Starting with Zabbix version 3.0, one can encrypt communication between zabbix server/proxies and agents/cmd tools using a PSK. This requires a unique identity string per host.
When using different PSK/Identities, it would make management more easy, if there would be a central place to mange the identies and have a sort of dropdown or similar to select those unassigned identities within the host configuration.
Also, currently one can setup the same identy with different PSKs across multiple hosts, which is a misconfiguration. Maybe there could be a check to warn the user if an identity already exists, but with a different PSK. (or maybe an internal item that checks for integrity)
Currently, the only way to get an overview for used identities is to query the database:
select h.host, h.tls_accept, h.tls_psk, h.tls_psk_identity from hosts as h where h.tls_psk_identity != ''