Two ways to handle this in my mind:So I was looking at the thief archetype for the rogue and my question is, would it break anything if a rogue with leatherworker tools could make boots that make you auto succeed against ball bearings. I find it odd that the thief screws his allies and his enemies by using caltrops and ball bearings.
First magic boots, which the rogue might be able to craft with some help according to the rules in XGE. That is going to be costly in time and money.
The second is a custom spell. I could see a cantrip that grants immunity to ball bearing or caltrops until your next turn. Or a 1st-level spell that does the same for up to 4 people for a minute with concentration. I would make it specific to these two things though, if it granted immunity to similar effects like grease or ice it would need to be a higher level spell IMO.
The rogue himself could take magic initiate to pick up the spell or cantrip.