think-twice

Forces Claude to pause before picking an implementation approach and ask: "Is there a cleverer, cheaper way?" Triggers when the request involves generating data or fixtures (lists, datasets, sample records), implementing a problem that is likely already solved by a stdlib function, package, or public API (validation, parsing, lookups, auth, date/currency/geo data), or any implementation expected to exceed ~20 lines. Does NOT trigger when the user has explicitly chosen the approach or library, when the task is under ~10 lines, when fixing a bug in existing code, or for infra/terraform/k8s and DB queries. Run the checklist before writing code, stop at the first question that reveals a cheaper path, and take that path.