NeurIPS 2026 Papers

Conference on Neural Information Processing Systems

Decision breakdown

6,437papers

Counted from the official paper list; may differ slightly from the number the conference announced.

  • Oral
    991.5%
  • Spotlight
    2403.7%
  • Poster
    6,09894.7%

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Topic: Datasets and Benchmarks · 623 papers · Reset filters

RSSA: Robust Semantic and Spatial Aligner for Collaborative Perception

Zhihao Yang, Zhiyu Xiang, Peng Xu, Tianyu Pu, Kai Wang, Eryun Liu, Dongping Zhang, Yong Ding

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V2X collaborative perception improves single-vehicle perception by aggregating multi-view features from collaborative agents. However, existing methods typically rely on simple spatial warping to align the collaborative features, which can cause semantic misalignment during fusion. Meanwhile, these deterministic warping-based methods are highly sensitive to the positional noises. In this paper, we propose a plug-in module called Robust Semantic and Spatial Aligner (RSSA), which performs semantic and probabilistic spatial transformations for robust feature alignment. Specifically, a Semantic Transformation (SemT) block modulates feature channels based on the observed relative pose to correct semantic inconsistencies. Subsequently, a Probabilistic Spatial Transformation (P-SpaT) block performs probabilistic warping by sampling from the Gaussian-modeled relative pose space. A Relative Transformation Augmentation (RT-Aug) strategy is further introduced to augment the relative poses and facilitate the training of the RSSA. Extensive experiments on both simulated and real-world datasets demonstrate that RSSA improves the state-of-the-art methods by a large margin under the configuration of both clean and noisy positions.

Poster
RESCAST-100K: A Comprehensive Dataset for Cross-Domain Residential Load and Indoor Temperature Forecasting

Jainam Dhruva, Yousaf Raza, A. B. Siddique, Simone Silvestri

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Accurate short-term forecasting of residential energy load and indoor temperature is essential for home energy management systems, grid-level demand response participation, and community-level energy efficiency programs. Domain adaptation methods and transfer learning have shown promise in improving forecasting accuracy under data heterogeneity and scarcity scenarios commonly observed at the residential level. However, progress remains limited by the absence of comprehensive residential datasets: existing ones are narrow in target coverage and lack structured support for cross-domain evaluation. To address this, we introduce RESCAST-100K, a large-scale residential forecasting benchmark for studying cross-domain generalization. It exposes a configuration-driven interface that instantiates source and target domains along interpretable axes, such as geography, climate zone, wall construction, and heating equipment, supporting systematic evaluation of transfer learning, domain adaptation, and zero-shot generalization under controlled domain shifts. The benchmark covers approximately 100,000 EnergyPlus-simulated U.S. homes derived from ResStock, providing 15-minute time series of three coupled targets per home, namely total load, HVAC (heating, ventilation, and air conditioning) load, and indoor temperature, together with weather channels, HVAC setpoints, and over 40 static building covariates. Finally, it integrates five real-world residential datasets under a unified schema, supporting sim-to-real evaluation on the same tasks. We benchmark models from recurrent, attention, and MLP-mixer architectures for zero-shot performance across different domains, under missing input data conditions, for each task. Cross-attention and MLP-mixer based models consistently outperform recurrent and classical transformer-based baselines under domain shift. RESCAST-100K is intended to support the machine learning and building analytics communities in advancing cross-domain residential forecasting at the home, community, and grid levels.

Poster
RAOP: Step-Level Resource Orchestration for LLM Agents across Edge and Cloud

Jinze Li, Xin Yang, Shuo Yang, Jinfeng Xu, Edith C Ngai

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LLM agents do not present a fixed inference job to an edge and cloud system. At each step, a placement decision chooses where to generate the next message, where to execute any resulting tool call, which prefix must be replayed, which cache state is updated, and whether the episode continues. As a result, the workload to be scheduled is partly produced by the scheduling decisions themselves. We formalize this problem as an *endogenous, sequentially revealed workload* (ESRW) controlled trajectory MDP. We then introduce **Resource Aware Orchestration Policy** (RAOP), a step level orchestration policy that first places language generation and then, after observing any tool call, places tool execution. RAOP predicts candidate action workloads from prefix replay, prefill, KV cache residency, queue, network, and tool payload features, and is trained with GRPO to optimize measured full trajectory success and latency rather than a one step latency surrogate. To make controlled evaluation auditable, the main simulator replays language and tool continuations produced by real model and tool execution while recomputing physical timing under the sampled placement sequence. As an analytical lens, we derive a Bellman regret decomposition showing that myopic placement policies incur error from workload prediction, success priors, and a controlled endogeneity term. On GSM8K, HotpotQA, WebShop, and a calibrated three tier deployment, RAOP matches the strong cloud only success reference while reducing P99 latency by about 53\% and communication by about 73\%. Against the strongest learned step level baseline, RAOP improves average success by 2.5 points, indicating that full trajectory optimization is central for agent orchestration.

Spotlight
RAM-H1200: A Unified Evaluation and Dataset on Hand Radiographs for Rheumatoid Arthritis

SONGXIAO YANG, Haolin Wang, Yao Fu, Junmu Peng, Lin Fan, Hongruixuan Chen, Jian Song, Masayuki Ikebe, Shinya Takamaeda-Yamazaki, Masatoshi Okutomi, Tamostu Kamishima, Yafei Ou

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Rheumatoid arthritis (RA) assessment from hand radiographs requires multi-level analysis and modeling of anatomical structures and fine-grained local pathological changes. However, existing public resources do not support such multi-level analysis, often lacking full-hand coverage, fine-grained annotations, and consistent integration with clinical scoring systems. In particular, annotations that enable quantitative analysis of bone erosion (BE) remain scarce. RAM-H1200 contains 1,200 hand radiographs from a regional, multi-institutional Japanese cohort collected across six medical centers in the Sapporo region, with multi-level annotations including (i) whole-hand bone structure instance segmentation, (ii) pixel-level BE masks, (iii) Sharp/van der Heijde (SvdH)-defined joint regions of interest, and (iv) joint-level SvdH scores for both BE and joint space narrowing (JSN). It provides a common evaluation resource covering anatomical structure modeling, localized erosive pathology analysis, and clinically standardized RA severity assessment from the same radiographs. The proposed BE masks enable, for the first time, quantitative BE analysis beyond coarse categorical grading by providing explicit spatial supervision for lesion extent and morphology. To our knowledge, RAM-H1200 is the first public benchmark resource providing whole-hand bone structure instance segmentation, pixel-level BE delineation, and clinically grounded joint-level SvdH scoring for both BE and JSN. Results across benchmark tasks show that anatomical modeling is substantially more mature than quantitative BE analysis: whole-hand bone segmentation achieves strong performance, whereas BE segmentation remains a major open challenge. By providing multi-level annotations spanning anatomical structure modeling, quantitative lesion analysis, and clinically grounded SvdH scoring, RAM-H1200 provides a comprehensive benchmark resource for RA analysis on hand radiographs. Benchmark \& Code: https://github.com/YSongxiao/RAM-H1200 Dataset Repository: https://huggingface.co/datasets/TokyoTechMagicYang/RAM-H1200-v1

Poster
RADAR: Relative Angular Divergence Across Representations

Xavier Cadet, Mateusz Nowak, Peter Chin

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Machine learning methods rely on data. However, gathering suitable data can be challenging due to availability constraints, cost, or the need for domain expertise. Expanding datasets with additional sources is a common response to limited data, yet this practice does not always improve downstream performance and can sometimes lead to a loss of performance, known as negative transfer. We propose RADAR, a simple, geometrically grounded metric for estimating cross-domain transferability in foundation models. RADAR analyzes the layer-wise evolution of representations by measuring angular alignments and relative changes in distance along layer-to-layer displacement trajectories, and by comparing empirical distributions of within-domain and cross-domain dynamics. We hypothesize that domain transferability is related to the divergence between these trajectory distributions. We evaluate the metric across multiple modalities, including cross-lingual sentiment classification with text embedding models and cross-domain image classification with foundation vision models. Across several settings, RADAR provides competitive predictive performance relative to existing transferability metrics on several vision and text benchmarks, with particularly strong results when domain transitions are smooth or cleanly separated. Our ablations further suggest that the effectiveness of transferability estimation depends on the geometry of the model’s internal representation space, with different modalities favoring different topological formulations.

Poster
RAD-TFM: Robust and Domain-Adapted Tabular Foundation Models

Matthew Peroni, Franck Le, Vadim Sheinin

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The development of tabular foundation models (TFMs) has accelerated in recent years, showing strong potential to outperform traditional ML methods for structured data. A key finding is that TFMs can be pretrained entirely on synthetic datasets, opening opportunities to design data generators that encourage desirable model properties. Prior work has mainly focused on crafting high-quality priors over generators to improve overall pretraining performance. Our insight is that parameterizing the generator distribution enables an adversarial, distributional robustness perspective: during training, we can adapt the generator to emphasize datasets that are particularly challenging for the model, which we formalize by introducing an optimality gap measure. Further, we develop a method to align the synthetic data generation with real-world datasets from a given domain, constraining the adversary to generate "realistic'" data. Together, these algorithms comprise the Robust and Domain-Adapted Tabular Foundation Models (RAD-TFM) pipeline, a model-agnostic adversarial training framework. Applied to the TabPFN V2 classifier, RAD-TFM improves performance across 6 diverse tabular benchmarks, with up to a 11\% increase in mean normalized AUC over the original TabPFN and other baseline algorithms, with only 100k additional training datasets, less than 0.1\% of the original pretraining data. These results highlight a promising new direction for targeted adversarial training and fine-tuning of TFMs using synthetic data alone.

Poster
QDMouse4M: A Multi-View 3D Mouse Spontaneous Behavior Dataset with Quantum-Dot Markers

Jingyang Ke, Amartya Pradhan, XUELING ZHANG, Weihan Li, Anqi Wu, Jeffrey Markowitz

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Quantitative analysis of animal behavior in neuroscience increasingly relies on accurate 3D pose, yet current large-scale mouse datasets are restricted to top-down views and suffer from occlusion and keypoint ambiguity. We introduce QDMouse4M, a six-view dataset of freely moving mice with physically grounded 2D and 3D keypoint annotations obtained from subdermal quantum-dot fluorescence markers. QDMouse4M contains over four million reflectance frames with matched fluorescence frames, 2D and 3D pose trajectories and behavior classifications. We use the dataset to evaluate markerless 2D and 3D pose estimation with SLEAP and Lightning Pose 3D across training-set sizes, backbones, and in-session/out-of-session splits. We further show that the released trajectories support downstream spontaneous-behavior analysis with Keypoint-MoSeq and stride-level gait measurements. QDMouse4M provides a benchmark-scale, physically grounded resource for developing and evaluating pose estimation, behavior understanding, and biomechanics models under realistic dark-environment laboratory conditions.

Poster
Q-MMR: Off-Policy Evaluation via Recursive Reweighting and Moment Matching

Nan Jiang, Xiang Li

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We present a novel theoretical framework, Q-MMR, for off-policy evaluation in finite-horizon MDPs. Q-MMR learns a set of scalar weights, one for each data point, such that the reweighted rewards approximates the expected return under the target policy. The weights are learned inductively in a top-down manner via a moment matching objective against a value-function discriminator class. Notably, and perhaps surprisingly, a data-dependent finite-sample guarantee for general function approximation can be established under only the realizability of $Q^\pi$, with a **dimension-free** bound---that is, the error does **not** depend on the statistical complexity of the function class. We also establish connections to several existing methods, such as linear FQE. Further theoretical analyses shed new light on the nature of coverage, a concept of fundamental importance to offline RL.

Poster
Prudent-Banker: No Extra Fees for Baseline Safety in Adversarial Bandits With and Without Delays

Ting Hu, Luanda Cai, Emmanouil-Vasileios Vlatakis-Gkaragkounis

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We study adversarial multi-armed bandits with and without delayed feedback under a **safety-aware** goal: achieving minimax-optimal worst-case regret while keeping nearly **constant** regret relative to a designated "safe" baseline policy. Existing approaches can balance this trade-off with immediate feedback for smooth comparators, but arbitrary delays can mistime transitions between **conservatism** and **exploration**, endangering the safety guarantee. To bridge this gap, we propose PRUDENT-BANKER, a novel algorithm that combines a delay-adapted variant of Online Mirror Descent with a modified phased-aggression mechanism. Its key technical contribution is a delay-calibrated restart threshold that rigorously accounts for the worst-case distortion induced by unobserved feedback and reliably detects comparator suboptimality. We also establish new lower bounds for safety-constrained adversarial delayed bandits, showing that the regret guarantees of PRUDENT-BANKER are unimprovable, up to logarithmic factors, under the baseline-safety requirement. To the best of our knowledge, PRUDENT-BANKER is the first algorithm to achieve the optimal safety–robustness trade-off: pseudo-regret $\tilde{O}(\sqrt{T}+\sqrt{D})$ together with $\tilde{O}(1)$ regret against the safe comparator, both with and without delays. Experiments across diverse delay distributions show that, unlike standard delay-robust baselines, PRUDENT-BANKER effectively balances safety and learning.

Poster
ProtGlycanDock: Towards Accurate Protein-Glycan Docking with Tailored Dataset, Benchmark and Model

Minghao Xu, Jiaze Song, Jinyu Wang, Wentao Zhang

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Performing accurate protein-glycan docking is critical to understanding protein-glycan interactions which govern many biological processes. However, this important task is hampered by the lack of tailored datasets, benchmarks and models for protein-glycan docking. To fill this blank, we first curate a standard benchmark **ProtGlycanDock** for training and evaluating protein-glycan docking models under both protein and glycan generalization settings. On this benchmark, we evaluate ten models in three categories, physics-based docking methods, machine-learning-based docking models and molecular structure prediction models. To obtain more precise binding poses, we further propose two finetuning techniques to inject the knowledge of glycan conformations into a general-purpose molecular structure prediction model. These two techniques respectively augment model inputs with glycan topological features and refine glycan binding pose with a glycan energy loss. Benchmark results show the superiority of AlphaFold~3 among existing methods, and the two proposed finetuning techniques can be well combined to achieve a state-of-the-art model for protein-glycan docking. Also, we perform stratified benchmark analysis and case studies to better understand the strengths and weaknesses of current models, providing insights for future model improvements. We maintain datasets at https://huggingface.co/datasets/ProtGlycanDock/ProtGlycanDock and source codes at https://github.com/kasawa1234/ProtGlycanDock.

Poster
Projection Learning: A Principled Way to Overcome Memorization in Distribution Learning

Lin Chen, Dejan Slepcev

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We introduce a framework for learning distributions supported on manifolds based on estimating the projection onto the underlying data manifold. Specifically, we define an objective functional over a class of functions whose minimizer recovers this projection. The proposed framework automatically adapts to the intrinsic dimension and allows for data supported on unions of manifolds with varying dimensions. The resulting objective can be optimized using standard neural network architectures. We present population-level results establishing recovery of the manifold projection and prove finite-sample Wasserstein generalization bounds. Furthermore, we validate the approach empirically across a range of settings. In contrast to widely used generative models such as diffusion models, whose objectives can be minimized by memorizing training samples, our formulation penalizes such behavior. Thus, returning training data does not yield low loss. We also introduce a direct memorization metric to verify that the learned projection generates new samples rather than reproducing the training set.

Poster
Progressive Signal Calibration for Medical Image Segmentation: Diagnosing and Correcting Structural Misalignment in Training Signals

Xinyan Zhao, Haijing Liu, Zhuan Cui, Tian Guan, Yonghong He, Wen Tang, Qiming He

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Training-signal imbalance in medical image segmentation is commonly diagnosed as a data-distribution problem, such as class frequency imbalance, foreground sparsity, or domain shift, and addressed through reweighting, sampling, or domain adaptation. We argue that this diagnosis is incomplete: a more fundamental source is structural misalignment between supervision targets and segmentation objectives. Weidentify two operative mechanisms underlying this phenomenon: gradient-mass dilution, where dominant classes consume gradient capacity needed for foreground discrimination, and inter-class supervision noise, where weak subtype boundaries generate unreliable optimization signals. On a private renal pathology dataset, four standard segmentation architectures trained under conventional four-class supervision underperform a foreground-focused supervision regime (a one-line modification of the loss) by 7.87–16.05 fg-mIoU points. The same effect replicates on three public datasets, suggesting foreground-focused supervision as a low-cost, general-purpose recipe for any pixel-imbalanced segmentation task. Building on this observation, we propose Progressive Signal Calibration (PSC), a framework that calibrates training signals at three abstraction levels. At the annotation level, PSC adaptively selects the supervision granularity that maximizes signal qual ity. At the architectural level, PSC introduces a boundary-aware feature gating mechanism for structure-sensitive feature aggregation. At the regularization level, PSC employs uncertainty- and ratio-aware constraints to stabilize optimization and prevent late-stage class-proportion drift. Importantly, PSC satisfies a con ditional gain monotonicity property: when structural misalignment is weak or absent, its regularization terms naturally attenuate, avoiding systematic degradation. Across 18 public histopathology benchmarks, PSC achieves statistically significant improvement on six datasets with no statistically significant regression on any benchmark. On the private renal pathology dataset, PSC reaches 96.0 fg-mIoU, ex ceeding the strongest matched-backbone baseline by +2.56 points under identical FG3 supervision—a substantial gain in a regime where the FG3 baseline is already above 93 fg-mIoU

Poster
ProgramBench: Can Language Models Rebuild Programs From Scratch?

John Yang, Kilian Lieret, Jeffrey Ma, Parth Thakkar, Dmitrii Pedchenko, Sten Sootla, Emily McMilin, Pengcheng Yin, Rui Hou, Gabriel Synnaeve, Diyi Yang, Ofir Press

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Turning ideas into full software projects from scratch has become a popular use case for language models. Agents are being deployed to seed, maintain, and grow codebases over extended periods with minimal human oversight. Such settings require models to make high-level software architecture decisions. However, existing benchmarks measure focused, limited tasks such as fixing a single bug or developing a single, specified feature. We therefore introduce ProgramBench to measure the ability of software engineering agents to develop software holisitically. In ProgramBench, given only a program and its documentation, agents must architect and implement a codebase that matches the reference executable’s behavior. End-to-end behavioral tests are generated via agent-driven fuzzing, enabling evaluation without prescribing implementation structure. Our 200 tasks range from compact CLI tools to widely used software such as FFmpeg, SQLite, and the PHP interpreter. We evaluate 9 LMs and find that none fully resolve any task, with the best model passing 95% of tests on only 3% of tasks. Models favor monolithic, single-file implementations that diverge sharply from human-written code.

Poster
Process-conditioned Pretraining with Topographic Spatial Retrieval for Large EEG Models

Yi Ding, Muyun Jiang, Weibang Jiang, Shuailei Zhang, XINLIANG ZHOU, Chenyu Liu, Shanglin Li, Yong Li, Cuntai Guan

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Large EEG foundation models are pretrained on heterogeneous corpora, but two challenges remain underexplored: (1) experimental protocols provide mental-process cues that are rarely used in masked pretraining, and (2) electrode montages vary across datasets, making spatial representations montage-dependent. Existing methods typically learn a single general-purpose representation and model spatial structure implicitly, limiting their ability to exploit process-related information under montage heterogeneity. We introduce BrainPro, a process-conditioned self-supervised pretraining framework that couples topographic spatial retrieval with shared and process-associated representation learning. BrainPro maps dataset-specific montages to a universal channel-region template and retrieves channel- and region-level spatial filters to form a topographically aligned spatial basis. Over this basis, BrainPro learns a shared encoder for general EEG structure and additional affective, motor-related, and auxiliary residual branches for process-associated variation. Protocol-derived mental-process cues condition branch activation and region-weighted masked reconstruction, incorporating topographic spatial priors and process information without using downstream class labels. Across nine public BCI benchmarks, BrainPro achieves strong performance among evaluated baselines. Ablations, channel-drop analysis, encoder-configuration studies, and spatial-filter visualizations suggest that topographic spatial retrieval and process-conditioned representation learning jointly improve EEG decoding.

Poster
Probabilistic Tiny Recursive Model

Amin Sghaier, Ali Parviz, Alexia Jolicoeur-Martineau

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Tiny Recursive Models (TRM) solve complex reasoning tasks with a fraction of the parameters of modern large language models (LLMs) by iteratively refining a latent state and final answer. While powerful, their deterministic recursion can lead to convergence at suboptimal solutions, without escape mechanism. A common workaround relies on task-specific input perturbations at test time combined with answer aggregation via voting. We introduce Probabilistic TRM (PTRM), a task-agnostic framework for test-time compute scaling that addresses this limitation through stochastic exploration. PTRM injects Gaussian noise at each deep recursion step, enabling parallel trajectories to explore diverse solution basins, and selects among them using the model’s existing Q head (used for early stopping in the original TRM). Without requiring retraining or task-specific augmentations, PTRM enables substantial accuracy gains across benchmarks, including Sudoku-Extreme (87.4% to 98.75%) and on various puzzles from Pencil Puzzle Bench (65% to 91%). On the latter, PTRM achieves nearly double the accuracy of frontier LLMs (91% vs. 55%) at less than 0.0001x the cost, using only 7M parameters.

Poster
ProactBench: Beyond What The User Asked For

Sepehr Harfi Moridani, Ahmad Salimi, Dongming Shen, Alexander Smola

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Most LLM benchmarks score how well a model responds to explicit requests. They leave unmeasured a different conversational ability: noticing and acting on needs the user has implied but not said. We call this conversational proactivity. ProactBench decomposes it into three phase-tied types: Emergent, inference from a single disclosed anchor; Critical, synthesis across multiple anchors; and Recovery, grounded forward-looking value after task completion. We operationalise the benchmark with three agents: a Planner, a User Agent, and an Assistant Model. Their information asymmetries defend against style-confounded scoring, rubric leakage, external-context contamination, and information dumps. The released corpus contains 198 curated dialogues with 624 trigger points across 24 communication styles drawn from a psychometric inventory and audited by an independent LLM judge. Across 16 frontier and open-weight models, Recovery is both difficult and weakly predicted by six standard benchmarks, making it a useful new evaluation signal.

Poster
ProCARE: Real-World Study Automation via Profile-Grounded Evidence Contracts

Zhaoyu Fan, Bowen Han, Yanwei Ren, Jincheng Ou, Siyi Cao, Zehua He, Kaiyu Huang, Pengcheng He, Shanshan Ni, Chengchen Gong, Qingjiang Shi

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Real-world studies (RWS) analyze routinely collected healthcare data, such as electronic health records and insurance claims, to estimate treatment effects, monitor safety, and identify risk factors outside randomized trials. Automating RWS with large language model agents is appealing but brittle: valid analyses depend on dataset-specific clinical semantics, including index dates, follow-up windows, patient/event-level units, and outcome boundaries that are often implicit in observational data. This leads to schema mismatches, temporal errors, inconsistent analytical granularity, and unsupported clinical claims. We present ProCARE, a profile-grounded framework that reformulates RWS automation as constrained compilation. ProCARE converts heterogeneous data profiles into Evidence Contracts specifying available variables, temporal attributes, distributions, and evidentiary limits, and compiles study objectives into RWS-IR, a strongly typed intermediate representation for variables, time relations, analysis units, and statistical tasks. Deterministic validation and localized repair then check and revise generated workflows across schema mapping, cohort construction, variable derivation, analysis, and interpretation. On 36 EHR-based benchmark tasks, ProCARE outperforms strong LLM-agent baselines in code executability, semantic consistency, and conclusion traceability, with automated violation diagnoses showing moderate-to-substantial agreement with blinded expert review. Code, benchmark prompts, evaluation scripts, and the fully de-identified HCC benchmark tables are publicly available at https://anonymous.4open.science/r/ProCARE-7E52.

Poster
Prefix Executability: Evaluating Tool-Using Agents Beyond Final Success

Amir H Rezaeian, Weiyi Sun, Yassine Benajiba, Dan Roth

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Tool-use benchmarks often score agents by final task success, but terminal outcomes can obscure whether the intermediate tool-call trajectory was executable. We propose prefix executability as a trajectory-level evaluation protocol for tool-using agents. The protocol measures whether every prefix of a predicted tool-call sequence remains executable under tool schemas, state preconditions, and data dependencies, and summarizes reliability using Prefix Executability Curves (PEC), First-Error Depth (FED), Trajectory Executability Rate (TER), horizon-normalized AUC-PEC, and Recovery Rate (RR). We instantiate the protocol on stratified samples from BFCL-v3 multi-turn and ToolSandbox. Across both benchmarks, outcome-only and prefix-level rankings diverge: agents whose execution is conditioned on an unverified plan often achieve higher point-estimate final success than non-plan-conditioned baselines while substantially lowering TER and AUC-PEC. These divergences are precisely the failure modes that prefix executability is designed to expose: they reveal whether apparent success rests on an executable trajectory, where invalidity first enters, and whether success follows recovery from an earlier failure. As a validation intervention, explicit pre-execution plan checking reverses much of this prefix-reliability loss, consistently improving executable-prefix survival while maintaining competitive terminal success. These results show that final success alone is insufficient for evaluating tool-use agents and that prefix-level executability provides an actionable reliability signal for comparing agents, diagnosing failures, and assessing validation mechanisms.

Poster
Preconditioned Flow Matching

Shadab Ahamed, Eshed Gal, Md. Shahriar Rahim Siddiqui, Simon Ghyselincks, Moshe Eliasof, Eldad Haber

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Flow matching (FM) learns vector fields by regressing stochastic velocity targets along intermediate distributions $p_t$. We identify a geometric optimization bottleneck in this regression problem: when the covariance $\Sigma_t$ of $p_t$ is ill-conditioned, gradient-based training rapidly fits high-variance directions while making slow progress along low-variance ones. In an exactly solvable Gaussian setting, we prove that the excess risk is weighted by $\Sigma_t$, and that both gradient descent and stochastic gradient descent inherit condition-number-dependent convergence. We then extend the analysis to Gaussian mixtures, showing that multimodality does not average away this effect; instead, the slowest and worst-conditioned component can control optimization. Motivated by this analysis, we propose \emph{preconditioned flow matching}, a precondition-then-match framework that transforms the target distribution into a more isotropic representation, trains the main flow in the transformed space, and maps generated samples back through the inverse transformation. We show theoretically that preconditioning reshapes the intermediate FM path and improves its conditioning. Across controlled Gaussian and Gaussian-mixture experiments, latent MNIST and other high resolution image datasets up to $512{\times}512$ resolution, preconditioning improves path-conditioning diagnostics, low-eigenvalue recovery, FID, MMD, precision, and recall. Compute-matched baselines and preconditioner-quality ablations further show that the gains are not explained merely by additional preconditioner parameters, but by improved geometry of the downstream flow matching problem.

Poster
Precise Debugging Benchmark: Is Your Model Debugging or Regenerating?

Miaosen Chai, Wang Bill Zhu, Shangshang Wang, Yejia Liu, Song Bian, Honghua Dong, Willie Neiswanger, Robin Jia

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Unlike code completion, debugging requires localizing faults and applying targeted edits. We observe that frontier LLMs often hack unit tests by regenerating correct but over-edited solutions during debugging. To evaluate how far LLMs are from precise debugging, we introduce Precise Debugging Benchmarking (PDB), a general, dataset-agnostic framework that converts any coding dataset into a debugging benchmark with precision-aware evaluation. PDB generates buggy programs by synthesizing verified atomic bugs and composing them into multi-bug programs. We define two novel metrics, edit-level precision and bug-level recall, which measure how many necessary edits are made and how many bugs are resolved. We release two evaluation benchmarks: PDB-Single on single-line bugs and PDB-Wild on multi-line and repository-level bugs. Experiments show that frontier models, such as GPT-5.1-Codex and DeepSeek-V3.2-Thinking, achieve unit-test pass rates above 76% but exhibit precision below 45%, even when explicitly instructed to perform minimal debugging on single-line bugs. Iterative and agentic debugging strategies do not substantially improve precision or recall, highlighting the need to rethink post-training pipelines for coding models.

Poster