Variable: AppCircuitState

const AppCircuitState: z.ZodEnum<{
  closed: "closed";
  half_open: "half_open";
  open: "open";
}>;

An install's circuit breaker, one per install shared by every worker (app-circuits.ts): open after the vendor's outages (timeouts and errors the app calls retryable) with no success between them, when calls fail at once without reaching the runner; half_open while a trial call is let through.