import type { RoutingInstructionState } from './routing-instructions.js';
export declare class StickySessionKeyMissingError extends Error {
    readonly key: string | undefined;
    constructor(key: string | undefined, message: string);
}
export declare function loadRoutingInstructionStateSync(key: string | undefined): RoutingInstructionState | null;
export declare function saveRoutingInstructionStateAsync(key: string | undefined, state: RoutingInstructionState | null): void;
export declare function saveRoutingInstructionStateSync(key: string | undefined, state: RoutingInstructionState | null): void;
