diff --git a/contexthub/aidl/android/hardware/contexthub/Service.aidl b/contexthub/aidl/android/hardware/contexthub/Service.aidl
index fd748c3..e107193 100644
--- a/contexthub/aidl/android/hardware/contexthub/Service.aidl
+++ b/contexthub/aidl/android/hardware/contexthub/Service.aidl
@@ -16,6 +16,17 @@
 
 package android.hardware.contexthub;
 
+/**
+ * Services that are provided by an endpoint.
+ *
+ * To support testing, the following service is defined here:
+ *  1. Test echo service:
+ *     - This service responds to a received message back to the sender with a
+ *       message with identical content as the received message.
+ *     - Format:                Service::RpcFormat::CUSTOM
+ *     - Service descriptor:    android.hardware.contexthub.test.EchoService
+ *     - Major version:         1
+ */
 @VintfStability
 parcelable Service {
     /**
diff --git a/contexthub/aidl/default/ContextHub.cpp b/contexthub/aidl/default/ContextHub.cpp
index 7eb51d0..80c9575 100644
--- a/contexthub/aidl/default/ContextHub.cpp
+++ b/contexthub/aidl/default/ContextHub.cpp
@@ -245,7 +245,7 @@
 
     Service echoService;
     echoService.format = Service::RpcFormat::CUSTOM;
-    echoService.serviceDescriptor = "ECHO";
+    echoService.serviceDescriptor = "android.hardware.contexthub.test.EchoService";
     echoService.majorVersion = 1;
     echoService.minorVersion = 0;