diff --git a/contrib/fsm-to-dot.py b/contrib/fsm-to-dot.py
index 06d2df1..3e9678d 100755
--- a/contrib/fsm-to-dot.py
+++ b/contrib/fsm-to-dot.py
@@ -15,6 +15,10 @@
 
 import sys, re, os
 
+if '-h' in sys.argv or '--help' in sys.argv:
+  print(__doc__)
+  exit(0)
+
 def err(msg):
   sys.stderr.write(msg + '\n')