Connect to a MI FlowerCare sensor

That document mentions handles. Ideally you'd have the actual characteristic UUIDs to use - perhaps you could write some code for Puck.js that uses BluetoothRemoteGATTService.getCharacteri­stics() in order to get a list of the characteristics with their handles?

Worst case, you could actually create a new http://www.espruino.com/Reference#Blueto­othRemoteGATTCharacteristic class with the internal handle variables set to the handles mentioned in that document, and then set them up as it says?