Microsoft Research
Abstract
We introduce rStar2-Agent, a 14B math reasoning model trained with agentic
reinforcement learning to achieve frontier-level performance. Beyond current
long CoT, the model demonstrates advanced cognitive behaviors, such as thinking
carefully before using Python coding tools and reflecting on code execution
feedback to autonomously explore, verify, and refine intermediate steps in
complex problem-solving. This capability is enabled through three key
innovations that makes agentic RL effective at scale: (i) an efficient RL
infrastructure with a reliable Python code environment that supports
high-throughput execution and mitigates the high rollout costs, enabling
training on limited GPU resources (64 MI300X GPUs); (ii) GRPO-RoC, an agentic
RL algorithm with a Resample-on-Correct rollout strategy that addresses the
inherent environment noises from coding tools, allowing the model to reason
more effectively in a code environment; (iii) An efficient agent training
recipe that starts with non-reasoning SFT and progresses through multi-RL
stages, yielding advanced cognitive abilities with minimal compute cost. To
this end, rStar2-Agent boosts a pre-trained 14B model to state of the art in
only 510 RL steps within one week, achieving average pass@1 scores of 80.6% on
AIME24 and 69.8% on AIME25, surpassing DeepSeek-R1 (671B) with significantly
shorter responses. Beyond mathematics, rStar2-Agent-14B also demonstrates
strong generalization to alignment, scientific reasoning, and agentic tool-use
tasks. Code and training recipes are available at
https://github.com/microsoft/rStar.
AWorld Team
Abstract
The learning from practice paradigm is crucial for developing capable Agentic
AI systems, yet it is severely hampered by inefficient experience generation, a
bottleneck especially pronounced in complex benchmarks like GAIA. To address
this, we introduce AWorld, an open-source system engineered for large-scale
agent-environment interaction. By distributing tasks across a cluster, AWorld
accelerates experience collection by 14.6x compared to standard single-node,
sequential execution. This critical speedup makes extensive reinforcement
learning practical and scalable. Leveraging this capability, we trained a
Qwen3-32B-based agent that significantly outperforms its base model, increasing
its overall GAIA accuracy from 21.59% to 32.23%. On the benchmark's most
challenging levels, our agent achieves a score of 16.33%, surpassing the
performance of leading proprietary models. Our open-source system and resulting
agent provide a practical blueprint for a complete agentic AI training
pipeline, from efficient interaction to demonstrable model improvement.