How do I add job descriptions to the promotion notification?

This is new to me but I've been perusing tutorials and the career_level and career_reward XML files, as well as reading string tables. I'm not finding any answers about this, and I'm thinking it'd be very simple for someone here to point me to the right place.

I want to add the built in job descriptions to job promotion notification windows--how the previous Sims games had it. Any help with this is appreciated. Do I even need to edit string tables?

Also, is there any efficient means of doing this in bulk, or would I have to go file by file for each career level and do this manually?