There's no way to ask this IC, and I think that is well. The most we should be able to hope for IC is a progression: first you'll be able to repair these items, and then with additional practice/experience this set, and so on. You can also figure it out yourself: equip yourself with a full set of leather armor, and try to repair everything one by one. You'll know which ones you can repair, and which ones you need more training. For weapons, find the wimpiest version of the class of weapons you use (sword, axe, hammer), and move up until you can't repair anymore. That's your limit, keep using and repairing the one before that until you've got the skill to repair the next level.