How to debug ORA-01775: looping chain of synonyms?

I'm familiar with the issue behind ORA-01775: looping chain of synonyms, but is there any trick to debugging it, or do I just have to "create or replace" my way out of it?

Is there a way to query the schema or whatever to find out what the current definition of a public synonym is?

Even more awesome would be a graphical tool, but at this point, anything would be helpful.

As it turns out, the problem wasn't actually a looping chain of synonyms, but the fact that the synonym was pointing to a view that did not exist.

Oracle apparently errors out as a looping chain in this condition.

If you are using TOAD, go to View>Toad Options>Oracle>General and remove TOAD_PLAN_TABLE from EXPLAIN PLAN section and put PLAN_TABLE