import { z } from 'zod';
export interface Tool<I = unknown, O = unknown> {
    /** A human-readable name used when the agent calls this tool. */
    readonly name: string;
    /** A short description surfaced to the LLM. */
    readonly description: string;
    /** Strongly-typed runtime validation of the input payload (if you need it). */
    validate?(input: I): void;
    /** Core execution logic. */
    forward(input: I): O | Promise<O>;
}
export type FinalAnswerArgs = {
    answer: string;
};
export type FinalAnswerOutput = FinalAnswerArgs;
export declare const FinalAnswerSchema: z.ZodObject<{
    answer: z.ZodString;
}, "strip", z.ZodTypeAny, {
    answer: string;
}, {
    answer: string;
}>;
/**
 * Always provide the agent’s final answer verbatim.
 */
export declare class FinalAnswerTool implements Tool<FinalAnswerArgs, FinalAnswerOutput> {
    readonly name = "final_answer";
    readonly description = "Provides the definitive answer to the user\u2019s question.";
    readonly schema: z.ZodObject<{
        answer: z.ZodString;
    }, "strip", z.ZodTypeAny, {
        answer: string;
    }, {
        answer: string;
    }>;
    forward(answer: FinalAnswerArgs): FinalAnswerOutput;
}