LongDA: Benchmarking LLM Agents for Long-Document Data Analysis
Yiyang Li, Zheyuan Zhang, Tianyi Ma, Zehong Wang, Keerthiram Murugesan, Chuxu Zhang, Yanfang Ye
TL;DR
LongDA targets the evaluation of LLM agents in documentation-intensive data analysis by grounding tasks in real, large-scale government datasets and long unstructured documentation. It introduces LongTA, a tool-augmented ReAct-style framework, and constructs 505 reproducible queries from 17 national surveys to probe retrieval, reasoning, and code execution within strict constraints. The study reveals substantial performance gaps across state-of-the-art models, with success hinging primarily on information retrieval and tool-use strategies rather than pure reasoning, underlining the challenges of long-context, document-grounded analytics. The results motivate focused advances in document navigation, content integration, and reliable tool orchestration to enable robust decision support in real-world analytical settings.
Abstract
We introduce LongDA, a data analysis benchmark for evaluating LLM-based agents under documentation-intensive analytical workflows. In contrast to existing benchmarks that assume well-specified schemas and inputs, LongDA targets real-world settings in which navigating long documentation and complex data is the primary bottleneck. To this end, we manually curate raw data files, long and heterogeneous documentation, and expert-written publications from 17 publicly available U.S. national surveys, from which we extract 505 analytical queries grounded in real analytical practice. Solving these queries requires agents to first retrieve and integrate key information from multiple unstructured documents, before performing multi-step computations and writing executable code, which remains challenging for existing data analysis agents. To support the systematic evaluation under this setting, we develop LongTA, a tool-augmented agent framework that enables document access, retrieval, and code execution, and evaluate a range of proprietary and open-source models. Our experiments reveal substantial performance gaps even among state-of-the-art models, highlighting the challenges researchers should consider before applying LLM agents for decision support in real-world, high-stakes analytical settings.
