How should I test my multiplayer addon?

I’m making an addon that uses custom ulx commands for a party system.
There are commands to create a party, join a party, etc.
I’m not sure how I can test this.
I can create a party, but then I can’t have anyone join it without using another computer and another steam account.
I tried spawning in a bot and then using “ulx cexec ‘Bot01’ ‘party join ThaBullfrog’”, but It seems like bots can’t execute console commands.
I don’t know what to do.

Thanks, -multirun works, but you need to set up a shortcut for it. I initially used Steam’s “Set Launch Options…” button to put in the parameter, but that didn’t work.

EDIT: Wait, I’m getting this error: “S3: Duplicate client connection: UserID: 4 SteamID XXXXXXX” even though sv_lan is set to 1. I double checked. I know sv_lan is 1, and I’m still getting this error.

Servers comandline:

-insecure didn’t fix it

sv_lan 1 must be set before the server starts.

Thanks, that was the issue. I had it set in server.cfg, but if you add this command line parameter to the server it works: +sv_lan 1

on a server

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