diff --git a/include/asterisk/sorcery.h b/include/asterisk/sorcery.h
index 464a83c83148086df07fc6fd7c08b44892234055..85d7456153c5e2ba0c40f6fc0d344fea313eb626 100644
--- a/include/asterisk/sorcery.h
+++ b/include/asterisk/sorcery.h
@@ -588,6 +588,8 @@ int ast_sorcery_diff(const struct ast_sorcery *sorcery, const void *original, co
  *
  * \retval 0 success
  * \retval -1 failure
+ *
+ * \note You must be ready to accept observer invocations before this function is called
  */
 int ast_sorcery_observer_add(const struct ast_sorcery *sorcery, const char *type, const struct ast_sorcery_observer *callbacks);