export declare class McpToolError extends Error {
    readonly cause?: unknown | undefined;
    constructor(message: string, cause?: unknown | undefined);
}
export declare function toActionableError(error: unknown): string;
export declare function formatFatalError(error: unknown): string;
export declare function toolError(message: string): {
    content: {
        type: "text";
        text: string;
    }[];
    isError: true;
};
export declare function toolSuccessMarkdown(text: string): {
    content: {
        type: "text";
        text: string;
    }[];
};
export declare function toolSuccess(text: string, structuredContent?: Record<string, unknown>): {
    content: Array<{
        type: "text";
        text: string;
    }>;
    structuredContent?: Record<string, unknown>;
};