Custom Attributes

Does anyone have an example of the use of custom attributes in a DeviceHandler. I tried adding an attribute:
attribute “debugme”, “string” into the metadata which seems ok. But then later when I try to access this as:
device.debugme, I get an exception. Am I just fundamentally misunderstanding how / what an attribute is?
I was able to add it to “state” without an issue but that seems incorrect to me.

Custom attributes are data bits the device provides. Examples: temperature, humidity. You would add custom attributes for any data bits that aren’t handled by any capabilities you may be using.

To access the attribute, you can use device.currentValue(‘attributeName’).

Thank you. Is there an example of setting the value of the attribute programmatically?

I’ve just done it by sending an event:

def newValue = "test"
sendEvent(name: “attributeName”, value: newValue)

I’m not sure if there is another way.