Controllers can communicate with accessories using various paths, such as a wireless communication path. A controller can maintain reachability information for each accessory indicating the path(s) via which the accessory is currently reachable. Maintaining the reachability information can include scanning to detect broadcasts from the accessories and updating the reachability information based on the results of scanning. Scanning parameters such as scan interval and scan duration can be selected dynamically based on the current operating context of the controller (e.g., where the controller is located, what processes are active on the controller, what other devices have been detected within communication range of the controller).