From PDF to Dataset: Semi-Automated Extraction of Fine-Tuning Data

Abstract

Preparing fine-tuning datasets for large language models (LLMs) commonly involves substantial manual effort, particularly in extracting, structuring, and validating data from unstructured sources. This study proposes a semi-automated, human-in-the-loop approach for generating fine-tuning question-answer (QA) pairs from PDF documents. The research investigates how unstructured textual content can be systematically transformed into validated QA data suitable for fine-tuning, while mitigating the risks associated with hallucinated or low-quality model outputs.The proposed system consists of a web-based architecture combining a React frontend with a Flask backend interfacing with the OpenAI API. Users provide a PDF document and a target page range, after which the system extracts text and generates candidate QA pairs. These candidates are presented for manual inspection, filtering, and refinement, prior to export in a structured JSON format compatible with fine-tuning pipelines.The results indicate that the proposed approach reduces the effort required for manual dataset construction while preserving data quality through mandatory human validation. The study highlights the effectiveness of hybrid automation workflows in accelerating fine-tuning dataset preparation without compromising reliability, and contributes design insights for human-centered tools supporting LLM customization.