Encrypted state cookies solve real problems (server-side storage, latency, scaling) and are not the problem. The problem is insufficient binding of some of a s

Encrypted state cookies solve real problems (server-side storage, latency, scaling) and are not the problem. The problem is insufficient binding of some of a session's encrypted state cookies and others -- insufficient binding of some session state to other session state. Here we have HTTP encrypted state cookies for identifying authenticate user IDs and maybe for identifying sessions / chats, while the reasoning traces are also encrypted state cookies but not HTTP cookies, and the latter are somehow not sufficiently bound to the former. The fix is to either have per-user or per-session keys for encrypting reasoning traces, or write the user ID / account ID and maybe also session ID into the plaintext of the reasoning trace _then check that that matches the ones in the HTTP cookies when decrypting the traces_.