Use when changes are repeatedly scattered across multiple files, ownership is unclear, there are no test boundaries, similar bugs/conflicts recur, or feature costs keep increasing.
Inspect for boundary leaks, ownership confusion, coupling hotspots, recurring problems, and incremental migration patterns. Cite concrete evidence and propose the smallest effective structural improvement. Do not recommend vague wholesale rewrites or implement automatically.
Conclude with evidence-backed hotspots, impact, and the smallest safe direction.