check:checker/2

checker(:Goal, +Message:text) is nondet[multifile, library(check)]

Register code validation routines. Each clause defines a Goal which performs a consistency check executed by check/0. Message is a short description of the check. For example, assuming the my_checks module defines a predicate list_format_mistakes/0:

:- multifile check:checker/2.
check:checker(my_checks:list_format_mistakes,
              "errors with format/2 arguments").

The predicate is dynamic, so you can disable checks with retract/1. For example, to stop reporting redefined predicates:

retract(check:checker(list_redefined,_)).