S1025: the argument is already a string, there's no need to use fmt.Sprintf (gosimple)

SA4005: ineffective assignment to field writer.err (staticcheck)

SA1019: strings.Title has been deprecated since Go 1.18 and an alternative has been available since Go 1.0: The rule Title uses for word boundaries does not handle Unicode punctuation properly. Use golang.org/x/text/cases instead. (staticcheck)