diff --git a/Libplanet/Action/IAction.cs b/Libplanet/Action/IAction.cs
index 39ed6d15e3..c982cd0f9f 100644
--- a/Libplanet/Action/IAction.cs
+++ b/Libplanet/Action/IAction.cs
@@ -277,6 +277,13 @@ public interface IAction
/// or networking. These bring an action indeterministic. You maybe
/// fine to log messages for debugging purpose, but equivalent messages
/// could be logged multiple times.
+ /// Lastly, although it might be surprising, floating-point arithmetics are
+ /// underspecified so that it can make different results on different
+ /// machines, platforms, runtimes, compilers, and builds.
+ /// For more on determinism in general, please read also Tendermint ABCI's docs on determinism.
///
///
IAccountStateDelta Execute(IActionContext context);