There's also the existing code at the site for reference. That's how you should be doing things. You need a really good reason to not follow the local conventio

There's also the existing code at the site for reference. That's how you should be doing things. You need a really good reason to not follow the local conventions. So, most answers you seek will be in the existing code base. Also, I would add that most mainframe programming is flat procedural (no objects, no complex data structures - heck, COBOL doesn't have real strings). So the vendor manuals cover most of what you need to know, as things don't get too complicated and obscure. And there are always colleagues to ask too.