import * as speakeasy from 'speakeasy';
/**
 * Generates a secret key for TOTP.
 * @returns A generated secret key
 */
export declare function generateSecret(): speakeasy.GeneratedSecret;
/**
 * Generates a TOTP token based on the secret.
 * @param secret The user's TOTP secret
 * @returns The generated token as a string
 */
export declare function generateToken(secret: string): string;
/**
 * Verifies a TOTP token against the user's secret.
 * @param token The TOTP token to verify
 * @param secret The user's TOTP secret
 * @returns True if the token is valid, otherwise false
 */
export declare function verifyToken(token: string, secret: string): boolean;