It's cool that it parses on the fly. But unless it parses correctly I don't see how it actually serves a purpose other than just looking cool.
> I heard you like phrase structure, so I put a phrase in your phrase so you can parse a phrase while you parse a phrase.
It misinterpreted "like" as 'in the manner of; akin to' ("I heard you as though [I were hearing] phrase structure"?), so I tried
> I heard you enjoy phrase structure, so I put a phrase in your phrase so you can parse a phrase while you parse a phrase.
That got parsed correctly.
Edit: well, it says "enjoy" is a base form rather than 3rd person singular, which is wrong in this context; it's an inflected form, like "I heard she enjoys phrase structure".
It also fails on "British left waffles on Falklands." While there are two syntactic parsers for that, one of them borders on the absurd and should be rejected. The problem is that to parse some sentences requires understanding of the words and phrases it reads, which in turn requires common sense.
Jeeves, dark forces are drawing us to Totleigh.
One does not even dare to try Marx Brothers quotes.