diff --git a/src/blue_cwl/core/viz.py b/src/blue_cwl/core/viz.py
index f116d55..524a7c8 100644
--- a/src/blue_cwl/core/viz.py
+++ b/src/blue_cwl/core/viz.py
@@ -9,7 +9,7 @@
 
 
 def show_workflow_graph_image(cwl_workflow):
-    """Show workflow graph."""
+    """Show Workflow graph."""
     graph = _build_workflow_graph(cwl_workflow)
 
     png_str = graph.create_png()  # pylint: disable=no-member