/**
 * MCP Error Codes
 *
 * Machine-readable error codes for MCP tool responses.
 * Part of the Lex 1.0.0 contract - orchestrators can branch on these codes.
 *
 * @example
 * ```typescript
 * if (response.error?.code === MCPErrorCode.INVALID_MODULE_ID) {
 *   // Handle module ID validation failure
 * }
 * ```
 */
/**
 * Error codes for MCP tool operations
 *
 * Naming convention: CATEGORY_SPECIFIC_ERROR
 * - VALIDATION_* : Input validation errors
 * - STORAGE_* : Database/storage errors
 * - POLICY_* : Policy-related errors
 * - INTERNAL_* : Unexpected internal errors
 */
export declare enum MCPErrorCode {
    /** Required field is missing */
    VALIDATION_REQUIRED_FIELD = "VALIDATION_REQUIRED_FIELD",
    /** Field has invalid format or type */
    VALIDATION_INVALID_FORMAT = "VALIDATION_INVALID_FORMAT",
    /** Module ID does not match any module in policy */
    VALIDATION_INVALID_MODULE_ID = "VALIDATION_INVALID_MODULE_ID",
    /** module_scope array is empty */
    VALIDATION_EMPTY_MODULE_SCOPE = "VALIDATION_EMPTY_MODULE_SCOPE",
    /** status_snapshot structure is invalid */
    VALIDATION_INVALID_STATUS = "VALIDATION_INVALID_STATUS",
    /** Image data is malformed or unsupported */
    VALIDATION_INVALID_IMAGE = "VALIDATION_INVALID_IMAGE",
    /** Path provided does not exist or is inaccessible */
    VALIDATION_INVALID_PATH = "VALIDATION_INVALID_PATH",
    /** Failed to save frame to database */
    STORAGE_WRITE_FAILED = "STORAGE_WRITE_FAILED",
    /** Failed to read from database */
    STORAGE_READ_FAILED = "STORAGE_READ_FAILED",
    /** Failed to delete from database */
    STORAGE_DELETE_FAILED = "STORAGE_DELETE_FAILED",
    /** Failed to store image attachment */
    STORAGE_IMAGE_FAILED = "STORAGE_IMAGE_FAILED",
    /** Frame with given ID was not found */
    STORAGE_FRAME_NOT_FOUND = "STORAGE_FRAME_NOT_FOUND",
    /** Policy file not found or unreadable */
    POLICY_NOT_FOUND = "POLICY_NOT_FOUND",
    /** Policy file has invalid structure */
    POLICY_INVALID = "POLICY_INVALID",
    /** Unknown tool name requested */
    INTERNAL_UNKNOWN_TOOL = "INTERNAL_UNKNOWN_TOOL",
    /** Unknown MCP method requested */
    INTERNAL_UNKNOWN_METHOD = "INTERNAL_UNKNOWN_METHOD",
    /** Unexpected internal error */
    INTERNAL_ERROR = "INTERNAL_ERROR"
}
/**
 * Error code metadata for agent introspection
 */
export interface MCPErrorCodeMetadata {
    /** Error category (validation, storage, policy, internal) */
    category: "validation" | "storage" | "policy" | "internal";
    /** Whether the error is potentially retryable (e.g., transient storage issues) */
    retryable: boolean;
}
/**
 * Metadata map for all error codes
 * Agents can use this to understand error categories and retry behavior
 */
export declare const MCP_ERROR_METADATA: Record<MCPErrorCode, MCPErrorCodeMetadata>;
/**
 * MCP Error with structured code and metadata
 */
export declare class MCPError extends Error {
    readonly code: MCPErrorCode;
    readonly metadata?: Record<string, unknown>;
    constructor(code: MCPErrorCode, message: string, metadata?: Record<string, unknown>);
    /**
     * Convert to MCP response error format
     */
    toResponse(): {
        error: {
            code: string;
            message: string;
            metadata?: Record<string, unknown>;
        };
    };
}
/**
 * Helper to create validation errors with suggestions
 */
export declare function createValidationError(code: MCPErrorCode, message: string, suggestions?: string[]): MCPError;
/**
 * Helper to create module ID validation error with available modules
 */
export declare function createModuleIdError(invalidIds: string[], suggestions: string[], availableModules: string[]): MCPError;