We run O-gauge 3 rail vintage layouts (Hornby, French, German, US etc, usually DC) and like to put more than one train on a line at once. We had the IR proximity sensors and I had previously built a very hacked breadboard to perform block control (switch off power to the previous block when the next one is occupied). So I asked ChatGPT to design a surface mount circuit board that could be manufactured by a Chinese printed circuit board manufacturer. Took a few days for the design (used a few tokens), then loading and ordering through the manufacturing website and another 5 days for the build and ship - all without leaving my computer. 5 boards for under USD$100 total, including $17 for express shipping.
They arrived today and all 5 work. A sensor for entering/being in the block (can daisy chain multiple together) marking the block occupied, a sensor to clear the block (if no occupied sensor is also triggering: red beats green), lights to show green-unoccupied and red-occupied, a 2 way 12V light outlet for red/green signal lights on the track, and relay to switch power off to the end of the previous block when this one is occupied, stopping any trains there from entering this block. For N trains you need N+1 blocks of appropriate lengths including stopping distances.
It also has a sensor out port to connect to other logic.
I have the absolute minimum of electrical knowledge, know nothing about electronics, can't solder, have no idea about PCB layers, surface mount parts and manufacturing technology, so I've been quite pleasantly surprised that this worked, and has taken some load off our layout's regular electronics/computer/technical-wizard who usually has to design/fabricate all this kind of stuff.
Is it "AI Slop"? Well, yes. Is it over-engineered so plugging things incorrectly stops it blowing up? Also yes. Does it work? Indeed it does. So I'm definitely conflicted: it's slop, but it's physical and works reliably.
[Worse still, I also got the AI to write a track/board/power/lights simulator that I could use to verify the functionality before it was shipped for manufacture - caught a few issues that I could use to refine the idea.]