Vercel ran more than 200 agent runs to build design.md, a new public prompt file designed to help agents create web pages that look and feel like Vercel. ^[1] Researchers introduced ReproRepo, a scalable framework for reproducibility evaluation that leverages human-raised GitHub issues as naturally occurring supervision on realistic reproduction blockers. ^[2] Critical page-level leakage remained at 0.968 despite the improvements in localization metrics. ^[3] Researchers introduced LeakageBench, a challenge set of 500 document images containing 11,954 GDPR-aligned PII annotations spanning direct identifiers, linkage keys, and contextual re-identification surfaces. ^[4] The authors present ToolGate, a system that treats every AI-generated benchmark item as a proposal subject to three validation gates. ^[5] In a test comparing Codex with GPT-5.5, Vercel's deterministic checks counted 39 instances of known failure modes with design.md loaded, compared to 91 without it. ^[6] The experiment demonstrated a 57% reduction in known failure modes when using the design.md file compared to unguided generation. ^[7] Vercel acknowledged that every one of the six pages tested had a failure large enough to prevent shipping, even with the guidance file. ^[8]