diff --git a/docs/learning_grpc.md b/docs/learning_grpc.md
index dc45aa1..7acf159 100644
--- a/docs/learning_grpc.md
+++ b/docs/learning_grpc.md
@@ -229,6 +229,8 @@ enum CustomerDeclineRenewalReason {
 
 note:
 
+- We use the IDL to define the structure of our protos
+
 - Fields are uniquely identified with a numeric tag.
 
 - When deleting fields, their tag must be marked as reserved to ensure its never used again