Fred Sala

Existing computer-use benchmarks fail to capture the realism, complexity, and long-horizon demands of real-world computer use, limiting their ability to reveal the limita-tions of frontier agents. We introduce OSWORLD 2.0, a benchmark of 108 long-horizoncomputer-use workflows across everyday and professional tasks, designed to capturecomplex and challenging real-world phenomena. Each task represents a realistic end-to-end workflow that takes human users a…

Curating training data is among the most consequential yet labor-intensive parts of modern AI development: practitioners iteratively propose, implement, evaluate, and revise data policies against noisy benchmark feedback. We ask whether generalist coding agents can automate this data-curation loop. We introduce CURATION-BENCH, an agent-centric benchmark that fixes the model, training recipe, and evaluation suite while giving agents commandline access to…

Fine-tuning Large Language Models (LLMs) typically relies on large quantities of high-quality annotated data, or questions with well-defined ground truth answers in the case of Reinforcement Learning with Verifiable Rewards (RLVR). While previous work has explored the benefits to model reasoning capabilities by scaling both data and compute used for RLVR, these results lack applicability in many real-world settings where…

Rubric-based evaluation is widely used in LLM benchmarks and training pipelines for open-ended, less verifiable tasks. While prior work has demonstrated the effectiveness of rubrics using downstream signals such as reinforcement learning outcomes, there remains no principled way to diagnose rubric quality issues from such aggregated or downstream signals alone. To address this gap, we introduce RIFT: RubrIc Failure mode…

Snorkel Chief Scientist Fred Sala and Kobie Crawford chat with the Terminal-Bench team to unpack the design behind Terminal-Bench 2.0 and the new Harbor framework.

Reinforcement learning (RL) has become the dominant paradigm for improving the performance of language models on complex reasoning tasks. Despite the substantial empirical gains demonstrated by RL-based training methods like GRPO, a granular understanding of why and how RL enhances performance is still lacking. To bridge this gap, we introduce SPARKLE, a fine-grained analytic framework to dissect the effects of…

The rapid progress and widespread deployment of LLMs and LLM-powered agents has outpaced our ability to evaluate them. Hand-crafted, static benchmarks are the primary tool for assessing model capabilities, but these quickly become saturated. In contrast, dynamic benchmarks evolve alongside the models they evaluate, but are expensive to create and continuously update. To address these challenges, we develop BeTaL (Benchmark…

Evaluating the effectiveness of unlearning in large language models (LLMs) remains a key challenge, especially as existing metrics often rely on specific reference outputs. The widely used forget quality metric from the TOFU benchmark compares likelihoods over paraphrased answers but is highly sensitive to the choice of the reference answers, potentially obscuring whether a model has truly forgotten the targeted information. We…

LLM-as-a-judge—often with multiple judges—is now the standard for scalable model evaluation, yet judge biases and correlations can amplify errors. We cast aggregation as inference in a latent-factor Markov random field that jointly models a latent true-quality variable, inter-judge correlations, and confounders (e.g., generation length). We address two key technical challenges—identifiability and learning a higher-rank latent structure—via CARE, a two-stage estimator that…