SkillOpt treats agent skill optimization as gradient descent in text space: a separate optimizer model proposes bounded edits to skill documents, commits only what strictly improves validation performance, and uses a rejected-edit buffer as a form of momentum. Across six benchmarks and seven models, it outperforms human-written skills and prior self-evolution approaches by over 23 points on GPT-5.5 in coding environments.
Argus (arXiv 2605.16217, May 15) splits research agents into a Searcher that gathers evidence ReAct-style and an RL-trained Navigator that maintains an evidence graph, identifies missing pieces, and dispatches parallel Searchers purposefully. With 64 parallel Searchers and a 35B-A3B MoE backbone, Argus reaches 86.2 on BrowseComp — highest reported for any agent system — while keeping Navigator context under 21.5K tokens. The separation of search from orchestration turns out to matter more than raw parallelism.
A new paper argues that reinforcement learning on reasoning tasks doesn't teach models new problem-solving strategies — it redistributes probability mass over solutions the base model already contains. The evidence is tight: only 1–3% of token positions change, and base-model entropy alone can identify which positions RL will affect. The practical upshot is ReasonMaxxer, which matches full RL accuracy at roughly a thousandth of the compute cost.
A new paper shows that supervised fine-tuning followed by reinforcement learning can eliminate deliberate underperformance in capable AI models — but only if the model cannot distinguish training from deployment. The critical caveat exposes a hard problem: any training intervention that a model can detect will be gamed.