Waypoints - determine if location to place can be accessed by AI

[m0nkey 111]

Hello again.

This is probably a question that has an answer, but I'll be darned if I can figure out how to word it to get a search result.

Basically, if I am choosing a random position from center to put a waypoint for an AI group, how do you know if its a position that can be "moved to"?

I learned how to check if surfaceIsWater, but don't see anything else to dictate if for example the waypoint position is going to be inside a huge rock that the group will never be able to get close enough to.

Or if you know the answer but prefer to let me learn it myself, I am fine with that too. But what do I search for ;)