For the minute I think NLP systems are best off politely declining and staying home to troll Twitter
> kill the man
Which man?
> the one with the knife
I don't see that here.
> kill the man with the knife
You don't have the knife.
and so on...
What you refer to as preset is not strictly hand written, is it?
ambigious phrase or phrase token -> multiple possibilities the parser can handle -> multiple possibilities from the requester -> repeat until you've dialed down to a single possibility.
It's a big part of what the Machine Learning guys and the NLP guys are doing. But, as mentioned, there's very little context for a computer to work with...so everything is very specific. "google, find me movie theatres in the area" vs "i wonder what movies are around. do you have any ideas google?".
Most of that simplicity comes from the years of built up information and context you have. You can just say "want to go to the movies?" And be understood because that person knows of your dropped "do you" in "do you want", that "to the" very likely means "via motorized transport in either an independent or shared manner" and that "the movies" refers to a physical theatre, with a to-be determined showing.
NLP is a huge field and even the big names in the industry (Google, for example) are far off from anything resembling basic communication, beyond preset responses/dialogue trees.
The fact of the matter is, you're probably not getting anything resembling intelligent human communication, til we have AI. Something that can think for itself and create true context.