Google and Stanford engineers just dropped a 39-page PDF on what actually makes an AI agent self-improve.

input → output → feedback → update → repeat

the number it opens with: only 9% of agents run a real loop.

the other 91% is a human typing the next prompt by hand.

their case: a loop isn't a vibe, it's three hidden choices

• starting artifact

• credit horizon

• experience batching

i spent weeks getting these three right.

now my loop runs while i sleep and rewrites its own skill file so it never asks me twice.

the paper says why 91% of loops quietly die. the article is the one that didn't.