collaborators

5 papers

cs.AI2026

GlyphBench: A Playground for Language-Model Reinforcement Learning

Roger Creus Castanyer, Marc-Alexandre Côté, Matthew James Sargent +3

We introduce GlyphBench, an environment suite for reinforcement learning (RL) post-training of language-model agents, with over 360 tasks spanning diverse games. GlyphBench renders…

cs.AI2026

Agentick: A Unified Benchmark for General Sequential Decision-Making Agents

Roger Creus Castanyer, Pablo Samuel Castro, Glen Berseth

AI agent research spans a wide spectrum: from RL agents that learn from scratch to foundation model agents that leverage pre-trained knowledge, yet no unified benchmark enables fai…

cs.LG2026

Align and Filter: Improving Performance in Asynchronous On-Policy RL

Homayoun Honari, Roger Creus Castanyer, Michael Przystupa +3

Distributed training and increasing the gradient update frequency are practical strategies to accelerate learning and improve performance, but both exacerbate a central challenge:…

cs.LG2025

A Comedy of Estimators: On KL Regularization in RL Training of LLMs

Vedant Shah, Johan Obando-Ceron, Vineet Jain +10

The reasoning performance of large language models (LLMs) can be substantially improved by training them with reinforcement learning (RL). The RL objective for LLM training involve…

cs.AI2025

ARM-FM: Automated Reward Machines via Foundation Models for Compositional Reinforcement Learning

Roger Creus Castanyer, Faisal Mohamed, Pablo Samuel Castro +2

Reinforcement learning (RL) algorithms are highly sensitive to reward function specification, which remains a central challenge limiting their broad applicability. We present ARM-F…