Markdown, XML, JSON, whatever

When I started writing requests, I used Yaml because I used it every day with the home assistant. Ok I didn't see a lot of people who used Yaml and there were some formatting complications. I then switched to the Markdown. Better, but I lead experience with 2 problems. 1. Sometimes the LLM do not recognize the input prompt sections properly from the examples and the output formatting. 2. Sometimes when I copy+insert the formatting, rejects. I started to mix JSON and XML and yes ... so, for those of them who structure their input requests, what do they use?