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Large language model agents are increasingly deployed as multi-agent systems rather than as a standalone model operating within a single context. Recent agent harnesses allow the model to instantiate worker agents and to author the executable workflow that coordinates them, shifting the design of system structure from developers to the model at run time. The quality of this organization therefore constitutes a distinct capability, yet existing benchmarks either measure end-to-end task completion or evaluate coordination under structures specified in advance. We formalize this capability as workflow orchestration and introduce WorkflowArena, a benchmark of 145 long-horizon tasks spanning 8 professional domains, from software engineering and formal mathematics to legal analysis and 3D production. Each task specifies an initial workspace and an integrated deliverable composed of interdependent components, which is assessed by a hidden verifier. Agents determine autonomously whether and how to delegate, and all delegation is recorded, enabling joint evaluation of deliverable quality and the organization of the underlying work. Experiments with nine models show that no single configuration performs best across all domains and that systems exhibit distinct delegation strategies: at high effort, Claude models in Claude Code invoke workflows less frequently but with larger worker groups, whereas GPT models in Codex delegate more frequently in smaller units. When the executing model is held fixed on a challenging subset of tasks, workflows authored by Claude Opus 5.5 substantially improve weaker executors, indicating that workflow organization is itself a measurable determinant of task performance.

Low-Rank Adaptation (LoRA) is the standard paradigm for customizing large language models, yet third-party LoRA adapters pose a supply-chain risk: modifying less than 1% of model parameters suffices to implant stealthy backdoors. Recent defenses project adapter weights onto estimated backdoor subspaces, reporting near-zero static Attack Success Rates (ASR). We audit subspace-projection defenses across four model scales (Qwen2.5-0.5B/1.5B/3B/7B) and three architectures (Qwen2.5, InternLM2.5, Spark). Constructively, module-wise rank-1 trigger-difference projection (k=1, alpha=1) reduces ASR from 60.4% to 0.0% on standard benchmarks and from 70.3% to 0.0% on a 1,000-sample uncontaminated suite (p = 3.055e-299, instruction-level p = 9.49e-16) in under 5 seconds end-to-end, and we prove via a spectral-gap bound why trigger-free calibration with benign polite suffixes aligns with u1(B) (median cosine 0.9048) and achieves 0.0% ASR without prior trigger knowledge. Our main contribution is a negative finding: static ASR reduction does not imply parameter erasure. Under 5-sample few-shot reactivation, every evaluated weight-editing defense rebounds (91.7%-100.0% ASR in 1 epoch for standard projections, Fine-Pruning, ANP, SVD truncation and Li & Kim's dual-end projection; 48.7% for our single-round dual variant), all reaching 100.0% by Epoch 2, with first-epoch loss up to 5.7x lower than training from scratch. Using an exact spectrum-preserving Haar orthogonal rotation control (Frobenius norm 10.0928 preserved to 1.70e-6) and N=1..6 cumulative Gram-Schmidt basis ablation, we decompose reactivation into residual trigger-difference coupling energy at Epoch 1 (Spearman rho = 0.986), base-model learnability at Epoch 2 (100%), and benign semantic direction conflict (41.7%).

While large-scale pretraining has revolutionized language modeling, its potential remains underexplored in healthcare with structured electronic health records (EHRs). We present RAVEN, a novel generative pretraining strategy for sequential EHR data based on Recurrence-Aware next-Visit EveNt prediction. Leveraging a dataset of over one million unique individuals, our model learns to autoregressively generate tokenized clinical events for the next visit conditioned on patient history. We introduce regularization on predicting repeated events and highlight a key pitfall in EHR-based foundation model evaluations: repeated event tokens can inflate performance metrics when new onsets are not distinguished from subsequent occurrences. Furthermore, we empirically investigate the scaling behaviors in a data-constrained, compute-saturated regime, showing that simply increasing model size is suboptimal without commensurate increases in data volume. We evaluate our model via zero-shot prediction for forecasting the incidence of a diverse set of diseases, where it rivals fully fine-tuned representation-based Transformer models and outperforms both standard simulation-based next-token approaches and a prompted medical large language model baseline. Finally, without additional parameter updates, we show that RAVEN can generalize to an external patient cohort under lossy clinical code mappings and feature coverage gaps.

Robot-use Agents (RUAs) have shown promising zero-shot manipulation capabilities, but reliance on frontier, proprietary models limits research into further training. To democratize RUA research, we introduce uni-robot-agent, a unified harness for competitive open-weight robot use that supports further training. Without privileged inputs, an out-of-the-box Qwen3.8-Flash-Next achieves a RoboDojo Score of 31.39, surpassing the published GPT-6 Astra-RoboProbe result of 28.97 and many VLA/WAM baselines, and performs competitively on 19 real-world tasks. Our analysis across model generations, families, and sizes links effective robot use to four general capabilities, suggesting that future RUA training should develop them jointly.