AW have 3 options or levels of detail
No email notification
A straightforward email notification to say we have a message in our inbox
Or a detailed message notification, What that means is when I get a message on aw it send me an email to tell me I have a message, in that email I can see the content of the aw message. It doesn't tell me who it's from.
So if it's a random 'Are you free now luv' and I'm not then I don't need to log on to know that, if it's a confirmation message I'm waiting for then I can log on and reply or if it's a number so I can message them then I don't need to log on I can take it off the email.
I have never as far as I know been able to reply to an aw message without logging on but someone like Ruth may be able to shed more light on that.