Definition
Plain language
Figuring out where in a codebase a bug actually lives before trying to fix it.
As stated in the literature
The task of identifying the file, function, or lines responsible for a software defect; reframed in SHERLOC as structured diagnosis (root cause and fix direction) rather than retrieval of a correct file path, and shown to consume roughly half of a coding agent's interaction budget.
Also called: localization
Why it matters: Most of the effort in fixing software goes into finding where the bug lives, so doing this well determines how fast and reliably problems get repaired.
For example, when a checkout page suddenly charges the wrong total, fault localization is the work of tracing the error down to the exact function doing the bad math.
Heard on the show
“And the categories that emerge are all over the map — localization tricks, perception prompts, grasping constraints, navigation recoveries, whole debugging workflows.”Episode 194 — How a Robot Builds a Debugging Notebook It Can Read, Edit, and Hand to Another Robot