diff --git a/src/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions/IHistoryProvider.cs b/src/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions/IHistoryProvider.cs
index 70e089bd..6a337153 100644
--- a/src/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions/IHistoryProvider.cs
+++ b/src/Core/ZB.MOM.WW.OtOpcUa.Core.Abstractions/IHistoryProvider.cs
@@ -95,9 +95,10 @@ public interface IHistoryProvider
///
/// Request cancellation.
///
- /// Default implementation throws. Only drivers with an event historian (Galaxy via the
- /// Wonderware Alarm & Events log) override. Modbus / the OPC UA Client driver stay
- /// with the default and let callers see BadHistoryOperationUnsupported.
+ /// Default implementation throws. Drivers whose backend can serve historical events
+ /// override: Galaxy (Wonderware Alarm & Events log) and the OPC UA Client driver
+ /// (forwarding HistoryReadEvents to its upstream server). Raw-only drivers such as Modbus
+ /// stay with the default and let callers see BadHistoryOperationUnsupported.
///
/// Note the type asymmetry with /
/// (both use uint maxValuesPerNode): event