Grafana cloudwatch alert

I want to set alert on cloudwatch elb dashboartd. The cloudwatch datasource is working and i was able to install cloudwatch elb dashboard.
under alerting i was able to set alert rule say when a ELB mertic TargetResponseTime, in the summary field, i want to display the loadbalancer (dimanesion) and taretgroup name, but i am able to find what that variable is? Is there a list of variables that i can use with in summary/description?