import { z } from 'zod';
import { Storage } from '../../storage/storage.js';
/**
 * List subtasks, optionally filtered by task or project
 *
 * @param storage - Storage instance
 * @returns MCP tool handler for listing subtasks
 */
export declare function createListSubtasksTool(storage: Storage): {
    name: string;
    description: string;
    inputSchema: {
        taskId: z.ZodOptional<z.ZodString>;
        projectId: z.ZodOptional<z.ZodString>;
    };
    handler: ({ taskId, projectId }: {
        taskId?: string;
        projectId?: string;
    }) => Promise<{
        content: {
            type: "text";
            text: string;
        }[];
        isError: boolean;
    } | {
        content: {
            type: "text";
            text: string;
        }[];
        isError?: undefined;
    }>;
};