diff --git a/core/src/main/com/sinch/sdk/core/http/AuthManager.java b/core/src/main/com/sinch/sdk/core/http/AuthManager.java
index c376d040..02429cca 100644
--- a/core/src/main/com/sinch/sdk/core/http/AuthManager.java
+++ b/core/src/main/com/sinch/sdk/core/http/AuthManager.java
@@ -5,6 +5,7 @@
 
 public interface AuthManager {
 
+  // expected schemes identifier defined at OAS files level
   String SCHEMA_KEYWORD_BEARER = "Bearer";
   String SCHEMA_KEYWORD_BASIC = "Basic";