What problem does it solve? Historical fiction, period drama, and documentary prose lose credibility when a single anachronistic word, object, or social assumption slips through. This Skill provides a structured four-layer audit that catches linguistic, technological, legal, and historiographical errors before publication. ## Core Features & Use Cases - Linguistic Verification: Checks idioms and vocabulary against OED first-usage dates to catch terms like "brainwash" (1950) appearing in earlier settings. - Material Culture Audit: Validates lighting, transit, textiles, fasteners, and medical practices against the exact target year. - Social & Legal Realism Check: Verifies property rights, class structures, and institutional constraints such as coverture for married women. - Use Case: A novelist drafting a story set in 1845 London runs the audit and receives a HISTORICAL-AUDIT.md report listing each anachronism, why it is wrong, and a period-accurate replacement. ## Quick Start Audit this manuscript chapter set in Victorian London for historical anachronisms and produce a correction report.