Does what it says on the tin!

I disagree with the comment that says this has nothing to do with SNMP. The readme file clearly indicates that the author is using the exec feature of SNMP to return the output and result codes of custom scripts. So it has everything to do with SNMP! And it does exactly what the author writes in his/her summary:

“This is a simple example of how publish the output of scripts for uptime, CPU load and available memory and disk space through SNMP and collect them with Nagios.”