diff --git a/star-lite/readme.md b/star-lite/readme.md
index 0b20470..695bb61 100644
--- a/star-lite/readme.md
+++ b/star-lite/readme.md
@@ -229,6 +229,8 @@ def verify(key_record_pairs, expected_root_cid):
     for (key, record) in key_record_pairs:
         record_cid = compute_cid(record)
         key_layer = layer_of(key)
+
+        # grow the stack if needed, init with empty nodes
         while len(stack) <= key_layer:
             stack.append(MstNode())
 
@@ -241,7 +243,9 @@ def verify(key_record_pairs, expected_root_cid):
                 stack[i + 1].attach_subtree(node_cid)
                 stack[i] = MstNode() # empty it
 
+        # every key-record pair must insert to a node `entry`
         stack[key_layer].entries.append(Leaf(key, record_cid, car_run=None))
+
         prev_layer = key_layer
 
     # Fold remaining stack bottom-up.