I use the Workflow History List for debugging and the option of turning on debugging for flows that are in production.  I would however like a workflow that purges the records in this list based by the workflow Name.  I have created a workflow and a Delete HTTP request, but can't get it to work.  I can't find any documentation on how to do this.  What I have is

     [%Workflow Context:Current Site URL%]/_api/lists/GetByTitle('Workflow 
History')?$select=Id as my String in my Call

I get the following response code:

     response=PreconditionFailed
============================================
I think I'm getting it, but still don't know how to put the pieces together.  My understanding now is that I create a HTTP Rest to select the IDs of each record.
Then I have to follow it with two more HTTP requests one to get the item and the other to delete the item.  It is these later two that I don't know how to do.  Am I on the right track?