export interface ResponseCacheEntry {
    url: string;
    etag?: string;
    lastModified?: string;
    cacheControl?: string;
    body: string;
    contentType: string;
    statusCode: number;
    cachedAt: number;
    hitCount: number;
}
export declare class ResponseCache {
    private readonly dir;
    private totalHits;
    private totalRequests;
    constructor(cacheDir: string);
    private key;
    private path;
    get(url: string): ResponseCacheEntry | null;
    private read;
    isFresh(url: string): boolean;
    staleIfError(url: string): boolean;
    set(url: string, entry: Omit<ResponseCacheEntry, 'cachedAt' | 'hitCount'>): void;
    getValidationHeaders(url: string): {
        'If-None-Match'?: string;
        'If-Modified-Since'?: string;
    };
    markHit(url: string): void;
    invalidate(url: string): void;
    clear(): void;
    stats(): {
        entries: number;
        totalSizeBytes: number;
        hitRate: number;
        totalHits: number;
    };
    prune(maxAgeMs: number): number;
}