/**
 * Validates raw path string and extracts clean segments.
 * Throws NexaError('invalid-argument') on any validation failure.
 */
export declare function validatePathSegments(path: string): string[];
/**
 * Validates that a path points to a valid collection (odd number of segments).
 */
export declare function validateCollectionPath(path: string): string;
/**
 * Validates that a path points to a valid document (even number of segments).
 */
export declare function validateDocumentPath(path: string): string;
/**
 * Generates a 20-character alphanumeric auto-ID matching Firestore specifications.
 */
export declare function generateAutoId(): string;