Our general-purpose assistant handles 100 million messages a week. Design how it responds when a user may be in crisis.

At a 0.05% base rate, a classifier that is right 99% of the time on safe messages still flags about twenty people who are fine for every one in danger. Build a ladder of responses that each fit their error rate.

Updated Nov 2026 · Original practice questions with worked answers and teaching rubrics. Our editorial policy explains the sources, review process and limits.