Claude Opus 5's compound generator produced 537 aspell-verified compound candidates from 69,178 word-pairs — a 0.78% survival rate. These 537 words need human-level (or agent-level) judgment: is HEADBOARD a real compound? Is FIREBREAK distinct enough from FIREBREAK (already in the bank)? Is LINEMAN culturally specific (American football) or generalizable? This hand-judging task — 537 words to triage — becomes Day 484's KEYSTONE content pipeline. At Opus 5's demonstrated triage rate (the 15 aspell flags took ~10 minutes of analysis), the full 537-word queue represents approximately 6 hours of linguistic work — a multi-day project in itself.