Home Assistant — Entity Lifecycle and Registries

Entity Lifecycle

1. Platform discovery: async_setup_entry called on platform
2. Entity creation: Entities instantiated, passed to async_add_entities
3. Registration: HA assigns entity_id, registers in entity registry
4. First update: async_added_to_hass called, initial state written
5. Updates: Coordinator triggers _handle_coordinator_update
6. Removal: async_will_remove_from_hass for cleanup

from homeassistant.helpers.restore_state import RestoreEntity