import { type Dispatcher } from 'undici';
/** Default deadline kept below the Harness web-search tool deadline. */
export declare const DEFAULT_REQUEST_TIMEOUT_MS = 25000;
/** Maximum bytes accepted from any external JSON response. */
export declare const MAX_RESPONSE_BYTES: number;
/** Per-request transport controls shared by every backend. */
export interface FetchJsonOptions {
    readonly signal?: AbortSignal;
    readonly timeoutMs?: number;
}
/** Fetch and parse an untrusted JSON response with shared web error codes. */
export declare function fetchJson(provider: string, url: string | URL, init: RequestInit, options?: FetchJsonOptions): Promise<unknown>;
/**
 * Resolve the plugin-only outbound proxy. This deliberately does not install a
 * global dispatcher, so model providers and other DSH plugins keep their own
 * network policy. Private and explicitly excluded hosts stay direct for local
 * SearXNG deployments.
 */
export declare function dispatcherFor(input: string | URL): Dispatcher | undefined;
/** Resolve a non-empty credential for one API request without caching it. */
export declare function resolveCredential(provider: string, reference: string, resolve: () => Promise<string | undefined>, signal?: AbortSignal): Promise<string>;
/** True when a parsed JSON value is a plain record. */
export declare function isRecord(value: unknown): value is Record<string, unknown>;
/** Validate one absolute HTTP(S) URL returned by an external provider. */
export declare function requiredHttpUrl(value: unknown, path: string): string;
/** Return a trimmed optional string or omit blank values. */
export declare function optionalString(value: unknown, path: string): string | undefined;
/** Cap a provider request to its supported result-count range. */
export declare function resultLimit(value: number | undefined, maximum: number, fallback: number): number;
/** Convert a validated provider response and normalize all field errors. */
export declare function decodeResponse<T>(provider: string, value: unknown, decode: (input: unknown) => T): T;
/** Remove MediaWiki result markup and decode its common entities. */
export declare function plainText(value: string): string;