diff --git a/todos/Jupyter-OpenBIS-extension todos.md b/todos/Jupyter-OpenBIS-extension todos.md
index 7b51fc65b31337372178efbd013399a1251b6b70..3e3ad02ec84f6e35837f415fb8de3c001fc43385 100644
--- a/todos/Jupyter-OpenBIS-extension todos.md	
+++ b/todos/Jupyter-OpenBIS-extension todos.md	
@@ -17,9 +17,10 @@
 
 
 ## 3) Uploading datasets
+   
    - let the upload dialog box stay in place until the upload was successful
-   - if metadata is faulty, tell the user to correct them (e.g. invalid vocabulary)
-   - show which metadata is mandatory and which are optional
+   - if metadata is faulty, tell the user to correct them (e.g. invalid vocabulary). This involves the backend to check as much as possible.
+   - show which metadata is mandatory and which are optional. Mandatory metadata is marked as such in the propertyAssignments that are fetched from the backend (e.g. `"mandatory:true`)
    - if dataset type is changed back and forth, keep the values that already have been entered
    - keep choice of current dataset type