Just in case, if you’ve ever wondered how to stop cron from sending empty emails, a quick look at man mail will give you the answer you’re looking for (if you know what you’re searching for):

    -E

    If an outgoing message does not contain any text in its first or only message part, do not send it but discard it silently,
    effectively setting the skipemptybody variable at program startup. This is useful for sending messages from scripts started 
    by cron(8).

I got this after visiting couple of forums, and some threads at stack exchange, however this one nailed it

So all you need to do is, fire up that crontab -e and make your script run every five minutes, without fear of the noise

*/5 * * * * /usr/local/bin/only-talk-if-there-are-errors-script |& mail -E -r $(hostname)@opensuse.org -s "[CRON][monitoring] foo bar $(date  --iso-8601='minutes')"  do-not-spam-me@example.com

Et voilà, ma chérie! It's alive!