export interface TunnelCredentials {
    access_token: string;
    refresh_token: string;
    expires_at: string;
    user: {
        id: string;
        email: string;
        tier: "free" | "paid";
    };
}
export declare class CredentialsService {
    private readonly logger;
    private static readonly CREDENTIALS_DIR;
    private static readonly CREDENTIALS_FILE;
    getCredentialsPath(): string;
    saveCredentials(credentials: TunnelCredentials): Promise<void>;
    loadCredentials(): Promise<TunnelCredentials | null>;
    clearCredentials(): Promise<void>;
    hasCredentials(): Promise<boolean>;
    isTokenExpired(credentials: TunnelCredentials): boolean;
    private ensureCredentialsDirectory;
    private validateCredentials;
}