Being spoken to in local chat and in groups
An avatar can be given a nickname and told to listen. It then answers when somebody writes that nickname, and only then.
Why it needs a nickname
An instant message is addressed to your avatar: somebody chose to open a conversation with it. Local chat, a group and a conference are the opposite, and almost nothing said in them is meant for it. An avatar that answered every line would be unusable in a busy region.
So it answers to a name you give it. Somebody writes @ and that nickname, and that line is treated as though it had been sent as an instant message. Nothing else is answered.
It is listening even when it is silent
Everything it hears in a channel it is set to listen to is written down: who spoke, what they said, and when. That record is never trimmed.
It is what makes the answer sensible. Somebody can say three things about a hat and then write @shopbot how much is it, and the avatar knows what "it" was, because it was listening the whole time.
Master tab, Chat listening, is where you set the nickname and choose the channels: local chat, conferences, and any of the groups the avatar belongs to. All of them start switched off, and none of them can be switched on until the avatar has a nickname.
It answers where it was asked
A question asked in local chat is answered in local chat, and one asked in a group is answered in that group. Answering a public question privately would move a conversation somebody started in the open.
The answer begins with the name of whoever asked, because in a room where several people are talking an answer with nobody's name on it belongs to whoever reads it first.
The same rules as an instant message
Once a line has named the avatar it is treated exactly as an instant message from that person: Chat Grants decide whether they are answered at all, the authorized list still means what it means, banned residents are still ignored, and the direct commands still work. @bot follow me is the follow command.
IM relay applies too, with one exception. A line heard in local chat is not relayed to the Master while the Master is standing within twenty metres of the avatar, because that is how far local chat carries and they have already read it.