Are you a developer wishing you could insert Siri-like capabilities into your app? Wit is in the alpha phase but worth a close look. In the graphic below, and if you go to their website, y0u see how it translates language into meaning. Every example parses an intent. Examples are weather forecast (from the graphic), restaurant booking, get (something), heating control. There are an infinite number of intentions--because you can define them. Then it figures out subsequent pieces (the when and place in the example below. The Wit API returns Json and authenticates with OAuth2.
An interesting feature in the API documentation is the discussion of its JSON responses, including intent (that it has guessed at based on ones set in your console), variables, and a confidence rating that is either 0 or 1 based on the confidence it has in its outcome.
To get a better idea of how you "teach" wit to do the tricks relevant to your app, below is a shot of the console, which you can find in a intro documentation page. It shows two sentences to set up. Wit defines "intent" as "something the user wants to do," such as: ask about weather, sports scores, reminders, turn on lights, among an infinite set.
Wit also has an interesting set of known use cases, among them: personal assistants like Siri, using Wit on top of Android's voice recognition for natural commands, and IM-based information.