/**
 * Circuit breaker — auto-disable models that fail repeatedly.
 * States: closed (normal), open (blocked), half-open (allow one probe).
 */
export type CircuitState = 'closed' | 'open' | 'half-open';
export interface CircuitStatus {
    state: CircuitState;
    failures: number;
    lastFailure: number;
    openedAt: number;
}
export declare function configureCircuitBreaker(opts: {
    threshold?: number;
    cooldownMs?: number;
}): void;
export declare function recordSuccess(model: string): void;
export declare function recordFailure(model: string): void;
export declare function isCircuitOpen(model: string): boolean;
export declare function getCircuitState(model: string): CircuitStatus;
export declare function getAllCircuitStates(): Record<string, CircuitStatus>;
export declare function resetCircuitBreaker(): void;
