I hate myself for saying it, because of all of the buzz/hype, but LLMs can assist here.

You get better intent assessment than with NLP/ regex/whatever.

Plus HN is entirely in English, so you never have to worry about lexical resource gaps.

There is no off the shelf solution - afaik. In addition I have no idea how expensive running costs will be.

But something serviceable can be built.

Source: mod /t&s person dealing with these things