import { Tool } from "@langchain/core/tools";
/**
 * Interface for the parameters required to instantiate a BraveSearch
 * instance.
 */
export interface BraveSearchParams {
    apiKey?: string;
}
/**
 * Class for interacting with the Brave Search engine. It extends the Tool
 * class and requires an API key to function. The API key can be passed in
 * during instantiation or set as an environment variable named
 * 'BRAVE_SEARCH_API_KEY'.
 */
export declare class BraveSearch extends Tool {
    static lc_name(): string;
    name: string;
    description: string;
    apiKey: string;
    constructor(fields?: BraveSearchParams);
    /** @ignore */
    _call(input: string): Promise<string>;
}