The guidelines demonstrate that it isn't merely show and tell: https://news.ycombinator.com/showhn.html

    On topic: things people can run on their computers or hold in their hands. For hardware, you can post a video or detailed article. For books, a sample chapter is ok.
    Off topic: blog posts, sign-up pages, newsletters, lists, and other reading material. Those can't be tried out, so can't be Show HNs. Make a regular submission instead.
    The project should be non-trivial. Don't post quickly-generated one-offs; anybody can do that now. Share something that is deeply personal and interesting to you.
    Explain how and why.

Also see dang's comments on the validity of various submissions:

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...

And in particular this comment that touches on AI submissions in particular (https://news.ycombinator.com/item?id=48118727) from which I provide an excerpt:

    In software it's fascinating how configuration management (that boringest of all phrases) is becoming the hard part. How do you share and version the source? 
    What even is the source? Is it the prompts? That's where the OP heads at the end: "share it somewhere — or, better yet, just a screenshot and the prompts you 
    used to make it." But when I floated a couple trial balloons about whether we might use this for Show HN—i.e., don't just share the code you generated, 
    because that's not the source anymore; instead share the prompts—we got a lot of pushback from knowledgeable people 
    (summarized here: https://news.ycombinator.com/item?id=47213630).

The topic is supposed to be narrow. It's supposed to be more than just show and tell, and definitely not "whatever the person wants."

Show HN: A working 3D model of an Enigma machine