Compliance with the European Union’s Platform-to-Business (P2B) Regulation is challenging for online platforms, and assessing their compliance can be difficult for public authorities. This is partly due to the lack of automated tools for assessing the information (e.g., software documentation) platforms provide concerning ranking transparency. Our study tackles this issue in two ways. First, we empirically evaluate the compliance of six major platforms (Amazon, Bing, Booking, Google, Tripadvisor, and Yahoo), revealing substantial differences in their documentation. Second, we introduce and test automated compliance assessment tools based on ChatGPT and information retrieval technology. These tools are evaluated against human judgments, showing promising results as reliable proxies for compliance assessments. Our findings could help enhance regulatory compliance and align with the United Nations Sustainable Development Goal 10.3, which seeks to reduce inequality, including business disparities, on these platforms. The study claims the “Available” and “Reusable” badges, indicating its accessibility and applicability for further research and practical use. The technological expertise required for reviewers includes proficiency in Python and Bash scripting. For optimal performance, running the research artifact necessitates specific system specifications. It is tested and recommended on Linux operating systems, particularly Debian, and macOS. Additionally, Python version 3.7 or newer is required to ensure compatibility and full functionality of the tools developed in this study.