diff --git a/commonspace/object/tree/objecttree/objecttree.go b/commonspace/object/tree/objecttree/objecttree.go
index f6c63053..013a9540 100644
--- a/commonspace/object/tree/objecttree/objecttree.go
+++ b/commonspace/object/tree/objecttree/objecttree.go
@@ -235,11 +235,19 @@ func (ot *objectTree) AddContentWithValidator(ctx context.Context, content Signa
 	oldHeads = append(oldHeads, ot.tree.Heads()...)
 
 	objChange, rawChange, err := ot.changeBuilder.Build(payload)
+	if err != nil {
+		return
+	}
+	// validating the change just in case to avoid possible bugs
+	err = ot.validateTree([]*Change{objChange})
+	if err != nil {
+		err = fmt.Errorf("error validating added change: %w", err)
+		return
+	}
 	if content.IsSnapshot {
 		// clearing tree, because we already saved everything in the last snapshot
 		ot.tree = &Tree{}
 	}
-
 	if validator != nil {
 		err = validator(rawChange)
 		if err != nil {