For me to say, "I am called to be an intercessor," sounds highfalutin--a call that suggests vain glory, not a God call which, by its very nature is humbling and replete with mercy.
Occasionally I tell people, "I feel called to pray for people." But not often because the call is in the doing between God and me, not in any proclamation to the world. It is not a job, such as teaching . It is between God and me, and sometimes I feel called to let people know I am doing it. Fine, but that's not part of the call.