import { Agent, ProxyAgent } from "undici";
/**
 * Proxy configuration type for separating search and URL reader proxies.
 */
export declare const ProxyType: {
    readonly SEARCH: "search";
    readonly URL_READER: "url_reader";
};
export type ProxyType = typeof ProxyType[keyof typeof ProxyType];
/**
 * Creates a proxy agent dispatcher for Node.js fetch API.
 *
 * Node.js fetch uses Undici under the hood, which requires a 'dispatcher' option
 * instead of 'agent'. This function creates a ProxyAgent compatible with fetch.
 *
 * Environment variables checked (in order, depending on URL protocol):
 * - For type 'search' and HTTPS URLs:
 *   SEARCH_HTTPS_PROXY, SEARCH_HTTP_PROXY, search_https_proxy, search_http_proxy,
 *   then HTTPS_PROXY, HTTP_PROXY, https_proxy, http_proxy
 * - For type 'search' and HTTP/unknown URLs:
 *   SEARCH_HTTP_PROXY, SEARCH_HTTPS_PROXY, search_http_proxy, search_https_proxy,
 *   then HTTP_PROXY, HTTPS_PROXY, http_proxy, https_proxy
 * - For type 'url_reader' and HTTPS URLs:
 *   URL_READER_HTTPS_PROXY, URL_READER_HTTP_PROXY, url_reader_https_proxy, url_reader_http_proxy,
 *   then HTTPS_PROXY, HTTP_PROXY, https_proxy, http_proxy
 * - For type 'url_reader' and HTTP/unknown URLs:
 *   URL_READER_HTTP_PROXY, URL_READER_HTTPS_PROXY, url_reader_http_proxy, url_reader_https_proxy,
 *   then HTTP_PROXY, HTTPS_PROXY, http_proxy, https_proxy
 * - For no specific type and HTTPS URLs:
 *   HTTPS_PROXY, HTTP_PROXY, https_proxy, http_proxy
 * - For no specific type and HTTP/unknown URLs:
 *   HTTP_PROXY, HTTPS_PROXY, http_proxy, https_proxy
 * - NO_PROXY / no_proxy: Comma-separated list of hosts to bypass proxy
 *
 * @param targetUrl - Optional target URL to check against NO_PROXY rules
 * @param type - Optional proxy type ('search' or 'url_reader') for separate proxy configs
 * @returns ProxyAgent dispatcher for fetch, or undefined if no proxy configured or bypassed
 */
export declare function createProxyAgent(targetUrl?: string, type?: ProxyType): ProxyAgent | undefined;
export declare function createDefaultAgent(): Agent | undefined;