How do you build content moderation / toxicity classification, and what makes it hard?

Toxicity detection looks like vanilla text classification and is anything but: context flips labels, adversaries evolve weekly, and naive models flag dialects as hate. The signal is naming those failure modes and designing the human-in-the-loop system around them.

Updated Aug 2026 · Grounded in real Applied AI Engineer interview loops and written to a senior-engineer editorial bar.