See options.mk, in the case without options nagios-nrpe-args:
# Upstream's configure enables command args when given
# "--disable-command-args", so (departing from pkgsrc norms) don't
# give the --disable option.
PKGREVISION++; the previous version enabled command args when it
should not have.
This option passes -enable-command-args to configure, and is intended
to allow the use of arguments to nrpe. From Brian A. Seklecki via PR
pkg/43920.
However, configure.in seems broken, and it seems command args are
always enabled.
This Nagios addon is designed to provide a way for executing plugins on
a remote host. The check_nrpe plugin runs on the Nagios host and is used
to send plugin execution requests to the nrpe agent on the remote
host. The nrpe agent will then run an appropriate plugins on the
remote host and return the plugin output and return code to the
check_nrpe plugin on the Nagios host.