The broadcast group definition 870 may be the list of default agents for a multi-agent entity. The agent client devices for the multi-agent entity correspond to the recipient devices 825. Where a user of a sender device 820 requests to communicate with a multi-agent entity, the sender device 820 may be provided with a list of default agent client devices for the default agents for the multi-agent entity. The list of default agent client devices for the multi-agent entity is then used as the broadcast group definition 870 to initiate encrypted group messaging with the default agents of the multi-agent entity. Each of the default agent client devices is similarly provided with a broadcast group definition comprising the other default agent client devices and the user client device.
The broadcast group definition 870 may additionally or alternatively include non-default agent client devices for non-default agents. Where a group message thread is created at initiation of messaging between the user and the multi-agent entity, the broadcast group definition 870 may include only the default agents. However, where a messaging initiation is with a single default agent, then a one-to-one message thread may be initially created, with the group message thread created in response to a non-default agent being assigned to the message thread. Once the non-default agent is assigned, the group message thread creation is initiated, and therefore includes the single default agent and one or more assigned non-default agents.