guardrails

Generation at scale where the model writes copy nobody reviews before it reaches millions of phones. The design is about templates, guardrails and cost, more than about the model.

Guardrails are often described as a box in a diagram. The interviewer wants specific checks, where each runs, what it costs in latency, and what happens when one fires.

A classic experiment-design question with AI-specific traps: novelty that fades, quality that differs by segment, and a cost line that classic A/B tests never had.

Usage counts are the trap. The answer that scores connects quality, behaviour, cost and risk to one business outcome, and says what evidence would change the primary metric.

Progressive constraints test whether you can adapt under pressure without breaking what works. Principal-level candidates handle each constraint with the right mechanism, verify each change, and explain trade-offs.