It's difficult to tell whether a metadata wrangler integration is working. If it's not working, it's difficult to tell whether the problem is on the circ manager side or the metadata side.

A self-test for a metadata wrangler integration would add some visibility here. Off the top of my head, these things would be useful to know:

• The metadata identifiers for each collection registered with the metadata wrangler
• For each such colleciton:
  • The number of identifiers registerer
  • An example of metadata from registered identifiers, taken from the metadata wrangler's update feed from that collection
  • For each handler on the metadata side:
    • How many identifiers have been processed by that handler (this seems tough to put into OPDS form).