Orchestrate many parallel subagents to run a large multi-file refactor, migration, or codemod sweep SAFELY and fast — partition by disjoint file ownership, fan out one write-agent per independent slice behind typecheck+build barriers, and synthesize their structured returns. Use when adopting a component library across routes, migrating design tokens / dark mode, running a rename or codemod sweep, modernizing per-route, or applying one rubric across a whole codebase — any breadth change that decomposes into independent file sets. Not for interdependent foundation work (shared config, a token layer, coupled modules) — do that inline.
