title_body: How to stamp text to PDF, with a twist
upvoted_answer: Maybe I don't understand the question, but if you can already do the job with SetaPDF-Stamper manually then all it takes is a little PHP code to do it automatically. There literally is no easier solution to your problem as described; to automate it will take custom code, period, and SetPDF-Stamper is the kind of library you would need for that purpose.