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Evaluating conversational AI systems that use external tools is challenging, as errors can arise from complex interactions among user, agent, and tools. While existing evaluation methods assess either user satisfaction or agents&#39; tool-calling capabilities, they fail to capture critical errors in multi-turn tool-augmented dialogues—such as when agents misinterpret tool results yet appear satisfactory to users. We introduce TRACE, a benchmark of systematically synthesized tool-augmented conversations covering diverse error cases. Evaluation with state-of-the-art conversation evaluation frameworks reveals that all approaches remain far from ideal performance, demonstrating the fundamental difficulty of this benchmark.

ACL 2026

Multi-Faceted Evaluation of Tool-Augmented Dialogue Systems

llm agent evaluation

data synthesis

conversational ai

## Welcome to NAACL 2022!
The Annual Meeting of the North American Chapter of the Association for Computational Linguistics (NAACL) is taking place July 10-15, 2022 as a hybrid event, in Seattle, WA and online. We are happy to welcome all of you to conference! 
 
The main conference program features oral presentations, in-person and virtual posters and demo sessions, a plenary session for our best paper presentations and awards, keynote presentations, a plenary panel on the place of linguistics and symbolic structures in NLP, and an Industrial Track panel on Careers in NLP.
 
Posters (including Findings of NAACL 2022) and demos are grouped by areas for both the in-person and the virtual sessions. For the virtual component, the talks will be on Zoom and the posters and the demos will be in GatherTown. The Student Research Workshop and will have an oral session and a poster session.
 
The program also features 6 Tutorials and 26 Workshops.
 
 We wish you a wonderful conference!
 
[The NAACL 2022 Organizing Committee](https://2022.naacl.org/committees/organization/)

NAACL 2022

2022 Annual Conference of the North American Chapter of the Association for Computational Linguistics

Evaluating conversational AI systems that use external tools is challenging, as errors can arise from complex interactions among user, agent, and tools. While existing evaluation methods assess either user satisfaction or agents' tool-calling capabilities, they fail to capture critical errors in multi-turn tool-augmented dialogues—such as when agents misinterpret tool results yet appear satisfactory to users. We introduce TRACE, a benchmark of systematically synthesized tool-augmented conversations covering diverse error cases. Evaluation with state-of-the-art conversation evaluation frameworks reveals that all approaches remain far from ideal performance, demonstrating the fundamental difficulty of this benchmark.

workshop paper

It is my great pleasure and honor to welcome you to the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026), held in San Diego, California, USA, July 2–7, 2026. ACL 2026 continues our fields tradition of excellence in scholarship, innovation, and inclusivity, and I am deeply grateful to the many volunteers who have worked tirelessly to bring this event to life.

It is exciting to see the many developments in the field reflected at our conference, such as the advancement of large language models (born out of our community) into many application directions. This is not without challenges, partly due to unsolved problems, and partly due to misuse of the technology. All this is reflected well at ACL 2026. The conference also reflects that the field is not only about advancing technology, but also the science of fundamentally understanding language and how it is use by many different speaker communities. 
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The 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026) will take place in San Diego, California, from July 2 - 7, 2026.

We present a domain-grounded benchmark and evaluation framework for tool-aware plan generation in contact-center analytics, where answering a business-insights query requires decomposing it into executable steps over structured tools (Text2SQL over Snowflake), unstructured tools (RAG over transcripts), and LLM-based synthesis, with explicit depends_on relations for safe parallel execution. Our contributions are threefold: (i) a reference-based plan evaluation framework with two complementary views—a metric-wise evaluator spanning seven dimensions (e.g., tool–prompt alignment, query adherence) and a one-shot evaluator that compares a candidate plan against a reference plan; (ii) a lineage-driven data curation methodology that uses an iterative evaluator→optimizer loop to refine initial plans into high-quality plan lineages while reducing manual effort; and (iii) a large-scale study of 14 LLMs across model families and sizes on their ability to generate step-by-step, executable, tool-assigned plans, evaluated with and without lineage in the prompt. Empirically, LLMs continue to struggle on compound queries and on plans longer than four steps; the highest aggregate metric-wise score is 84.8 (Claude-3-7-Sonnet), while the strongest one-shot A+ rate (Extremely Good or Very Good) is only 49.75% (o3-mini). Lineage yields mixed overall gains but improves several strong models and often helps step executability. Overall, our results expose persistent weaknesses in tool understanding—especially tool–prompt alignment and tool-usage completeness—and show that shorter, simpler plans remain markedly easier. The benchmark, evaluation framework, and findings provide a practical path for assessing and improving agentic planning with tools in enterprise question-answering settings. An anonymized dataset with human-annotated reference plans, plan lineages, and per-planner outputs for all 14 planners is available at the anonymous repository linked in the paper.

Tool-Aware Planning in Contact Center AI: Evaluating LLMs through Lineage-Guided Query Decomposition

Time series data are integral to applications across domains such as finance, healthcare, transportation, and environmental science. While recent work has begun to explore time series question answering (QA), existing benchmarks still provide limited coverage of analytical capabilities under a standardized evaluation framework. We introduce TSAQA, a novel unified benchmark designed to broaden task coverage and evaluate diverse temporal analysis capabilities. TSAQA integrates 6 diverse tasks under a single framework ranging from conventional analysis, including anomaly detection and classification, to advanced analysis, such as characterization, comparison, data transformation, and temporal relationship analysis. Spanning 210k samples across 13 domains, the dataset employs diverse formats, including true-or-false (TF), multiple-choice (MC), and a novel puzzling (PZ), to comprehensively assess time series analysis. Zero-shot evaluation shows that TSAQA remains challenging for current Large Language Models (LLMs): best-performing commercial model, Gemini-2.5-Flash, achieves 65.08 average accuracy. Although instruction tuning improves open-source models’ performance: the best- performing model, LLaMA-3.1-8B, shows significant room for improvement. We further evaluate language-capable time series foundation models (TSFMs), showing that TSAQA extends beyond general-purpose LLMs. The data are available in https://huggingface.co/datasets/TSAQA/TSAQA-Benchmark.

TSAQA: Time Series Analysis Question And Answering Benchmark

Prior research demonstrates that the performance of language models on reasoning tasks can be influenced by suggestions, hints, and endorsements. However, the influence of endorsement source credibility remains underexplored. We investigate whether language models exhibit systematic bias based on the perceived expertise of the provider of the endorsement. Across 4 datasets spanning mathematical, legal, and medical reasoning, we evaluate 11 models using personas representing four expertise levels per domain. Our results reveal that models are increasingly susceptible to incorrect or misleading endorsements as source expertise increases, with higher-authority sources inducing not only accuracy degradation but also increased confidence in wrong answers. We also show that this authority bias is mechanistically encoded within the model and a model can be steered away from the bias, thereby improving its performance even when an expert gives a misleading endorsement.

Who Endorsed It? Measuring Authority Bias Across Expertise Levels in Language Models

In human conversation, both interlocutors play an active role in maintaining mutual understanding. When listeners are uncertain about what speakers mean, for example, they can request clarification. It is an open question for language models whether they can assume a similar listener role, recognizing and expressing their own uncertainty through clarification. We argue that reference games are a suitable testbed to approach this question as they are controlled, self-contained, and make clarification needs explicit and measurable. To test this, we evaluate three vision-language models comparing a baseline reference resolution task to an experiment where the models are instructed to request clarification when uncertain. The results suggest that even in such simple tasks, models often struggle to recognize internal uncertainty and translate it into adequate clarification behavior. This demonstrates the value of reference games as testbeds for interaction qualities of (vision and) language models.

Reference Games as a Testbed for the Alignment of Model Uncertainty and Clarification Requests

Systematic reviews are a cornerstone of modern science, synthesising evidence from published research to provide the highest level of research evidence in a field. The process includes categorising studies on a number of different dimensions which is laborious and time consuming. Automatic approaches are beginning to be explored but the complexity of the task means we are currently far from a satisfactory solution. In this paper, we test different annotation scheme-agnostic methods for automatic NLP paper categorisation for systematic reviews, and test them on two tasks: (i) annotating NLP papers for categories of reported controlled-text generation methods, and (ii) annotating NLP papers for categories of reported human evaluations. We find that reasoning-enhanced fine-tuning combined with DAPO reinforcement learning rewarding both correctness and output format substantially improves the performance of LLMs (by up to +53.8 points), even when they have been pre-trained to perform reasoning, and cuts time required for annotation by around 80\% in a human-in-the-loop setting.

Automatic Paper Analysis and Categorisation for Systematic Reviews with Combined Reasoning-Augmented SFT and DAPO RL

Generating coherent, semantically accurate text from large structured inputs remains a persistent challenge in data-to-text generation, as single-step LLM mappings from data-to-text limit control over discourse structuring and amplify hallucinations and omissions as input size grows. We introduce a new dataset of extended DBpedia triple sets (up to 199 triples per input), and a modular multi-agent framework: specialised LLM agents handle content ordering, text structuring, and surface realisation under the supervision of an orchestrator and guardrail control loop. The system generates multi-paragraph outputs in English and Irish (low-resource). We compare a three-worker multi-agent configuration against a single-worker multi-task variant and a strong end-to-end baseline. Quality is assessed via human evaluation and LLM-as-a-judge (with truncation-based sanity checks). Results show slightly superior coherence for the multi-agent approach in both languages, with statistically significant inter-rater correlation over all criteria for English and no statistically significant correlation for Irish. Human-LLM alignment is very weak overall, thus exposing key limits in scalable NLG evaluation.

LLM Multi-Agent Systems for Long Triple Set Data-to-Text Generation

While Large Language Models (LLMs) can generate fluent and convincing responses, they are not necessarily correct. This is especially apparent in the popular decompose-then-verify factuality evaluation pipeline, where LLMs evaluate generated text by decomposing it into individual, valid claims. Factuality evaluation is especially important for medical answers, since incorrect medical information could seriously harm the patient. However, existing factuality systems are a poor match for the medical domain, as they are typically only evaluated on objective, entity-centric, formulaic texts such as biographies and historical topics. This differs from condition-dependent, conversational, hypothetical, sentence-structure diverse, and subjective medical answers, making decomposition into valid facts challenging. We propose MedScore, a new pipeline to decompose medical answers into condition-aware valid facts and verify against in-domain corpora. Our method extracts up to three times as many valid facts as existing methods, reducing hallucination and vague references, and retaining condition-dependency in facts. We also find MedScore is generalizable to non-medical domains without any specific tuning. The resulting factuality score substantially varies by decomposition method, verification corpus, and used backbone LLM, highlighting the importance of customizing each step for reliable factuality evaluation by using our generalizable and modularized pipeline for domain adaptation.

MedScore: Generalizable Factuality Evaluation of Open-ended Long-form Medical Answers by Domain-adapted Claim Decomposition and Verification

Reproducibility of human evaluations in Natural Language Processing remains a critical open challenge. This paper presents a third independent replication of the human evaluation from Yao et al. (2022), which assessed an automated Question-Answer Generation (QAG) system for children's storybooks against a baseline system and human-authored ground truth, across three criteria --- Readability, Question Relevance, and Answer Relevance --- using five NLP-literate annotators. Our replication confirms the main findings of the original study: the QAG system outperforms the baseline on Readability and Question Relevance, and Ground Truth ranks highest across all criteria. System rankings are preserved across all three criteria, with the exception of a statistically non-significant difference in Answer Relevance. This holds true despite a severe drop in inter-annotator agreement for Readability. We further document several methodological concerns, some unreported in prior replications, including data quality issues and evaluation design limitations identified during our pilot study.

ReproNLP 2026: A Third Replication of the Human Evaluation of a QAG System for Children’s Storybooks

Evaluating long-form answers from retrieval-augmented generation (RAG) systems remains challenging: human evaluation is expensive, while automatic metrics must reliably capture answer completeness. The AutoNuggetizer framework addresses this by decomposing evaluation into atomic facts (nuggets) and using LLMs for both nugget creation and assignment. The original study validated this approach on open-ended TREC RAG queries; however, it remains unclear whether the same cost-quality tradeoffs hold for structurally different tasks. We reproduce AutoNuggetizer on seven RAG systems over the QAMPARI list-QA benchmark, where answers consist of discrete entities and omissions are more directly measurable. Our results directionally reproduce the original findings: fully automatic evaluation preserves run-level rankings, assignment-only automation yields stronger agreement than end-to-end automation, and LLM-based assignment is highly concordant with human labels while being modestly stricter. These findings support the use of AutoNuggetizer for comparative evaluation beyond open-ended RAG, while also identifying systematic biases in automatic nugget creation and assignment.

Do Nugget-Based Evaluation Patterns Generalize to List-QA?

Recent work in NLP has probed large language models for their understanding of cultural norms across countries. However, this work typically considers distributional patterns, ignoring group consensus or possible multicultural environments within a country. In this work, we leverage cultural consensus theory (CCT) from cultural anthropology to model such multidimensional nuance. Applying CCT to the World Values Survey (WVS) across 10 countries and 12 domains, we demonstrate that models frequently misrepresent cultural structures by either failing to form cohesive consensus or severely over-regularizing consensus. Through explicit representation of intra-group variance, CCT provides actionable diagnostics to evaluate when models reflect true human diversity versus algorithmic homogenization.

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