          ending handle of the specified characteristic.
          */
         
-        let start = characteristic.value + 1
-        
-        let end = end ?? start
+        let start = characteristic.handle.value + 1
+        
+        let end = start // FIXME:
         
         let operation = DescriptorDiscoveryOperation(start: start, end: end, completion: completion)
         

                
                let characteristic = Characteristic(uuid: declaration.uuid,
                                                    properties: declaration.properties,
                                                    declaration: handle,
                                                    value: declaration.valueHandle,
                                                    end: 0) // FIXME:
                
                operation.foundData.append(characteristic)
                

     ![Image](https://github.com/PureSwift/Bluetooth/raw/master/Assets/DiscoverAllCharacteristicDescriptors.png)
     */
    public func discoverDescriptors(for characteristic: Characteristic,
                                    completion: @escaping (GATTClientResponse<[Descriptor]>) -> ()) {
        
        /**
