Starting in a few weeks, we will require that all API calls include a valid API key. See the original post that describes how to insert a key in your request. These keys have proven useful on a number of occasions where we have reached out to developers whose apps are causing issues on our servers. Your cooperation has been appreciated. If you are already adding a key, there is no action for you to take. If not, please get your key and start adding it to all requests as soon as possible.