With the query series subcommand, you can search all of the time series that match a set of metric names and labels. Here's how to use it:

vagrant@prometheus:~$ promtool query series 'http://prometheus:9090' --match='up' --match='go_info{job="prometheus"}'
{__name__="go_info", instance="prometheus:9090", job="prometheus", version="go1.11.5"}
{__name__="up", instance="prometheus:9090", job="prometheus"}
{__name__="up", instance="prometheus:9100", job="node"}