Please add zabbix agent item keys: servers.active.discovery and, optionally, servers.passive.discovery

It wil be useful to build discovered items (and triggers) based on this discovery such as net.tcp.port[{#ZABBIX.SERVER},10051] - if port 10051 is not accessible from the monitored host, than some of active metrics can not be delivered to the zabbix server and monitoring administrator must be alerted some way about this problem...

Thank you!