02 / LIKELY ERROR FAMILY
FOCUSED ERROR LINE
Terms the model recognized
Investigate in this order
BEFORE · SYNTHETIC EXAMPLE
AFTER · ONE POSSIBLE APPROACH
03 / MAKE IT STICK
FOR THE MOMENT YOUR CODE STOPS MAKING SENSE
Learn the bug.
Keep the lesson.
A small error explainer for students. Find a likely error family, understand the cause, then practice the idea behind the fix.
01 / YOUR ERRORPython + JavaScript
Try an example
Runs entirely in this browser. Your pasted text is not sent, saved or executed by TraceTutor.
{ ? }A fix is a line.
A fix is a line.
Understanding lasts longer.
Paste an error or pick an example. You’ll get an explanation, a tiny before-and-after, and one practice question.
10 error familiesClassical text classifier