The join can be used to make Corrade join a group.

llInstantMessage(CORRADE,
    wasKeyValueEncode(
        [
            "command", "join",
            "group", wasURLEscape(GROUP),
            "password", wasURLEscape(PASSWORD)
        ]
    )
);

• The function checks whether joining a group requires a member ship fee, and if that is the case, Corrade checks for economy permission. If the economy permission is granted as well, then Corrade checks whether the current balance is sufficient, pays the fee and joins the group.