Research

New AI papers from arXiv, picked daily and explained with their claims, benchmark results and code.

2566 articles · page 15 of 54 · The Research front page

Agents

Faster Jev decisions do not consistently improve agent task efficiency

Ling and colleagues tested whether replacing agents’ action-selection components with Jev, a model designed for fast choices among defined options, improves end-to-end efficiency. Jev lowered decision cost and latency in all five agents, but those local gains did not reliably translate into faster or more economical successful outcomes. Mobile agents were particularly vulnerable to failed recovery and declaring completion too early.

Agents

Lightweight decision model reduces token use in multi-agent systems by up to 54.6%

Wang et al. propose Jev-LiteMAS, a multi-agent framework that allocates routine coordination to a low-cost decision model (Jev) and reserves generative models for expert execution and corrective feedback. Across four benchmarks and two backbones, the method reduces generative-LLM tokens by 12.7–54.6% with accuracy within 1.34 points of the baseline, and lowers end-to-end latency in most configurations.

Evaluation & benchmarks

Executability-oriented benchmark exposes LLM service-call grounding failures

Wang et al. introduce SCCGBench, a benchmark of 3,135 real-world RapidAPI call functions mined from GitHub, designed to test whether LLM-generated code actually invokes the correct service endpoint. They evaluate six code LLMs and find that models often generate plausible-looking but non-executable code, with the best model achieving only 3.76% Mock success (hitting the correct host, endpoint, and HTTP method) without documentation. Providing gold API documentation boosts Mock to roughly 90%, highlighting that API grounding, not code generation, is the primary bottleneck.

Theory

Hosted decision model Jev violates independence of irrelevant alternatives

Rajput et al. pre-registered and ran 299,463 API calls on Jev-1.13.0, a hosted decision model, to test whether its probabilities respect independence of irrelevant alternatives (IIA). They found systematic, directional shifts in log-odds between the correct label and its strongest rival whenever any option was added, even when that option carried less than 0.1% of the probability mass. The violations are substantial and structured, invalidating the assumption that probabilities are fixed properties of options.

Safety & security

Accessibility-based masking shields computer agents from indirect prompt injections

Seip, Markovinović and Hein introduce SA-CUA, a dual-LLM architecture for agents that operate graphical interfaces through screenshots, mouse clicks and keyboard input. In their experiments, deterministic masking based on accessibility metadata prevented untrusted free text from reaching the privileged model, while an independent verification channel preserved more task utility than the earlier CaMeL-CUA design and yielded zero successful attacks on the evaluated tasks.

Language models

General-purpose LLMs already work as Jev-style decision models out of the box

Yinheng Li and Justin Wagle present LLM2Jev, a framework that converts any causal LLM into a Jev-style decision model by scoring bracketed numeric option IDs from next-token probabilities. On frozen Qwen3.5-4B, this training-free recipe matches or exceeds community Jev-style models on the same backbone and handles multimodal decisions. Fine-tuning improves weaker models and many-option routing, but yields diminishing returns for strong backbones.

Robotics & embodied AI

Unified world action model jointly learns perception, prediction, and planning

The authors introduce P3-WAM, a unified world action model that trains 3D interaction reconstruction, action-conditioned world prediction, and joint action-future planning in one architecture. Unified training improves all three capabilities over single-mode training, and the model outperforms specialized baselines on hand reconstruction and action-conditioned video prediction across four datasets while producing goal-directed planning videos with stronger instruction adherence.

Generative media

Grounding 3D texture generation in surface-aligned material observations improves fidelity

The authors introduce SUPRA-Tex, a framework for single-image 3D generation that separates material estimation, surface alignment, and geometry-conditioned completion. It projects reference-view PBR maps into the target latent space and uses an interleaved flow transformer to complete the full surface. Trained only on public data, it matches or exceeds commercial systems on in-the-wild images.

Vision

View-decoupled geometry states improve predictive 3D world modeling

The authors propose GeoState, a view-decoupled geometry representation that disentangles scene content from camera viewpoint when using pretrained geometry foundation model (GFM) features as predictive states. By aggregating multi-view GFM features into a shared scene state and querying it only at decoding time, the model allows a temporal predictor to focus on genuine scene evolution. GeoState outperforms existing 3D world models on Waymo in depth forecasting, supports geometrically consistent cross-view queries, and generalizes zero-shot to KITTI and nuScenes.

Agents

KnowGPO aligns trajectories by knowledge for better credit assignment in search agents

The authors introduce KnowGPO, a reinforcement learning framework that assigns credit in deep search agents by representing each step's state as a subset of atomic knowledge conditions satisfied, rather than by surface observations. Trajectories with the same knowledge state are grouped for within-group comparison, and the incremental increase in satisfied conditions between steps serves as a dense process reward. On three benchmarks (Xbench, BrowseComp-ZH, GAIA), KnowGPO improves over outcome-only GRPO by 2.0 to 5.9% and exceeds recent process-supervision methods by 3.8 to 4.2 percentage points, with an 8B model matching or surpassing most 32B open-source systems.

Language models

Restricting weight updates to non-principal subspace preserves old skills while learning new ones

Chavan et al. introduce Subspace Tuning (SST), a method that restricts each weight update to the bottom singular subspace of the weight matrix, preventing changes along the principal directions. Across SFT and self-distillation, SST preserves prior capabilities (e.g., reasoning, tool use) while matching or exceeding the target-task accuracy of unconstrained fine-tuning, with 2–4× less KL divergence from the base model.

Reinforcement learning

Stochastic attention routing enables efficient RL alignment for diffusion models

The authors propose Routing Policy Optimization (RPO), a method that introduces stochastic exploration into diffusion and flow generators by randomly sampling attention routes during training while preserving the original deterministic sampler at inference. RPO uses a Gaussian velocity likelihood to score perturbations and a controlled two-rollout estimator to compute advantages, achieving better reward-aligned generation quality on text-to-image and text-to-video tasks while reducing training cost by up to 4.2x compared to Flow-GRPO.

Agents

Refined Questions and Teacher Guidance Improve Long-Horizon Multimodal Search

Zhang and colleagues present a pipeline for training multimodal agents to investigate questions through multiple rounds of web search, visual retrieval and reasoning. Their 9-billion-parameter agent improved average accuracy by 15.3 percentage points over its agentic-workflow baseline across seven primary benchmarks, with joint reinforcement learning and on-policy distillation adding 2.3 points beyond supervised fine-tuning.

Reinforcement learning

Decoupling skills from expert policies improves multi-capability vision-language model training

The authors propose SCOPED, a framework that trains separate capability-specific experts via reinforcement learning, extracts explicit skills from their reasoning trajectories, and uses those skills to condition the experts during on-policy distillation into a unified student vision-language model. Across eight multimodal benchmarks, SCOPED enables a compact 8B model to achieve the highest average score among evaluated models, surpassing both the backbone and mixed-capability RL baselines.

Vision

Privileged motion and gravity cues improve feedforward 3D reconstruction without extra test-time cost.

Qian, Ren and Bai augment feedforward transformer models for multi-view 3D reconstruction by supplying optical flow and gravity direction as privileged information during training only. Evaluated on standard benchmarks, the models show consistent gains in accuracy and robustness, especially for dynamic objects, ambiguous structure and challenging camera motion. The optimal injection stage is architecture-dependent: middle-layer integration suits VGGT, while late-stage integration suits π3.

Generative media

Feature-trained image tokens improve generation quality at lower sampling cost

Zhang Xiaofeng and colleagues separate token learning from pixel rendering: the tokenizer is trained to reconstruct semantic features, while a detached decoder converts tokens into images without letting pixel losses reshape the representation. Across four pretrained vision encoders, this produced tokens that image generators could model more effectively, improving generation quality at substantially lower sampling compute than evaluated continuous alternatives.

Efficiency & systems

KV-cache eviction method is provably near-optimal, not just heuristic

DropKV addresses the KV-cache memory bottleneck in long-context LLMs by turning the NP-hard problem of minimizing output perturbation from cache eviction into independent per-token scores. The authors prove this decoupled proxy is within a constant factor of the optimal combinatorial solution under a cone condition they verify empirically, and implement it in fused Triton kernels. Across RULER and LongBench at 5% and 10% budgets, DropKV beats existing eviction baselines in accuracy and latency.

Agents

Multimodal decision models output structured choices in a single pass

The authors introduce Intern-Decision, a family of multimodal decision models (0.8B, 2B, and 4B parameters) that reformulate structured decision making as next-token prediction over masked fields in a predefined JSON skeleton, enabling multi-field scoring in a single causal forward pass. The 4B model achieves a 90.02% unweighted average accuracy across seven evaluation suites, compared with 88.74% for the baseline Jev model, and attains a mean latency of 44.16 ms for a 289-token request with three decision fields on one RTX 4090.

Agents

KV cache substitution between frozen LLMs fails; augmentation succeeds

The authors tested eight methods for substituting a sender's KV cache into a frozen reader LLM in place of its own cache. All substitution methods performed at the level of an uninformative cache baseline, failing to improve the reader's accuracy. In contrast, an augmentation approach—where the reader retains its own cache and attends over the sender's cache as additional context, with only its queries adapted—beat the reader's native-context baseline and worked when pooling multiple senders.

Evaluation & benchmarks

LLM agents degrade reliably under controlled interaction perturbations

The authors introduce AgentPerturb, a framework that applies missing, redundant, and incorrect edits to user utterances, procedural specifications, carried-over context, and tool contracts in agentic tasks. Evaluating ten models on APEX-Agents and Toolathlon, they find consistent performance drops, with vulnerability organized more by perturbation target than type, and successful perturbed trajectories often requiring substantially more computation.

Generative media

Correcting classifier-free guidance in early steps improves image editing fidelity

Floros et al. identify a flaw in how classifier-free guidance (CFG) is applied to text-and-image-to-image (TI2I) flow matching models. They find that CFG's unconditional branch approximates the average of all possible edits, which harms source preservation during the noisy early phase of generation. They propose a simple inference-time correction: substitute a no-edit velocity into the unconditional branch for early flow steps. This intervention recovers a richer alignment-preservation tradeoff without additional model evaluations and is validated on both pixel-space and latent TI2I flows.

Agents

Localized Context Distillation resolves the learning dilemma in interaction experience

The authors introduce Localized Context Distillation (LoCD) to improve how large language models learn from interaction experience. LoCD first localizes the spans of a student trajectory that require revision, then has a teacher regenerate only those spans from the student's own prefix, and finally trains the student on the revised segments. In extensive experiments on math reasoning, code generation, and interactive agent tasks, LoCD consistently outperforms strong baselines while requiring smaller and sparser parameter updates.

Language models

Token-level teacher selection improves on-policy distillation for LLMs

The authors propose a framework for token-level teacher selection during on-policy distillation (OPD), where different teachers can supervise different tokens of a student rollout. They prove conditions for teacher-student compatibility and introduce representation-based routing, which outperforms confidence-based methods in producing diverse, high-quality student responses. Experiments across math, code, kernel generation, and visual reasoning show consistent improvements of up to 10 percentage points in pass@k over vanilla OPD and individual teacher experts.

Reinforcement learning

Adversarial rubric repair improves self-training on open-ended expert tasks

Dai et al. address a central obstacle in self-generated training for tasks without objectively checkable answers: models can exploit incomplete grading rubrics rather than produce genuinely useful work. Their Recursive Reward Improvement method adversarially tests and repairs each rubric before training, producing substantial gains on medical benchmarks and some transfer to unseen professional domains.

Code & software

8B model learns to construct and refine GPU optimization scripts, beating larger LLMs

The authors introduce a training method that teaches an 8B language model to generate complete GPU optimization scripts and improve existing ones. Trained on search-derived examples from TVM MetaSchedule, the model reaches 91.27% correctness for construction and 92.01% for refinement, and produces faster kernels than six frontier LLMs with hundreds of billions to trillions of parameters.