Update graph.py

graph.py

@@ -149,6 +149,7 @@ class EssayWriter:
     def save_workflow_graph(self):
         """Generate and save a Graphviz workflow visualization."""
         try:
+            import os
             dot = graphviz.Digraph(format="png")
             dot.attr(dpi='300')
 
@@ -167,9 +168,13 @@ class EssayWriter:
             dot.edge("Answer", "✅ Done")
 
             # Save Graph explicitly in PNG format
+            output_path = "graph.png"
             dot.render("graph", format="png", cleanup=True)
 
+            # Ensure file is available before Streamlit loads it
+            if not os.path.exists(output_path):
+                raise FileNotFoundError("Graphviz failed to generate the workflow graph.")
+
         except Exception as e:
             print(f"❌ Error generating workflow visualization: {e}")
 
-