You should be able to use the callback from outside the GUI, although scripting that might be a bit tricky. I am not sure if that is why you asked about doing it without using the callback or if you had another reason.
If you can login directly to the server running the probe, you can use the Net-SNMP toolkit:
http://www.net-snmp.org/
Those tools are usually installed on Linux systems or available from the software repository for the distribution. Binaries are available for Windows at the site above.
I have used these commands on Linux and Windows, and they work great!