MODULE Hello
CATEGORY Greetings
DESCRIPTION Prefixes "hello" to the input string
INPUT value;  string;  "world"; input string
OUTPUT greeting;  string; prefixed string

MODULE Add
CATEGORY User
DESCRIPTION Adds a number to a field
INPUT data; field; (none); field to add to
INPUT addend; scalar; 0; value to add to field
OUTPUT result; field; result of adding value to field

MODULE MakeX
CATEGORY Annotation 
DESCRIPTION draws an X 
INPUT input; field; (none); field to mark positions 
INPUT size; scalar; 1; size 
OUTPUT output;  field; field with positions marked 

