Prior to the nice reorganization of 1354, http://drupal.org/node/1354/revisions/view/2415402/2546068
string was an optional type and assumed if a type was not specified
http://drupal.org/node/types
is linked from *data type indicator*:
in @param section
The @param tag is followed by an optional data type indicator, then the variable name of the parameter
and in @return section
The @return tag is followed by an optional data type indicator, and then a newline. The following paragraph is considered
maybe it just needs to be #types ?