Thanks. Even though I haven't come across any responses that immediately ring a bell as to the original phrase/term that I was trying to remember, I've learned quite a bit just from looking up some of these responses.

Actually, I did not even know there was such a term as "malicious compliance", but I did this exact thing back in the day. I worked for a bank call center when I was younger, and we had these really strict guidelines for reversing fees. I hated the bank and thought they were pure evil, so I would always try to find a way to reverse as many fees as I could. anyway, I found this loophole in our very long and very specific/descriptive computerized manual. I started using the loophole exactly to the letter, and I had this manager spying on me who came over to ask me what I was doing, so I showed him in the manual where it said exactly what to do, and the look on his face was priceless. He said something along the lines of "you know exactly what you're doing".