import type { Dtype } from './index.js';
export declare const HF_BASE = "https://huggingface.co";
export declare const HF_API = "https://huggingface.co/api";
export declare const ONNX_FILE_BY_DTYPE: Record<Dtype, string>;
/**
 * Fetch raw text or JSON from HF with retry+backoff on 5xx, no-retry on 4xx,
 * AbortController-based timeout. Returns null on permanent (404) or
 * exhausted-retry failures so callers can decide their fallback per-file.
 */
export declare function fetchWithRetry(url: string, opts: {
    timeoutMs: number;
    retries: number;
    fetcher: typeof fetch;
}): Promise<Response | null>;
export declare function fetchJson<T>(url: string, opts: {
    timeoutMs: number;
    retries: number;
    fetcher: typeof fetch;
}): Promise<T | null>;
export declare function fetchText(url: string, opts: {
    timeoutMs: number;
    retries: number;
    fetcher: typeof fetch;
}): Promise<string | null>;
export declare function sleep(ms: number): Promise<void>;