I have previously posted what I know about Project Oxford and Microsoft LUIS on the Chatbots.org forum at, including a personal explanation provided by of Microsoft Research:
LUIS lets you build an LU model specific to your domain. That LU models takes text (the “question”) as input and produces JSON as output. The JSON contains 2 things: the “intent” of the whole question, and 0 or more entities, which are substrings. The JSON does not contain the “answer” to read back—rather it is classifying the input into categories that you specify. Your app can then use the “category” of the input (rather than the raw input text) to decide what to do.
There is some more recent information available on the blog at:
- (Oct 2015)