List groups

The group conversations your lines belong to.

A group is a conversation that isn’t a phone number, so Dial gives it an ID of its own; you address it with groupId on Send a message and filter for it on List messages. Groups exist on WhatsApp lines and iMessage numbers, and each one reports which of the two it is on in channel — the channel’s own rules then apply to anything sent into it.

name may be null, which is not an error. Participants rename groups, so Dial stores no copy of the subject — it is read live from the line that holds the conversation. A line that can’t answer in time yields name: null for its groups rather than failing the request, so one unreachable line never hides another line’s groups.

Your line must already be a member: Dial can send into a group your number was added to, but cannot create one, join one, or accept an invite link.

There is no join event — a group your line was just added to shows up as a new entry here.