If you mean this https://www.espruino.com/Reference#l_BluetoothRemoteGATTServer_setRSSIHandler then the documentation says something else. However the other side (=Pi5) already has its own rssi value for the connection to the Puck so why to send it from Puck to the Pi? Maybe describe what you are trying to do.
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If you mean this https://www.espruino.com/Reference#l_BluetoothRemoteGATTServer_setRSSIHandler then the documentation says something else. However the other side (=Pi5) already has its own rssi value for the connection to the Puck so why to send it from Puck to the Pi? Maybe describe what you are trying to do.