Gunslinger, Tinkerer’s tool check to repair a jam, do you add anything other than proficiency?

question about the gunslinger. For the tinkerer’s tool check to repair a jam, do you add anything other than proficiency (dex or int mod) to you roll? Generally, depending on the nature of the repair, it would be Proficiency + Dex or Int mod.

— Matthew Mercer (@matthewmercer) April 15, 2018