Among other things, a determination is made of and ability of an autonomous vehicle to safely or robustly travel a road feature or a road segment or a route that is being considered for the autonomous vehicle as of a time or range of times. The route conforms to properties of stored road network information. The road feature or road segment or route is eliminated from consideration if the computer has determined that the road feature or road segment or route cannot be safely or robustly traveled by the autonomous vehicle. The determination is based on analysis of performance of the autonomous vehicle.