I see that I can do something like this:
(defun limit-warnings ()
(set (make-local-variable 'warning-minimum-level) 'fatal))
(add-hook 'minibuffer-setup-hook 'disable-warnings)
(Sorry for syntax errors; I'm not very familiar with Lisp and the above is just an example.)
How do I combine that with warning options to disable warnings from only the minibuffer? (For example, the minibuffer doesn't need to tell me that I've hit the end of the buffer or that the M-x: prompt string is read-only.)
I tried describe-variable with warning-minimum-level and there was no such variable defined.