Text and language model news — Page 36

Language models and text-based AI systems, including reasoning, generation, and understanding of written language.

ResearchOfficialarXiv Computation and Language

The Severance Problem: LLMs Lack User Representation Beyond the Prompt

A new preprint introduces the 'Severance Problem,' highlighting that large language models (LLMs) do not explicitly represent what they do not know about users beyond the immediate prompt. The authors propose the 'Severance Schema,' a method that structures the model's ignorance about the user along several dimensions. Empirical tests across five model families show that this schema reduces undesirable behaviors such as sycophancy, harmful advice, and hallucination, and encourages models to ask clarifying questions when user information is missing.

Why it matters: This work proposes a practical method to address a core limitation in personal AI assistants, potentially improving their safety and reliability.

Policy & SafetyOfficialarXiv Cryptography and Security

Decoupled Alignment Method Boosts LLM Safety Without Retraining

A new preprint introduces a training-free method to enhance the safety alignment of large language models (LLMs) during downstream adaptation. By using knowledge distillation and model fusion, the approach corrects 'shadow alignment' issues without requiring supervised fine-tuning or reinforcement learning. Experiments show an average 14.42% improvement in defense success rate across 17 LLMs, with no loss in model performance.

Why it matters: This plug-and-play technique addresses a key challenge in safely adapting LLMs for new tasks, offering a practical solution without the need for costly retraining.

ResearchOfficialarXiv Cryptography and Security

LLM Agent SLYP Discovers 39 Zero-Day Vulnerabilities in Commercial Binaries

Researchers introduced SLYP, a REACT-style pipeline leveraging LLM agents for end-to-end vulnerability discovery in commercial off-the-shelf (COTS) binaries. SLYP identified all 64 vulnerable entry functions in a 20-object COM benchmark and generated debugger-verified proof-of-concept crashes for 67.5% of cases, outperforming default production agents. To date, SLYP has uncovered 39 zero-day vulnerabilities, with 23 assigned CVEs and $203,000 in bounty awards.

Why it matters: This work demonstrates a significant advance in automated vulnerability discovery, showing that LLM agents can effectively analyze and reason about vulnerabilities in stripped, optimized machine code where source code is unavailable.

ResearchOfficialarXiv Computation and Language

AI-Generated Feedback in EFL Writing: Low Alignment Between Expert Ratings and Student Perceptions

A study deployed large language model (LLM)-based written corrective feedback in a university-level English as a Foreign Language (EFL) class with nearly 2,000 students, collecting over 20,000 essay drafts. The research found that intrinsic evaluations by expert teachers showed low alignment with extrinsic student feedback and engagement metrics. These results indicate that expert ratings may not fully capture the usefulness or impact of AI-generated feedback from the learner's perspective.

Why it matters: This research challenges the assumption that expert evaluation alone is sufficient for assessing AI-generated educational feedback, emphasizing the need to incorporate learner perspectives.

ResearchOfficialarXiv Computation and Language

OmniaBench: New Benchmark Evaluates General AI Agents Across Diverse Scenarios

Researchers have introduced OmniaBench, a benchmark designed to evaluate general AI agents across a wide range of scenarios with explicit state spaces. The benchmark spans 90 level-1 and 354 level-2 domains, covering consumer, business, and enterprise contexts, and includes 1,431 tasks. Leading AI models such as Claude-Sonnet-5 and GPT-5.6-Sol achieved only 58.54% and 57.14% Overall Pass@1 scores, highlighting ongoing challenges in planning and adaptive correction.

Why it matters: OmniaBench offers a comprehensive and diagnostic tool for systematically assessing the capability boundaries of general AI agents across heterogeneous real-world applications.

ResearchOfficialarXiv Computation and Language

MamaBench: Benchmarking LLM Robustness in Maternal and Child Health Diagnosis through Counterfactual Clinical Perturbation

Researchers introduce MamaBench, the first counterfactual benchmark for maternal and pediatric AI, comprising 434 expert-authored clinical narratives in 217 pairs across 371 pathologies. They propose Evidence-Anchored RAG (EA-RAG), a retrieval method that reduces the Bias Trap Rate (BTR) to 20.3% on Claude Sonnet 4.6—a 5.5 percentage point improvement—without degrading base accuracy. The study finds that standard medical benchmarks overstate LLM robustness by 16-28 percentage points, and that counterfactual robustness remains a significant challenge.

Why it matters: This work exposes critical gaps in current medical AI evaluation and introduces new tools for assessing and improving LLM robustness in clinical settings.

ResearchOfficialarXiv Computation and Language

SEED: Self-Evolving On-Policy Distillation for Agentic Reinforcement Learning

Researchers introduce SEED, a framework that transforms completed on-policy trajectories into hindsight skills and distills these into the policy model to enhance agentic reinforcement learning. SEED provides dense token-level supervision in addition to outcome-based RL, and experiments demonstrate consistent improvements in performance and sample efficiency on both text-based and vision-based tasks. The approach also shows robust generalization to unseen scenarios.

Why it matters: SEED narrows the supervision gap in outcome-based RL by generating and distilling reusable skills, leading to improved sample efficiency and generalization for agentic tasks.

ResearchOfficialarXiv Computation and Language

Semantic Register Compression in Multi-Agent LLM Cascades

Researchers introduce and characterize 'semantic register compression' as a measurable failure mode in multi-agent LLM systems, where intermediate agents can systematically reduce the semantic distinctions necessary for accurate downstream decisions. In a three-agent pipeline, they find that critical evaluation reduces label separability by up to 41.7% in fact-checking, 27.2% in sentiment analysis, and 20.0% in medical triage tasks. The study demonstrates that this phenomenon is generalizable across domains and is primarily driven by oriented semantic transformation, with implications for the safety and reliability of multi-agent LLM deployments.

Why it matters: This work identifies a generalizable and quantifiable risk in multi-agent LLM systems that could impact the reliability of applications in high-stakes areas such as fact-checking and medical triage.

ResearchOfficialarXiv Computation and Language

Latent Trajectory Discrimination for AI-Generated Text Detection

Researchers introduce Geometric Trajectory and Contrastive Learning (GTCL), a framework that approaches AI-generated text detection by modeling the evolution of textual representations across a sequence, rather than treating documents as static entities. GTCL segments documents into ordered local units, encodes them, and applies contrastive learning to distinguish between latent generation trajectories. Experimental results on multiple benchmarks indicate that GTCL consistently outperforms existing detection baselines.

Why it matters: This work offers a dynamic approach to AI-generated text detection, potentially enhancing robustness against evolving generative models.

Policy & SafetyOfficialarXiv Computation and Language

AI Detection Models May Misclassify Autistic Writing as AI-Generated

A preprint study analyzing around 60,000 Reddit posts found that OpenAI's GPT-2 detection model flagged a significantly higher proportion of texts from likely-autistic authors as AI-generated, even though less than 2% of posts from either group were flagged overall. The study notes that the overlap between features of autistic writing and AI-generated text is not straightforward, but the observed bias raises ethical concerns about the use of such detection models, especially in academic settings.

Why it matters: The findings highlight a potential bias in AI detection tools that could unfairly impact autistic writers, underscoring the need for careful evaluation of these models in high-stakes environments.

ResearchOfficialarXiv Computation and Language

ReportMedSAM: Guiding Medical Image Segmentation Through Radiology Reports

ReportMedSAM introduces a framework for medical image segmentation that leverages free-form radiology reports by replacing discrete extraction with a learnable concept bank. The system aligns organ-level embeddings with clinical corpora using contrastive learning and employs a frozen medical vision-language encoder. It dynamically activates task-specific Mixture-of-Experts modules based on report content, enabling robust segmentation and easy extension to new tasks without retraining existing components. Evaluation on the AbdomenAtlas 3.0 dataset shows competitive segmentation accuracy and effective handling of linguistic variability in clinical reports.

Why it matters: This approach advances scalable and robust medical image segmentation directly from natural language reports, addressing limitations of prior rule-based or phrase-matching methods.

ResearchOfficialarXiv Computation and Language

Prefill Jailbreak Bypasses LLM Refusal in Early Response; Harm Representation Unchanged

A new preprint demonstrates that inserting a simple prefill phrase (such as "Sure, here is") at the start of a prompt can bypass refusal mechanisms in aligned large language models (LLMs). The study finds that while the model's internal representation of harm remains high, behavioral refusal drops to chance, and this effect is localized to the first half of the response. The underlying mechanism is shown to be generic autoregressive conditioning rather than a safety-specific suppression, and the vulnerability is consistent across multiple model families and sizes.

Why it matters: This work exposes a structural vulnerability in current LLM safety alignment, highlighting the challenge of defending against response-site attacks that exploit generic model mechanisms rather than safety-specific features.

Policy & SafetyOfficialarXiv Cryptography and Security

AI Coding Agents Vulnerable to Supply-Chain Attacks via Setup Documentation

A new preprint demonstrates that AI coding agents can be compromised by malicious instructions embedded in project setup documentation, such as README files. The study systematically evaluates supply-chain attacks delivered through documentation across multiple ecosystems (npm, Cargo) and agent harness-model combinations, showing that agents often install untrusted or vulnerable dependencies. Security-oriented prompts only partially mitigate these risks, and the effectiveness of defenses varies by harness and model.

Why it matters: This exposes a critical security vulnerability in AI coding agents, where project documentation can be weaponized as an attack vector, threatening software supply chain integrity.

ResearchOfficialarXiv Cryptography and Security

PA-HDP: Dynamic Privacy Protection for RAG Under Query-Driven Risks

A new framework, PA-HDP, is proposed to address privacy risks in retrieval-augmented generation (RAG) systems by recognizing that privacy leakage is dynamic and depends on the user's query. PA-HDP uses a prompt-aware risk hierarchy and adaptive protection mechanisms to assess and mitigate privacy risks on a per-query basis. Experimental results show that PA-HDP reduces privacy leakage and maintains retrieval quality better than previous static, document-level approaches.

Why it matters: This work introduces a more nuanced and effective approach to privacy in RAG systems by adapting protection to the actual sensitivity of content in response to specific user queries.

ResearchOfficialarXiv Computation and Language

Answer-Conditioned Chains of Thought Degrade Verifiable-Reasoning Distillation in Large Language Models

A new preprint demonstrates that generating chains of thought conditioned on the correct answer can significantly degrade the quality of reasoning data used for distilling large language models (LLMs). The study finds that this approach can reduce verifiable-reasoning accuracy by up to 27 points on the hardest problems, and that standard correctness filtering fails to detect the degradation. The authors recommend generating answer-blind chains of thought to avoid introducing hidden flaws into reasoning data.

Why it matters: This result challenges a common practice in LLM reasoning distillation and highlights the risk of introducing subtle but significant flaws when conditioning on answers.

ResearchOfficialarXiv Computation and Language

PReM: Learning What to Preserve and When to Refresh for Context Compression

PReM is a context-compression framework for language models that maintains long context as internal layer-wise key-value (KV) memory, learning dynamically what information to preserve and when to refresh it. The approach introduces a dedicated memory layer and a special memory token, trained using Phase-Separated Refresh Training to align memory selection with generation needs. Experiments on 32K-token contexts demonstrate that PReM outperforms strong baselines at 16x and 32x compression, achieving a favorable balance between answer quality and inference efficiency.

Why it matters: This work offers a novel approach to efficient long-context inference by enabling dynamic adaptation of compressed context, potentially improving both quality and efficiency in large language models.

ResearchOfficialarXiv Computation and Language

Digital Pantheon: Simulating and Auditing Coalition Formation with LLM Agents

Researchers introduce a multi-agent framework that combines Supervised Fine-Tuning (SFT), Direct Preference Optimization (DPO), and Retrieval-Augmented Generation (RAG) to simulate political coalition negotiations using large language models. Applied to the 2019 Flemish election, the system produces stable coalition rankings and uses a novel tracing method to link agreement clauses back to party manifestos. The framework also benchmarks simulated agreements against real-world outcomes, offering a transparent and interpretable approach to studying party compatibility.

Why it matters: This work provides a transparent and scalable method for simulating and auditing political negotiations with LLMs, potentially advancing computational political science research.

ResearchOfficialarXiv Computation and Language

Reasoning Graphs Enhance Robustness of LLM Authorship Attribution

A new method uses graph neural networks to analyze reasoning structures extracted from LLM-generated text for authorship attribution. This approach significantly outperforms traditional baselines, achieving up to 27 percentage points higher accuracy under obfuscation attacks such as paraphrasing and backtranslation, and 19 points higher on texts from previously unseen model versions.

Why it matters: The method offers a more robust solution for detecting LLM-generated text, addressing vulnerabilities of existing techniques to paraphrasing and model updates.

ResearchOfficialarXiv Cryptography and Security

FlowGuard: Evidence-Grounded Security Detection for MCP Interactions

FlowGuard is a new security detection system for the Model Context Protocol (MCP) that combines semantic analysis with runtime evidence to assess risks in LLM agent tool interactions. In evaluations on an executable benchmark of 1,880 MCP cases, FlowGuard achieved F1 scores of 0.879 and 0.942 for Command Injection and File System Access vulnerabilities, respectively. It also reduced end-to-end latency by up to 2.23x compared to existing dynamic scanners and reported 523 findings across 326 real-world servers.

Why it matters: FlowGuard addresses a critical gap in MCP security by reliably detecting both execution-based and semantic risks in LLM agent tool interactions, improving upon the limitations of current scanners.

ResearchOfficialarXiv Cryptography and Security

Fully Automated End-to-End Adversary Emulation from MITRE ATT&CK-Based Cyber Threat Intelligence Using LLMs

Researchers have developed a fully automated framework that uses large language models (LLMs) to generate, execute, and revise adversary emulation playbooks directly from MITRE ATT&CK-aligned cyber threat intelligence (CTI) reports. The system unifies playbook generation, execution, and failure recovery, eliminating the need for manual intervention present in previous approaches. In evaluations on 11 CTI reports using four leading LLMs, the framework achieved its best performance with Claude Sonnet 4.5, reaching 84.22% execution success after revision and a CTI F1 score of 60.50%. The failure recovery mechanism improved execution success rates by 14.59 to 17.23 percentage points across all tested models.

Why it matters: This work represents a significant advance in automated cybersecurity testing, enabling more scalable and responsive adversary emulation by minimizing manual effort.