ExtractBench: A Benchmark and Evaluation Methodology for Complex Structured Extraction
This provides a standardized benchmark for enterprise document extraction, addressing a critical bottleneck in deploying LLMs for real-world data processing, though it is incremental in improving evaluation methodology rather than proposing a new extraction method.
The paper tackles the problem of evaluating LLMs for PDF-to-JSON structured extraction by introducing ExtractBench, a benchmark and evaluation framework that addresses gaps in schema breadth and semantic scoring, revealing that frontier models fail completely on complex schemas, with 0% valid output on a 369-field financial reporting schema.
Unstructured documents like PDFs contain valuable structured information, but downstream systems require this data in reliable, standardized formats. LLMs are increasingly deployed to automate this extraction, making accuracy and reliability paramount. However, progress is bottlenecked by two gaps. First, no end-to-end benchmark evaluates PDF-to-JSON extraction under enterprise-scale schema breadth. Second, no principled methodology captures the semantics of nested extraction, where fields demand different notions of correctness (exact match for identifiers, tolerance for quantities, semantic equivalence for names), arrays require alignment, and omission must be distinguished from hallucination. We address both gaps with ExtractBench, an open-source benchmark and evaluation framework for PDF-to-JSON structured extraction. The benchmark pairs 35 PDF documents with JSON Schemas and human-annotated gold labels across economically valuable domains, yielding 12,867 evaluatable fields spanning schema complexities from tens to hundreds of fields. The evaluation framework treats the schema as an executable specification: each field declares its scoring metric. Baseline evaluations reveal that frontier models (GPT-5/5.2, Gemini-3 Flash/Pro, Claude 4.5 Opus/Sonnet) remain unreliable on realistic schemas. Performance degrades sharply with schema breadth, culminating in 0% valid output on a 369-field financial reporting schema across all tested models. We release ExtractBench at https://github.com/ContextualAI/extract-bench.