For example, I get value with key "myTag.some_total_time" by zabbix trapper. I want to see on graph average time of all values for last 5 minute. I know that there are "calculated items" and aggregate functions, but it can not be used with trapper values?
Calculated values can be used with trappers. To do this, you create a calculated element for the element you need.
Ex:
avg(//your_trap_item,5m)