I wouldn’t call it an error per se, but it’s definitely unidiomatic. Native speakers will consistently produce big brown spider far more often than ?brown big spider. Some languages enforce this more strictly than others, and in some the words can be deliberately moved out of the usual order for emphasis. (E.g. in such a language, a phrase equivalent to “brown big spider” would roughly mean “big brown spider”.)
I wouldn’t call it an error per se, but it’s definitely unidiomatic. Native speakers will consistently produce big brown spider far more often than ?brown big spider. Some languages enforce this more strictly than others, and in some the words can be deliberately moved out of the usual order for emphasis. (E.g. in such a language, a phrase equivalent to “brown big spider” would roughly mean “big brown spider”.)