import type { IncomingHttpHeaders, IncomingMessage } from "node:http";
export declare class RateLimitError extends Error {
    readonly status = 429;
    constructor(message?: string);
}
export declare function assertRateLimit(key: string, options: {
    blockMs: number;
    limit: number;
    windowMs: number;
    message?: string;
}): void;
export declare function recordRateLimitFailure(key: string, options: {
    blockMs: number;
    limit: number;
    windowMs: number;
}): void;
export declare function clearRateLimit(key: string): void;
export declare function forceRateLimitSweepForTests(now?: number): void;
export declare function rateLimitBucketCountForTests(): number;
export declare function resetRateLimitStateForTests(): void;
export declare function requestRateLimitKey(request: IncomingMessage, scope: string, subject?: string): string;
export declare function requestClientAddress(headers: IncomingHttpHeaders, remoteAddress: string | undefined): string;