diff --git a/firmware/controllers/algo/engine_types.h b/firmware/controllers/algo/engine_types.h
index e51db4147f..294e21e53c 100644
--- a/firmware/controllers/algo/engine_types.h
+++ b/firmware/controllers/algo/engine_types.h
@@ -1,6 +1,9 @@
 /*
  * @file engine_types.h
  *
+ * See 'integration API' note in rusefi_enums.h
+ * TODO: spell out which enums belong here and which enums belong in rusefi_enums.h for what reasons
+ *
  * @date Oct 23, 2021
  * @author Andrey Belomutskiy, (c) 2012-2021
  */
diff --git a/firmware/controllers/algo/rusefi_enums.h b/firmware/controllers/algo/rusefi_enums.h
index 24939ac47e..bd1d9e4edb 100644
--- a/firmware/controllers/algo/rusefi_enums.h
+++ b/firmware/controllers/algo/rusefi_enums.h
@@ -1,6 +1,9 @@
 /**
  * @file	rusefi_enums.h
- * @brief	Fundamental rusEfi enumerable types live here
+ * @brief	Fundamental rusEFI enumerable types live here
+ *
+ * This and few over headers are part of integration API between C/C++ and code generator for memory meta and java code.
+ * TODO: move enums which should not be visible outside of the firmware out of 'integration API' headers like this one
  *
  * @note this file should probably not include any other files
  *