diff --git a/src/app/clusters/general-diagnostics-server/general-diagnostics-server.cpp b/src/app/clusters/general-diagnostics-server/general-diagnostics-server.cpp
index 0b598104fb83e9..108cc0b7d7357f 100644
--- a/src/app/clusters/general-diagnostics-server/general-diagnostics-server.cpp
+++ b/src/app/clusters/general-diagnostics-server/general-diagnostics-server.cpp
@@ -204,6 +204,7 @@ CHIP_ERROR GeneralDiagosticsAttrAccess::Read(const ConcreteReadAttributePath & a
         bool isTestEventTriggersEnabled = IsTestEventTriggerEnabled();
         return aEncoder.Encode(isTestEventTriggersEnabled);
     }
+    // Note: Attribute ID 0x0009 was removed (#30002).
     default: {
         break;
     }