export class MCPAuthProxyError extends Error { constructor(message: string, public code: string) { super(message) this.name = 'MCPAuthProxyError' } } export class InvalidCredentialsError extends MCPAuthProxyError { constructor() { super('Invalid or expired credentials', 'INVALID_CREDENTIALS') } } export class OAuthError extends MCPAuthProxyError { constructor(message: string) { super(message, 'OAUTH_ERROR') } } export class ProxyError extends MCPAuthProxyError { constructor(message: string) { super(message, 'PROXY_ERROR') } } export class TransportError extends MCPAuthProxyError { constructor(message: string) { super(message, 'TRANSPORT_ERROR') } }