Agentic data science solutions often contain methodological failures A study of 220 data science tasks found that most agentic data science solutions contained at least one methodological failure, such as data leakage or improper validation, regardless of the agent harness or model strength used. The research, posted on arXiv, also found that data leakage correlated positively with reported accuracy, meaning accuracy-only evaluations can reward broken pipelines. The authors conclude that teams shipping data science agents need explicit leakage and validation checks because high benchmark scores are masking silent methodological errors. arXiv https://arxiv.org/abs/2610.14115 Agentic data science solutions often contain methodological failures Which summary reads better? Pick one — models revealed after.Both summaries are AI-generated. Across 220 data science tasks, most agentic DS solutions contained at least one methodological failure—data leakage, improper validation—regardless of harness or model strength, and leakage actually correlated positively with reported accuracy. Your accuracy-based evals are actively rewarding broken pipelines; if you're shipping DS agents, you need explicit leakage/validation checks because high benchmark scores are masking silent methodological errors, not confirming correctness. Across 220 data science tasks, most agent-generated solutions had at least one methodological failure even when produced by stronger models or more complex agent harnesses. Accuracy-only evals are actively misleading here: data leakage can improve predictive scores, so production DS agents need explicit checks for leakage, validation design, and domain-methodology errors before their outputs are trusted or benchmarked.