There is a Jazz lyric about an "errand girl for rythm." "Errand boy" would seem the parallel case. "Errand person," though, seems far too PC and stilted.
A mail carrier
If you are sent on an errand or run an errand for someone you are doing a small job for them that takes you away from the home or where you would normally be. [A short trip taken to perform a specified task, usually for another]. Delivering a message to your mothers friend down the road or going out to collect the groceries would be 'running an errand'.
Well an "errand" is a job that someone asked the person to do.
I had to run an errand.
The Fool's Errand was created in 1987.
The Fool's Errand happened in 1987.
Yes, errand is singular; the plural is 'errands'.
The meaning of errand in Tagalog is "padalang mensahe o kahilingan."
The duration of The Errand of Angels is 1.52 hours.
The duration of The Errand Boy is 1.53 hours.
The Errand Boy was created on 1961-11-28.
The Errand of Angels was created on 2008-09-05.