The Silent Cost of Legacy Prompt Rules

As newer Claude models improve, legacy rules written for older versions accumulate unaudited, wasting context tokens and sometimes conflicting with updated defaults. Without systematic audits and clear retirement criteria, teams silently accumulate 'scaffolding debt' that degrades performance. The solution is straightforward: require every rule to carry WHY (the problem it addresses) and 'Retire when' (the observable condition for removal) tags, enabling teams to periodically audit and archive obsolete rules.