What is this functionality of emacs/Doom/evil/cider of keeping prompting "Lisp expression:" when typing in evil input mode?

Questions & Help Troubleshooting
15

I’ve taken a look at symex.el. I like it being conceptually clean.
But I find the extra mode of symex a hurdle in addition to the evil’s normal mode, and input mode.
I’d rather have lispy to help in the input mode.