Update customfield based on replies or comments

I am trying to build an automation capability that will parse through ticket comments upon update (reply or comment) and automatically update a customfield. For instance, if I have a customfield for Ticket Classification (spam, query, scan, etc.) and someone types in “Classification:spam” in the a reply or comment I want the customfield in the ticket to automatically change upon saving.

Has anyone worked on something like this before?

You can do this by using the following RT plugin: https://metacpan.org/pod/RT::Extension::CommandByMail#Custom-field-values

If needed, you can also write your own scrip action to parse messages and record customfield values.