Hammerstein vs Claude for Solo RPGs
You could take Claude, or any general AI, and try to turn it into a GM. You will write the instructions yourself, then test it game after game to catch the places where it invents an answer rather than admit it has none.
No yes-anding
Hammerstein runs the rules and the world. You play your character. Bad plans can fail. No yes-anding, no ten-paragraph scenery, no amnesia at turn eleven.
Seeded dice
Rolls are real and shown. RPG mode rolls off a seeded tape you can check after the fact.
Persistent state
Hammerstein keeps your state between sessions: inventory, wounds, counters.