Up to four concrete tweaks for a graded run, each with a plain-words why and a FULL patched spec the member can apply with one click.

AI proposes; NOTHING auto-applies; the engine re-grades on the member's click. A tweak whose spec does not validate keeps its explanation and loses its Apply button — we never hand back a spec that cannot run.

Session-cookie only (an account key pair gains no AI access). 404 on a missing or foreign run — byte-identical either way, so probing another member's ids tells a stranger nothing.