diff --git a/executables/nr-cuup.c b/executables/nr-cuup.c
index 978486f261..856dcd6152 100644
--- a/executables/nr-cuup.c
+++ b/executables/nr-cuup.c
@@ -172,6 +172,7 @@ int main(int argc, char **argv)
   MessageDef *msg = RCconfig_NR_CU_E1(&e1type);
   AssertFatal(msg != NULL, "Send init to task for E1AP UP failed\n");
   itti_send_msg_to_task(TASK_CUUP_E1, 0, msg);
+  LOG_D(E1AP, "Send E1AP REGISTER REQ to TASK_CUUP_E1\n");
 
   #ifdef E2_AGENT
   //////////////////////////////////
diff --git a/openair2/E1AP/e1ap_setup.c b/openair2/E1AP/e1ap_setup.c
index fc59a881fa..c27e1bd112 100644
--- a/openair2/E1AP/e1ap_setup.c
+++ b/openair2/E1AP/e1ap_setup.c
@@ -67,6 +67,17 @@ static void get_NGU_S1U_addr(char **addr, uint16_t *port)
   return;
 }
 
+/**
+ * @brief Prepares an E1AP_REGISTER_REQ message for gNB-CU-UP/CP registration
+ *
+ * This function creates and populates an E1AP_REGISTER_REQ message using system
+ * configuration parameters. It supports both integrated CU-CP/UP and E1 splits,
+ * fetching RAN, PLMN, NSSAIs, and network configuration.
+ *
+ * @param entity Specifies the entity type (CU-CP or CU-UP. If NULL, assumes integrated CU-CP/UP
+ *
+ * @return A pointer to the E1AP_REGISTER_REQ message or NULL on allocation failure
+ */
 MessageDef *RCconfig_NR_CU_E1(const E1_t *entity)
 {
   MessageDef *msgConfig = itti_alloc_new_message(TASK_GNB_APP, 0, E1AP_REGISTER_REQ);