The outer cap (the protective cap which covers the eyeball) which is the cap that comes off with each shed as a new outer cap forms, is very sensitive to humidity changes.

If the humidity is slightly too low, the eye can become dented or creased. Either on it's own or if the snake pushes it's eye against something.

It will not hurt the eye. It is absolutely nothing to worry about. It will always fix itself and if it doesn't, a quick misting to raise the humidity will fix it.

I'm not talking about a stuck eyecap. This is the protective outer cap which is supposed to be there. They can and do become dented with slightly low humidity. Unfortunately when people see this they often immediately think it's an old cap that is stuck and did not come off with the last shed. Then they proceed to mess with it thinking that only old caps do this but this is not true.

So again, it's nothing to worry about. Just be sure your humidity is good.