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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Multi-LLM Agents Architecture for Claim Verification</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Giuseppe Fenza</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Domenico Furno</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vincenzo Loia</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pio Pasquale Trotta</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Management and Innovation Systems, University of Salerno</institution>
          ,
          <addr-line>Fisciano (SA), 84084</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>IMT School for Advanced Studies</institution>
          ,
          <addr-line>Lucca (LU), 55100</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The rapid spread of misinformation has made automated claim verification essential, as traditional methods struggle to keep pace. While NLP advancements and Large Language Models as GPT-4 show promise, their limitations, such as outdated knowledge, underscore the need for scalable, domain-independent solutions that integrate external resources. This work introduces a novel multi-agent architectural model designed for claim verification, achieving state-of-the-art performance on the FEVER dataset. The proposed system leverages specialized agents powered by Large Language Models (LLMs), integrated within a modular and scalable twolayered framework comprising a Reasoning Layer and a Decision Layer. Extensive experimentation demonstrates significant performance improvements, with the optimized system achieving 85.31% accuracy and 85.29% F1Macro, outperforming traditional single-model baselines. The study also explores the impact of individual agents' contributions and highlights the efectiveness of reducing system complexity to enhance both accuracy and conclusiveness. These findings establish the potential of multi-agent systems to transform claim verification by ofering robust, and flexible solutions.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Claim Verification</kwd>
        <kwd>Multi-Agents Systems</kwd>
        <kwd>LLM</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The digital era has transformed drastically how information is produced, accessed, and shared, enabling
people to stay constantly connected and updated on current events. However, this technological
revolution has also brought significant challenges because, in this scenario of uncontrolled production of
knowledge, it is becoming more and more dificult to distinguish reliable information from untrustworthy
ones. Indeed, the proliferation of disinformation poses serious threats to public trust, decision-making,
and societal stability. For those reasons and also because traditional methods are not suitable to combat
the rapid spreading of disinformation across various platforms, further improvements to fact-checking
and claim verification processes are crucial. Among the most promising approaches for tackling
disinformation are advancements in automated fact-checking technologies, which leverage Natural
Language Processing and Machine Learning techniques to analyze vast quantities of data and deliver
evaluations of their veracity considering reliable sources, In [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] rely on deep learning techniques to
detect fake news, combining traditional neural networks for classification tasks (e.g., Convolutional
Neural Network, Multi-Layer Perceptron) and pre-trained models (e.g., BERT [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], RoBERTa [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]) to
achieve better performance. For the claim verification task, Pankovska et al. [ 4] use strategies that refer
to textual sources or knowledge bases, allowing them to make informed decisions based on evidence
retrieval results. The previously mentioned solutions are typically trained on specific data, making
them inadequate for use across several domains, highlighting the necessity to develop new scalable and
accurate methods employable for diferent types of domains. Nowadays, thanks to the advancements
in Natural Language Processing, Large Langauge Models (LLMs) have risen, such as GPT-4 [5] and
Gemini 1.5 Pro [6], showing astounding capabilities in comprehending and generating human-like text
and also in performing diferent tasks (e.g., translation, code programming) because of their training on
massive and heterogeneous datasets. However, their knowledge might not be updated, and this could
pose a significant problem for the claim verification task to obtain updated and truthful evaluations
of claims. This problem can be addressed by retrieving additional external knowledge (for example,
exploiting search engines or existing knowledge graphs) to integrate in a prompt to provide to an
LLM or by fine-tuning the LLM to improve its performance for the claim verification task. Current
research focuses mostly on employing a single large language model, which could result in a limited
approach for complex tasks as the claim verification one. In this field and other complex decision-making
processes, the use of multi-agent systems - based on one or more LLMs - could represent a significant
advancement over the traditional reliance on a single, general-purpose large language model. These
systems are designed to mimic the collaborative and specialized eforts of human teams, where each
member contributes unique expertise to address a multifaceted problem efectively [ 7, 8]. Multi-agent
systems enhance precision, scalability, and transparency by assigning specialized tasks to individual
agents, enabling parallel processing and modular adaptability. This approach ensures robust, flexible,
and accountable solutions, particularly in complex domains [9]. This work presents a novel architectural
model for a multi-agent system for claim verification. The model consists of two layers: Reasoning and
Decision layers. The Reasoning layer can comprise multiple agents powered by a large language model
(LLM), each executing distinct tasks and using shared tools. Instead, the Decision layer is composed of
multiple agents responsible for synthesizing other agents’ responses to deliver a well-informed verdict
on the claims veracity. Each agent exploits ReAct [10] and Reflexion [ 11] mechanisms to iteratively
evaluate and adjust the execution plan by incorporating insights from previous actions and observations,
addressing past errors, and enhancing the overall quality of the final outcomes. This robust architectural
model for multi-agent system is designed to address the complexities of claim verification, ofering
scalability and flexibility by enabling the seamless addition of new agents or tasks without disrupting
the overall framework. This adaptability promotes eficiency, precision, and modularity, ensuring the
system remains efective in handling diverse verification challenges. Additionally, the paper details
the optimization process employed to enhance the system’s performance in a binary classification task
using the FEVER dataset, a benchmark that provides a collection of claims paired with corresponding
evidence from Wikipedia. The optimization involved analyzing various configurations, evaluating their
overall performance, and examining the individual contributions of each agent to understand how
they afect the final outcome. This process allowed the achievement of state-of-the-art performance on
the aforementioned benchmark in a binary classification task. This study also addresses key research
questions to explore the strengths and potential of the proposed approach:
• RQ1: How do individual agents’ contributions afect the final outcome?
• RQ2: Does a multi-agent system outperform a single LLM and other baselines on claim verification
using this architectural model?
• RQ3: What is the relation between the number of agents and performance?
      </p>
      <p>The paper continues as follows. Section 2 presents the existing literature about the claim verification
task and the use of LLM agents. The architectural model is described in Section 3. Section 4 shows the
results achieved and outlines the refinement process used to enhance the accuracy of the multi-agent
systems within the proposed architectural model, while also addressing the research questions. Lastly,
Section 5 illustrates the limitation of our approach, while conclusions are presented in Section 6.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Works</title>
      <p>The claim verification problem is often addressed through automated methodologies composed of three
key phases, which can be tackled either individually or collectively [12]: Claim Detection, Evidence
retrieval, and Claim Validation (or Verification .) Frequently, evidence retrieval and claim validation
are combined into a single, integrated task. Additionally, the process of claim validation may include
generating an explanation or justification for the verdict rendered on a claim.</p>
      <p>Claim detection identifies assertions requiring fact-checking. Approaches often fine-tune models
like BERT and T5 [13], integrate meta-features for classification, or verify claims against databases
using ranking methods [14]. Annotated corpora, such as those for climate change [15], support this
task. Evidence retrieval involves finding relevant information to confirm or refute claims, improving
understanding and enabling comparisons with reliable sources. Techniques range from traditional
information retrieval [16] to leveraging search engines [17], knowledge graphs [18, 19], or focusing on
documents published before the claim was made [20]. Claim validation evaluates a claim’s veracity using
methods such as binary classification [ 21], referencing evidence or knowledge bases [4], or employing
graph-based approaches [22]. Lately, various strategies leveraging large language models (LLMs) in
claim verification have been proposed. For example, using perplexity scores from pre-trained language
models on claim-evidence pairs for classification has been explored [ 23]. Alternatively, fine-tuning
LLMs on domain-specific data can improve performance but is resource-intensive [ 24, 25, 19]. Also,
in-context learning [26] demonstrates the efectiveness of few-shot prompting to achieve robust results
without extensive training. With the advancement of LLMs, LLM agents have been utilized in diverse
applications, including solving coding and math problems [8], simulating human behavior [27], and
engaging in debates to address complex challenges [28], often as part of multi-agent systems. As for the
claim verification and fact-checking processes, Li et al [ 29] propose FactAgent, a single fact-checking
agent driven by an LLM and capable of using diferent external tools. Moreover, Zhao et al. [ 30] present a
framework composed of four LLM agents, leveraging LLMs with dynamic planning for claim verification.
This work introduces a scalable and flexible multi-agent architectural model for claim verification,
featuring a Reasoning layer for task-specific analysis by LLM-powered agents and a Decision layer
for synthesizing responses into a verdict, enhanced by iterative ReAct and Reflexion mechanisms to
improve precision and adaptability.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Methodology</title>
      <p>The claim verification process is a multi-step pipeline aimed at determining the veracity of a given
claim by analyzing relevant evidence. This process typically involves tasks such as claim detection,
evidence retrieval, and claim validation. To address the inherent complexities, we propose a
multilayered architecture (Figure 1) that employs agents powered by large language models (LLMs) to ensure
scalability, adaptability, and precision. The system’s agents, tools, and tasks are defined using the
CrewAI framework1. For the underlying large language model, the open-source Gemma2-9B-IT [31] is
utilized. This model, known for its high performance, is accessed and managed through the Ollama
framework2.</p>
      <p>Our architectural model is divided into two distinct layers: Reasoning Layer and Decision Layer, each
playing a specific role in processing and validating claims. The agents’ workflow within the proposed
architectural model and the layers are detailed below.</p>
      <sec id="sec-3-1">
        <title>3.1. Architectural Design &amp; Workflow</title>
        <p>The Reasoning Layer serves as the core analytical component of the proposed architectural model. It
consists of multiple specialized agents, each tasked with a specific role in the claim verification process.
Each agent operates based on its predefined task, guided by a goal-oriented framework and supported by
dedicated tools to perform its function efectively. The agents are designed with backstories that define
their individual focus and operational logic, enabling them to approach tasks with domain-specific
perspectives. Collaboration among agents is facilitated through delegation: when an agent encounters a
need for additional expertise, it can delegate tasks to other agents. The responses from these delegated
agents are then integrated by the delegating agent to complete its own task. This collaborative reasoning</p>
        <sec id="sec-3-1-1">
          <title>1https://www.crewai.com/ 2https://ollama.com/</title>
          <p>is enhanced by ReAct (Reasoning and Acting) and Reflexion mechanisms, which empower the agents to
iteratively refine their thoughts and actions, ensuring robust and adaptable processing of claims.</p>
          <p>The workflow begins with the first agent in the Reasoning Layer, which receives the input claim.
The agent analyzes the claim using its tools and the ReAct and Reflexion mechanisms to generate a
task-specific output. Once this task is completed, the output is passed to the Decision Layer. This
process continues iteratively until all agents in the Reasoning Layer have completed their tasks.</p>
          <p>The Decision Layer comprises multiple Decision Agents, responsible for aggregating and synthesizing
the outputs from the Reasoning Layer. These agents evaluate the coherence of the collected information
and determine the final verdict on whether the claim is supported or refuted. Importantly, the Decision
Agents are intentionally designed without the ability to delegate tasks or utilize tools (Figure 2). This
constraint ensures that the impact of each Reasoning Layer agent on the final verdict is isolated and clear,
avoiding potential biases introduced by further delegation or tool use. The final verdict is determined by
considering the first  consistent outputs from the Decision Agents, where  is a tunable parameter
( ∈ {1, ..., }) and  is the total number of decision agents.</p>
          <p>Decision Agents parameters
Goal: Analyze and synthesize outputs from multiple agents to determine if the claim is supported or
refuted. Label can be SUPPORTS or REFUTES.</p>
          <p>Backstory: A critical thinker with expertise in evidence synthesis and decision-making under uncertainty.
Skilled in integrating multi-agent outputs to reach a comprehensive and unbiased conclusion.
Task: Based on the outputs of Agent 1,..., Agent N, provide a final decision on the claim: CLAIM. The final
decision should be based primarily on factual accuracy.</p>
          <p>Context: Task Output Agent 1,..., Task Output Agent</p>
          <p>Expected Output: A final decision: SUPPORTS or REFUTES the claim.</p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Agents Configuration and Tools</title>
        <p>The initial multi-agent system configuration within the proposed architectural model comprises four
specialized agents in the Reasoning layer, each designed to address distinct aspects of the claim
verification process. These agents are strategically crafted to analyze various key dimensions of claim
validation (Figure 3 shows how each agent is characterized). Their specific goals are outlined below:
• Fact-Checking Agent: Verify the factual accuracy of the claim by identifying verifiable evidence
and providing reliable sources.
• Context Analyst Agent: Analyze the broader context of the claim, such as its historical accuracy,
its alignment with socio-political events, and its cultural significance.
• Media-Bias Analyst Agent: Evaluate potential biases in the claim source and identify patterns
or tones indicative of manipulation or partisanship.</p>
        <p>• Public Sentiment Analyst Agent: Gauge public reaction to the claim.</p>
        <p>Each agent is based on the LLM Gemma2-9B-IT, whose temperature parameter is set to 0.1 for a
more concise output, and equipped with the same tool called _ℎ__, a research
utility that leverages the Google search engine via the Google Custom Search JSON API3. This API
enables the agents to query a Programmable Search Engine4, facilitating eficient information retrieval
for their own task. Additionally, they have the opportunity to delegate to other agents, seeking support
to complete their task. Also, a maximum number of iterations for a task is set to avoid infinite loops
and reduce the time needed to finish the task. However, this could also lead to uncompleted tasks,
resulting in the task output Agent stopped due to iteration limit or time limit. This output is important
as it highlights which agent fails to complete its task, providing insights into its impact on the final
results. It also enables a deeper analysis of each agent’s actions and contributions to the system’s overall
performance. Lastly,  is set to 1 in this setup, meaning the system considers the output of a single
Decision Agent as the final verdict.</p>
        <sec id="sec-3-2-1">
          <title>3https://developers.google.com/custom-search/v1/overview 4https://programmablesearchengine.google.com/controlpanel/create</title>
          <p>The first multi-agent system setup achieves state-of-the-art performance on the FEVER dataset in
a binary classification task compared to other baselines (Table 2), but further experiments have been
carried out.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Experimentation &amp; Results</title>
      <p>This section outlines the various multi-agent systems’ experimental setups derived from the optimization
process conducted to address the previously stated research questions. Additionally, it describes the
dataset used and presents the results obtained for each setup, which are then compared against diferent
baseline models.</p>
      <sec id="sec-4-1">
        <title>4.1. Dataset</title>
        <p>To evaluate the framework, the widely-used Fact Extraction and VERification (FEVER) dataset was
adopted [32]. This dataset is specifically designed for claim verification tasks, where claims are
categorized into three labels: SUPPORTS, REFUTES, and NOT ENOUGH INFO, based on annotations by
human experts. The claims were generated by rephrasing sentences from Wikipedia, and for each claim,
the dataset includes supporting sentences extracted from relevant Wikipedia pages that annotators
used during the labeling process. For this study, the FEVER Development dataset was utilized, but the
evaluation focused on a two-class classification problem, considering only claims labeled as SUPPORTS
or REFUTES, for a total of 13,332 claims, providing a robust foundation for assessing the system’s
performance.</p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. System Optimization and Evaluation</title>
        <p>Although the initial setup demonstrated strong performance, a deeper analysis was undertaken to
explore potential improvements for the Reasoning Layer. This process aimed to answer the first research
question (RQ1): How do individual agents’ contributions afect the final outcome? Table 1
presents the percentage of instances where agents failed to complete their tasks within the iteration
limit, along with their contributions to correct labels and their association with inconclusive answers.</p>
        <p>Agent
Fact-Checking
Context Analyst
Media-Bias Analyst
Public Sentiment Analyst</p>
        <p>Failures (%) Inconclusive (%)</p>
        <p>Contributions (%)
11.82%
8.08%
25.72%
42.35%
18.8%
11.28%
37.59%
91.73%
63.39%
66.07%
54.04%
47.09%</p>
        <p>The columns in Table 1 represent: Failures (%), the percentage of tasks where the agent was unable
to complete its operation within the iteration limit; Inconclusive (%), the percentage of tasks where
the agent was unable to complete its operation within the iteration limit and resulted in an inconclusive
answer; Contributions (%), the percentage of tasks completed by the agent that contributed to a correct
label.
4.2.1. Analysis of Failures and Contributions
As shown in Table 1, the Public Sentiment Analyst and Media-Bias Analyst were the agents most
frequently involved in blocked iterations, with failure rates of 42.35% and 25.72%, respectively. These
agents also contributed significantly to inconclusive answers, accounting for 91.73% and 37.59% of
such cases. Their relatively low contributions to correct labels (47.09% and 54.04%) further highlight
their limited efectiveness. In contrast, the Fact-Checking and Context Analyst agents demonstrated
higher reliability, with failure rates of only 11.82% and 8.08%, respectively, and strong contributions
to correct labels (63.39% and 66.07%). These findings suggest that the outputs of these agents had a
more positive influence on the final outcomes.
4.2.2. Optimization Through System Simplification
Based on this analysis, two optimized setups were tested to improve overall performance: (1)
Multiagent system 2, where the most problematic agent, the Public Sentiment Analyst, was removed; (2)
Multi-agent system 3, where both the Public Sentiment Analyst and the Media-Bias Analyst were
excluded, leaving only the Fact-Checking and Context Analyst agents. Both configurations outperformed
the original system, with Multi-agent system 3 achieving the best results. This demonstrates that
reducing system complexity by removing less efective agents can significantly enhance both accuracy
and conclusiveness, while preserving the collaborative framework between the remaining agents.</p>
      </sec>
      <sec id="sec-4-3">
        <title>4.3. Baselines</title>
        <p>The multi-agent systems within the proposed architectural model for FEVER binary classification
are compared with state-of-the-art approaches, particularly those based on Large Language Models.
These include a perplexity-based method (  ) [23], which uses conditional perplexity scores from
pre-trained language models to classify claim-evidence pairs as either  or   based on
a threshold. Fine-tuned models such as  − ft and   ft [23] are also evaluated for binary
classification. The performances of the multi-agent systems are measured using Accuracy and F1-macro
metrics. Accuracy is calculated as the ratio of correctly predicted instances to the total instances, and
F1-macro is the average of the F1 scores for each class, which is particularly useful for imbalanced
datasets. The F1 score for a class is computed as the harmonic mean of Precision and Recall, with the
F1-macro score being the average of all class F1 scores. If the Decision Agent gives an inconclusive
answer (i.e., one that does not assign a single label), the instance is excluded from the final result. Once
calculated, the results are presented alongside the best baseline scores.</p>
      </sec>
      <sec id="sec-4-4">
        <title>4.4. Results</title>
        <p>Model
 − ft
  ft
  GPT2-XL
Multi-agent system 1
Multi-agent system 2
Multi-agent system 3</p>
        <p>Accuracy (%) F1-Macro (%)</p>
        <p>This section answers the second research question (RQ2): Does a multi-agent system outperform
a single LLM and other baselines on claim verification using this architectural model? . Indeed,
Table 2 presents the performance of diferent models and multi-agent system setups for the claim
verification task, showing the Accuracy and F1-Macro scores. The baseline models include  -ft
and   -ft , with  -ft achieving 52.18% accuracy and 38.82% F1-Macro, while   -ft
performs slightly worse in accuracy (49.18%) but better in F1-Macro (48.42%). The   -GPT2-XL model
outperforms the others with 73.67% accuracy and 71.71% F1-Macro. The multi-agent system setups
show a clear improvement over these baselines, with Multi-agent system 1 achieving 78.01% accuracy
and 77.53% F1-Macro, indicating a notable gain in performance. Multi-agent system 2, without an agent,
achieves even better results with 78.71% accuracy and 78.31% F1-Macro. The best performing setup,
Multi-agent system 3, with fewer problematic agents, significantly outperforms all other models with
85.31% accuracy and 85.29% F1-Macro, demonstrating the efectiveness of the multi-agent architecture
in improving claim verification performance by leveraging specialized agents. These results highlight
the potential of multi-agent systems, particularly in complex tasks like claim verification, where agent
specialization and collaboration contribute to higher accuracy. Lastly, the third research question (RQ3):
What is the relation between the number of agents and performance?, is answered considering
these results and the percentage of inconclusive answers (i.e., answers diferent from a single label)
provided by the Decision Agent in the diverse mutli-agent systems considered.</p>
        <p>Model</p>
        <p>As shown in Table 2, the performance of the multi-agent systems improves as the system complexity
(i.e., number of agents) decreases. Specifically, the most complex setup, Multi-agent system 1, which
involves four agents, achieves 78.01% accuracy and 77.53% F1-Macro. As we reduce the number of
agents in Multi-agent system 2, which has three agents, performance improves slightly. The least
complex system, Multi-agent system 3, with only two agents, achieves the highest performance with
85.31% accuracy and 85.29% F1-Macro, indicating that reducing complexity has a positive impact on
performance. Moreover, when analyzing the percentage of inconclusive answers (i.e., answers diferent
from a single label) provided by the Decision Agent, as shown in Table 3, we observe that the number of
inconclusive answers decreases as the system complexity decreases. The most complex setup, provides
10.65% inconclusive answers, while Multi-agent system 2, with fewer agents, reduces this to 8.89%. The
least complex setup, with only two agents, results in just 1.8% inconclusive answers, showing that
reducing complexity leads to more conclusive results. To conclude - considering the type of agents
employed, their tools and the type of interaction (i.e., the delegation) - there is an inverse relationship
between system complexity in the Reasoning layer and performance, where reducing complexity from
the initial setup to the third setup results in a significant performance improvement, both in terms
of higher accuracy and fewer inconclusive answers. This indicates that in the proposed model, the
specific reasoning tasks and contributions of individual agents led to improved performance when the
number of agents was reduced. However, this outcome may not generalize to all multi-agent systems.
Future research will explore more advanced reasoning models, such as debate-based approaches, to
fully leverage the potential of multi-agent architectures.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Discussion &amp; Limitations</title>
      <p>The results presented in this study highlight the potential of multi-agent systems for the claim
verification task, demonstrating notable improvements in accuracy and F1-macro scores compared to
traditional models. However, certain limitations must be acknowledged. Firstly, the current approach
was tested on a single benchmark dataset (FEVER), and the tasks assigned to some agents, such as
the Public Sentiment Analyst Agent and the Media-Bias Analyst Agent, were not well-suited for this
dataset. This mismatch led to reduced performance in setups that included these agents, suggesting
that the system’s overall efectiveness could be influenced by the nature of the dataset and the specific
responsibilities assigned to agents. Moreover, the evaluation considered only a binary classification
task, and extending the system to multi-class classification or other domains might reveal further
challenges. The performance of the system heavily relies on the interplay between the Reasoning and
Decision layers. In the Reasoning layer, agents are tasked with specific roles, contributing specialized
insights to the claim verification process. However, this specialization also introduces the risk of
misalignment between the tasks of individual agents and the dataset requirements, as observed in the
less efective setups. The Decision layer, while pivotal in synthesizing outputs from the Reasoning layer,
faces challenges when agent outputs are ambiguous or contradictory. The percentage of inconclusive
answers provided by the Decision Agent, as shown in the experiments, underscores the importance of
refining the mechanisms through which this layer resolves uncertainties and ensures consistency. Also,
while reducing the system’s complexity improved its performance, it remains unclear whether adding
more specialized agents with better cooperation could enhance outcomes. The reduced complexity in
Multi-agent system 3 highlighted the importance of eficient collaboration among agents within the
Reasoning layer and the need for the Decision layer to adapt dynamically to varying levels of input
complexity. For future work, several directions could be pursued. Testing a more collaborative approach
between agents in the Reasoning layer, possibly through improved communication protocols or shared
memory mechanisms, could lead to better coordination and enhanced results. Enhancing the Decision
layer with more sophisticated aggregation and uncertainty resolution techniques could further improve
the system’s robustness, or increasing the parameter  of Decision Agents. Expanding the evaluation
to other datasets and tasks would also provide a more comprehensive understanding of the system’s
versatility. Additionally, integrating advanced methods for dynamic agent task allocation could enable
the system to adapt to diferent datasets and objectives, further improving its scalability and robustness.
Despite these limitations, the proposed multi-agent system architectural model demonstrates significant
promise, providing a solid foundation for future advancements in automated claim verification.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusions</title>
      <p>This work presents a novel multi-agent architectural model for claim verification, leveraging Large
Language Models (LLMs) within a modular and adaptable framework. Specialized agents in the
Reasoning layer, supported by ReAct and Reflexion mechanisms, collaborate to provide insights synthesized
by a Decision layer into a final verdict. The proposed multi-agent architectural model outperformed
traditional baselines, with Multi-agent system 3 achieving 85.31% accuracy and 85.29% F1-Macro,
significantly surpassing the best-performing baseline. These findings establish the potential of multi-agent
systems to enhance claim verification and fact-checking processes.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgments</title>
      <p>This work was partially supported by project SERICS (PE00000014) under the MUR National Recovery
and Resilience Plan funded by the European Union - NextGenerationEU.</p>
    </sec>
    <sec id="sec-8">
      <title>Declaration of Generative AI</title>
      <sec id="sec-8-1">
        <title>The authors have not employed any Generative AI tools.</title>
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