How would I check the type of model the player is using?

So in my mod, I'm making armor that fits to the players skin. I never liked how bulky armor in Minecraft is. I mean, it worked for literal armor, but if you're trying to make the amor look like an outfit, it just doesn't work, so I wanted to make thin armor, but the problem is, what if the player is using an Alex model, the three pixels arm length. Personally, I like Alex's model better, so I don't think it would work for me, so I'm thinking what I should do is check if the player is using an Alex model or a Steve model, and then when it comes back true or false, the crafting recipe will give them the corresponding one. If you have any other suggestions on how to do this, please share them. Hope this makes sense. Anyway, thanks in advance!