Recently I was working on a task where I was attempting to connect to a third party API (from a Rails app using the HTTParty gem). The API had a fairly complicated authorization header that needed to be built, by concatenating the body of the request itself along with various authorization headers, then being hashed, and then being base64 encoded and escaped. If the header was improperly formed, all I saw was a 403 Forbidden response - not particularly helpful for debugging.