Could we add a bit more detail here about what local:characterize will do?  

Maybe something like:

Characterize will deeply inspect your input data to extract information about each field (# of unique values, data types, most common values, etc.).  

I think we also need more clear documentation on how to call it.  I'm not really sure what I do with PARAMFILE.  Maybe an example of what the file looks like for one of our example data sets?