diff --git a/mirai-core/src/main/java/net/mamoe/mirai/network/protocol/tim/packet/Packet.kt b/mirai-core/src/main/java/net/mamoe/mirai/network/protocol/tim/packet/Packet.kt
index 7a0d114c1..1da431920 100644
--- a/mirai-core/src/main/java/net/mamoe/mirai/network/protocol/tim/packet/Packet.kt
+++ b/mirai-core/src/main/java/net/mamoe/mirai/network/protocol/tim/packet/Packet.kt
@@ -6,7 +6,7 @@ package net.mamoe.mirai.network.protocol.tim.packet
 interface Packet
 
 
-object PacketNameFormatter {
+internal object PacketNameFormatter {
     @JvmSynthetic
     private var longestNameLength: Int = 43