If that's the case, don't use anything in mIRC.
Because heaven forbid, $version might just suddenly dissapear, or $hfind, or anything else for that matter.
You do make a valid point that they may be undocumented for good reasons, yet I think you would also be a little more open minded to other possibilities, such as Khaled forgetting to put them in, or not having time to do so.
I know for sure I have a really hard time trying to remember every single detail about my script, and I also know that there are some things in my script that I purposely don't document.
Be a little more open minded