Per-user secret (users.calFeedToken) unlocks the FULL calendar (private incl.) over the public ICS endpoint — the AesthetiCal equivalent of Google's 'secret address in iCal format', so any calendar app can subscribe: GET /api/cal?code=<permahandle>&token=<secret>&format=ics Token is minted on first use, constant-time compared, never logged, and revocable. New surfaces: GET /api/cal?calToken=1 AUTH — return/mint the caller's link {token,code,url} POST /api/cal { rotateToken } AUTH — rotate (revokes old links) Inbound multi-connector feeds already existed (cal-feeds); this completes the hub: subscribe to aesthetical anywhere, pull any number of calendars into it.