Answer prose round 1: the custom-CLI test advice says why an indexed module needs each path rendered, the help ruling says the help points to --list and who ruled, ErrNoColumns's doc says what it matches, and the filed items read in one pass

internal/datafiles/datafiles.go

@@ -104,7 +104,7 @@ func (s Source) check() error {
 	return nil
 }
 
-// noDirectory is a data path naming nothing, which errors.Is still matches as fs.ErrNotExist.
+// noDirectory is a data path naming nothing.
 type noDirectory string
 
 func (d noDirectory) Error() string { return "data path " + string(d) + ": no such directory" }

internal/jsonvalue/jsonvalue.go

@@ -25,7 +25,7 @@ func Decode(b []byte) (Value, error) {
 	return Value{v}, err
 }
 
-// located prefixes a syntax error with the line and column of the byte it stopped at.
+// located prefixes a syntax error with the line and column where decoding stopped.
 func located(b []byte, err error) error {
 	var syntax *json.SyntaxError
 	if !errors.As(err, &syntax) {