            uint256 verbId = _currentVerbId++;
    function getArtPieceById(uint256 verbId) public view returns (ICultureIndex.ArtPiece memory) {
-        require(verbId <= _currentVerbId, "Invalid piece ID");
+        require(verbId < _currentVerbId, "Invalid piece ID");
        return artPieces[verbId];
    }
