anchor.diff:  _https://example.com/johndoe/0f0f0f0f0f...0f_
   
   ==== +HTTP GET+
  -Returns properties for the device, optionally filtered.
  -
  -===== Query parameters
  -*filter*=[string[,string ...]]::
  -  (_optional_)
  -  When set, filter the properties returned by the names in the filter string.
  +Returns properties for the device.
   
   ===== Server Response
   `DeviceDescriptor`
   
   ==== +HTTP POST+
  -Sets properties for the device, then returns the devices new properties,
  -optionally filtered.
  -
  -===== Query parameters
  -*filter*=[string[,string ...]]::
  -  (_optional_)
  -  When set, filter the properties returned by the names in the filter string.
  +Sets properties for the device, then returns the devices (updated) properties.
   
   ===== Client Request
   `Dictionary`
  
positive.code: `RegisterRequestData`
    
  ==== +HTTP POST+
  
  ===== Query parameters
  *filter*=[string[,string ...]]::
    (_optional_)
    When set, filter the properties returned by the names in the filter string.
  
  Completes the registration, storing a new device associated with the user.
  
  ===== Client request body
  
negative.code: _https://example.com/johndoe_
  
  ==== +HTTP GET+
  Returns a list of device handles, with their properties.
  
  ===== Server response
  `DeviceDescriptor[]`
  