--- a/PROTOCOL.md	Mon Aug 24 14:30:47 2026 +0200
+++ b/PROTOCOL.md	Mon Aug 24 14:31:37 2026 +0200
@@ -143,7 +143,6 @@
 | NETCODE_GAMEINFO     | 0x10 | yes          |
 | NETCODE_PGNDATA      | 0x11 | yes          |
 | NETCODE_MOVE         | 0x20 | yes          |
-| NETCODE_CHECK        | 0x22 | no           |
 | NETCODE_CHECKMATE    | 0x23 | no           |
 | NETCODE_STALEMATE    | 0x28 | no           |
 | NETCODE_NOMATERIAL   | 0x29 | no           |