This is a plug&play command that allows players to add new party members from anywhere, through a player list gump.
Just drop this script somewhere in your Scripts folder.
[AddToParty - Opens a gump with a list of players online available to be invite.
[AddToParty <name> - Sends the invite directly the specified player.
You can configure this system at the top of the script.
bool Enabled = true; // Is this command enabled? bool OnlyLeadersCanAdd = true; // New party members can only be added by the party leader?
Gump seen by the invited player