Google's Calendar API cannot subscribe to an arbitrary ICS URL. This tool creates a native secondary Google calendar and mirrors events through the Events API instead. Mirrored events carry their AesthetiCal UID and revision in private extended properties, so repeated syncs update in place and deleted AesthetiCal events are removed without touching manually-created Google events.

node toolchain/calendar/gcal-sync.mjs auth   # one-time Google OAuth consent
node toolchain/calendar/gcal-sync.mjs enable-api # one-time project API enable
node toolchain/calendar/gcal-sync.mjs sync   # reconcile immediately
node toolchain/calendar/gcal-sync.mjs status
toolchain/calendar/install.sh                # sync every five minutes

The existing Desktop OAuth client is reused from aesthetic-computer-vault/youtube/client.json. Calendar-specific credentials and state live in the vault at:

aesthetic-computer-vault/calendar/google-token.json
aesthetic-computer-vault/calendar/state.json

The sync is intentionally one-way. Google edits are overwritten only when the corresponding AesthetiCal revision changes; Google-only events are untouched.