ANTI-SLOP — The Agent Design Playbook: Ten tells of AI-built UI + a pass/fail browser QA gae

We had an AI build two fictional storefronts in one afternoon — a Warsaw watch manufacture and a tiny type foundry. The agent's own code review passed its work. Our gate did not: run against the live page at 3 breakpoints, it caught 4 bugs the model had already signed off on (a hero shipped on a screen that needed a spec table; a buy bar whose price floated off-screen at 375px). The playbook is the doctrine that came out of it: the ten structural tells of AI-built UI, the ~1KB pre-prompt that kills the visual ones before code exists, and the pass/fail acceptance gate that runs in a real browser and ships its failure screenshots as receipts. 12 pages, real teardowns with screenshots, zero income promises. The 2-page extract is free — link above.