anchor.diff:  _validity_ in those tools, you will need to declare the catalog schema
   location like so:
   
  +[source,xml]
   -------------------------------------------------------------------------------------------------
   <catalog name="Validation" xmlns="http://www.unidata.ucar.edu/namespaces/thredds/InvCatalog/v1.0"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  
positive.code: should form a globally-unique identifier for a dataset. In the TDS, it
  is especially important to add the `ID` attribute to your datasets.
  
  -----------------------------------------------------------------------------------------
  <service name="odap" serviceType="OpenDAP" base="/thredds/dodsC/"/>
  
  
negative.code: services. Elements such as `summary`, `rights`, and `publisher` are
  needed in order to create valid entries for these services.
  
  [source,xml]
  ------------------------------------------------------------------------------------------------------------------------------------------------------------
  <dataset name="SAGE III Ozone Loss Experiment" ID="Sage III" harvest="true">
    <contributor role="data manager">John Smith</contributor>
  