bread crumbs n. Debugging statements inserted into a program that emit output or log indicators of the program's state to a file so you can see where it dies or pin down the cause of surprising behavior.

bread crumbs n.

Debugging statements inserted into a
program that emit output or log indicators of the program's
state to a file so you can see where it dies or pin down the
cause of surprising behavior. The term is probably a reference to
the Hansel and Gretel story from the Brothers Grimm or the older
French folktale of Thumbelina; in several variants of these, a
character leaves a trail of bread crumbs so as not to get lost in
the woods.