diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotSession.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotSession.kt
index 6ee6313c9..9408d2625 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotSession.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotSession.kt
@@ -58,6 +58,7 @@ expect class BotSession(
  * [BotSession] 平台通用基础
  */
 @MiraiInternalAPI
+// cannot be internal because of `public BotSession`
 abstract class BotSessionBase(
     val bot: Bot,
     val sessionKey: SessionKey,