When trying to collect information by SNMP get, the "description" field comes truncated.
Description strings comes truncated (cutted in the edges).
There is no handling process. It's a software limitation that should be respected. Description should not have more than 64 character.
When configuring the description field inside a router interface, we can put a big description with a lot of characters but when trying to collect it via snmp get, the router only sends the first 64 characters, what turns description bigger than that truncated.
Try always to set the description field as short as possible.