I plan on adding a dedicated 20A GFIC outlet above my kitchen
countertop, fed from a new 20A circuit breaker via 12-2 w/ground Romex
run through my attic and down inside the wall to the outlet. Two
questions:

1. Since it will be a dedicated circuit (only the one outlet on it)
does the electrical code require a junction box between the breaker
and the outlet?

2. Since the outlet will be the end of the line, is it necessary to
use wire caps and jumpers for the hot and neutral in the outlet box,
or can I simply run them straight to the outlet terminals? I've seen
the connections drawn both ways in reference books. They all show the
wire cap and jumper to a screw for the ground wire, but differ as to
the need for wire caps and jumpers for the other two wires.