how to batch rename files based on internal content (e.g., Invoice PDF to “Date_Vendor_Amount”)? [closed]

I have hundreds of PDF invoices with randomized names (e.g., inv_98234.pdf). I need to batch rename them based on the actual content inside the document, formatting them as [Date] – [Vendor] – [Amount].pdf.

I am currently testing a tool called RenomeeAi to automate this content-aware renaming. While it handles the OCR and extraction, I want to explore if there are other workflows, CLI tools, or custom scripting methods to achieve a similar result.

What are the most reliable, lightweight Python libraries or APIs for extracting structured key-value data (like invoice dates and totals) from unstructured PDFs?

Thanks for any recommendations or script examples!