diff --git a/client/commands.go b/client/commands.go
index e49faca..0e935a5 100644
--- a/client/commands.go
+++ b/client/commands.go
@@ -292,7 +292,8 @@ func (conn *Conn) Ping(message string) { conn.Raw(PING + " :" + message) }
 func (conn *Conn) Pong(message string) { conn.Raw(PONG + " :" + message) }
 
 // Cap sends a CAP command to the server.
-//     CAP capability
+//     CAP subcommand
+//     CAP subcommand :message
 func (conn *Conn) Cap(subcommmand string, message ...string) {
 	if len(message) == 0 {
 		conn.Raw(CAP + " " + subcommmand)