reversion. We provide LLMs with anonymized question-answer pairs as context, requiring to
infer and reconstruct the original entities that were anonymized. This task specifically assesses the model’s
ability to leverage contextual clues for entity recovery.

Multiple Choice. To diversify question types and ensure objective evaluation, a subset of questions was
converted into multiple-choice format.

We then performed zero-shot filtering to verify model performance on these transformed questions. This de-
sign preserves the original assessment objectives of testing the LLM’s contextual reasoning capabilities while
guaranteeing answer objectivity and uniqueness. Crucially, it mitigates potential unreliability introduced by
LLM-as-judge evaluation paradigms. Table 6 presents representative cases of these two question formats.

Table 4. Question Type and Difficulty Distribution Statistics

Question Type

Difficulty Level

Chinese Literature

English Literature

Water Margin Dream of Red Chamber Moby-Dick Middlemarch

Objective

Simple (≤4 hops)
Complex (>4 hops)

Subjective
(Anonymous Reversion)

Simple (≤4 hops)
Complex (>4 hops)

Total

29
24

65
146

264

26
34

50
314

424

54
51

51
142

298

54
22

116
219

411

Total

163
131

282
821

1397

Table 5. Comparations of anonymized and Non-anonymized questions

Lang

Type

Question

Zero-shot LLM Response

CHS

ENG

Raw
Query

Annoy
Query

Raw
Query

Annoy
Query

Val

Correct

Wrong

从史进拜师到最终离开少华山，
期间共经历了哪些身份转变？

从富家子弟→王进徒弟→庄主→强盗同伙→落草为
寇，共经历四次身份转变。

从[PERSON#277]拜师到最终离
开[LOCATION#759]，期间共经
历了哪些身份转变？

从拜师到离开[LOCATION#759]，[PERSON#277]的
关键身份转变可梳理如下：1. 入门弟子阶段, 初始以
普通学徒身份拜入师门，主要承担基础杂役工作. . .

What does the narrator’s reac-
tion to Queequeg’s smoking in
bed reveal about their relation-
ship?

The narrator’s acceptance of Queequeg’s smoking re-
veals their deepening friendship and shared comfort.

Correct

What does the [PERSON#1999]’s
reaction to [PERSON#200]’s
smoking in bed reveal about
their relationship?

To analyze what [PERSON#1999]’s reaction to [PER-
SON#200]’s smoking in bed reveals about their re-
lationship, we would need more context about the
specific reaction and. . .

Wrong

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Lang

Question

Ground Truth

Table 6. Final Question-Answer Formats

CHS

ENG

Anonymity Reversion

请根据上下文对下面这段问答
‘‘‘
Q: 在[PERSON#532]离开[LOCATION#526]后，他在哪个村庄
的酒店中与[PERSON#277]重逢？这个村庄附近的山上盘踞着
哪两位头领？
A: [PERSON#532]在[LOCATION#110]附近的酒店与[PERSON
#277]重逢，该村庄附近的[LOCATION#535]上盘踞[PERSON#
503]和[PERSON#4]两位头领。
‘‘‘

中已经被匿名化处理的所有人名和地名等进行推理，判断出被
匿名的原本内容是哪些。

Please read the following QA pairs
‘‘‘
Q: What does [PERSON#200]’s story about the wedding feast
reveal about cultural misunderstandings?
A: The story reveals how cultural misunderstandings, such as
[PERSON#588] mistaking the punchbowl for a finger-glass, can
arise from ignorance of local customs.
‘‘‘

then for all anonymized Persons and Locations, perform infer-
ence to determine the original content that was anonymized.

海棠诗社成立时，[PERSON#315]给自己取的别号是什么？这个
别号与她居住的哪个场所相关？

Multiple Choice

CHS

A. [LOCATION#340]；[LOCATION#625]老农
B. [LOCATION#340]；[LOCATION#340]隐士
C. [LOCATION#625]老农；[LOCATION#340]
D. [LOCATION#340]居士；[LOCATION#625]老农

Which two physical traits do [PERSON#1035] and her daughter
[PERSON#445] share in common?

ENG

A. Straight hair and round faces
B. Curly hair and square faces
C. Wavy hair and oval faces
D. Short hair and triangular faces

PERSON#532——鲁智深
PERSON#277——史进
PERSON #4——周通
PERSON#503——李忠
LOCATION#526——五台山
LOCATION#110——桃花村
LOCATION#535——桃花山

PERSON#200——Queequeg
PERSON#588——captai

C. (李纨，稻香老农，稻香村)

B. (Mrs. Garth, daughter Mary)

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