/**
 * C15TError - Custom error class for typed error handling
 *
 * @example
 * ```typescript
 * import { C15TError } from '@c15t/node-sdk';
 *
 * try {
 *   const subject = (await client.getSubject('sub_123')).unwrap();
 * } catch (error) {
 *   if (error instanceof C15TError) {
 *     console.log(error.status); // 404
 *     console.log(error.code);   // 'NOT_FOUND'
 *     console.log(error.details);
 *   }
 * }
 * ```
 */
export declare class C15TError extends Error {
    /**
     * HTTP status code of the error response
     */
    readonly status: number;
    /**
     * Error code for programmatic error identification
     */
    readonly code?: string;
    /**
     * Additional error details
     */
    readonly details?: Record<string, unknown> | null;
    /**
     * Original cause of the error (if any)
     */
    readonly cause?: unknown;
    constructor(options: {
        message: string;
        status: number;
        code?: string;
        details?: Record<string, unknown> | null;
        cause?: unknown;
    });
    /**
     * Check if the error is a specific HTTP status code
     */
    isStatus(status: number): boolean;
    /**
     * Check if the error is a not found error (404)
     */
    isNotFound(): boolean;
    /**
     * Check if the error is a validation error (400)
     */
    isValidationError(): boolean;
    /**
     * Check if the error is an authentication error (401)
     */
    isUnauthorized(): boolean;
    /**
     * Check if the error is a forbidden error (403)
     */
    isForbidden(): boolean;
    /**
     * Check if the error is a server error (5xx)
     */
    isServerError(): boolean;
    /**
     * Check if the error is a network error
     */
    isNetworkError(): boolean;
    /**
     * Convert error to a plain object for serialization
     */
    toJSON(): {
        name: string;
        message: string;
        status: number;
        code?: string;
        details?: Record<string, unknown> | null;
    };
}
/**
 * Type guard to check if an error is a C15TError
 */
export declare function isC15TError(error: unknown): error is C15TError;