BlueZ fills Device1.RSSI only while scanning; sensors connect to us, so the field stayed empty. MGMT_OP_GET_CONN_INFO (like btmgmt conn-info) returns the link RSSI; polled per connected sensor and after each write. Needs CAP_NET_ADMIN (AmbientCapabilities in the collector unit). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>