Server List Ping (0xFE)
Client to Server
To load server info in the multiplayer menu, the notchian client connects to each known server and sends an 0xFE.
In return, the server sends a kick (0xFF), with its string containing data (server description, number of users, number of slots), delimited by a UCS-2 '§' (0xA7).
Note that as this is the last packet you'll see, you can get away with just chopping off the first three bytes (the ident and the string length) and decoding the remainder as a UCS-2 string.
If the number of available slots sent is equal to or less than 0, the client should display it as "???".
Example server pinger: