Remove tag if not in specific folder?

What kind of rule would accomplish removing a tag from files outside a specific directory? I have an inbox folder that collects things from other folders, and a hazel rule that adds a to-process tag to files in that directory so I can see them in a sidebar tag favorite.

I'd like a rule to remove this tag on files NOT in the inbox, if I forget to remove it when I file things out of the inbox.

I tried a mac-hdd rule with the subfoldering but never figured out a rule that would do what I wanted. I also wondered if having a rule processing the root hdd folder and continually crawling all subdirs would be too resource intensive for my MacBook anybow.

Are you filing things manually or via a Hazel rule? If the latter, you can remove the tag when you move the file. If the former, you would need to have Hazel monitor the destination of where you file it.