First, let’s take a look at the response that we get from Tumblr, so you get a better idea of what data is made available to us.
Every Tumblr blog comes with a public JSON API. You simply have to add
/api/read/json after the end of your blog URL to get a JSON object with your recent posts. This is a breath of fresh air compared to the direction Facebook and Twitter have taken their APIs, which require access tokens and registrations for even the simplest of use cases.