Event:
#chat tell
Sub:
Sub Event_Chat(ChatType,Sender,ChatText)
/if (${ChatText.Equal[invite]}) {
/invite ${Sender}
}
/return
Or, if you have a pre-set group you're inviting:
Sub Event_Chat(ChatType,Sender,ChatText)
/if (${ChatText.Equal[invite]}) {
/invite name...