I like this idea, sort of like Infiltrator actions to a lesser extent, only instead of getting stabby on a fellow noble, you're getting stabby on that merchant (and then sorting through his pockets afterward). Perhaps the actions can be based off the same skills.
I don't see why it should be limited as suggested though, sure an individual's actions should have little effect on their own (much like courtiers and diplomats have little effect), but nobles can arrest adventurers for any or no reason already, if group of adventurers are causing a problem in a region any troop leading noble can swoop in and gather them up with little trouble as is. Personally I'd like to see that improved upon, maybe at higher skill an adventurer can escape or hide from a noble's troops when a noble tries to arrest them. I could see certain realms hiring such a band of "adventurers" to act as privateers, bandits, or partisans to act against other realms they may or may not actively be at war with as deniable assets (which would give Judges good reason to torture them, as proof that the adventurers are acting as agents of a realm would be good grounds for war).
