Radius： The Radius determines how close a navigating character can get to a wall and consequently the width of the narrowest gap between two walls that can it can squeeze through.
Height：efers to the height of the “ceiling” above the navmesh surface - an area may not be reachable simply because there is not enough headroom for the character
Max Slope：parameter sets the threshold of steepness where a ramp becomes a wall
Step Height： the maximum height of bump or step in the floor surface that is ignored by the character (any step greater than this height results in a disconnected walkable area rather than a continuation of the same area).
