diff --git a/README.md b/README.md
index 710470f..4cab59a 100644
--- a/README.md
+++ b/README.md
@@ -8,8 +8,7 @@ Extract data from INSEE number (France)
 pyenv virtualenv 3.9.6 insee
 pyenv local insee
 poetry install
-python insee_number_translator/main.py
-python insee_number_translator/main.py 123456789123456
+insee 269059913116714 168127982980507
 ```
 
 ## Data sources
diff --git a/insee_number_translator/main.py b/insee_number_translator/main.py
index e1c49f1..9f80214 100644
--- a/insee_number_translator/main.py
+++ b/insee_number_translator/main.py
@@ -152,14 +152,15 @@ class InseeData:
 
 
 def main():
-    numbers = ["269059913116714", "168127982980507"]
     if len(sys.argv) > 1:
         numbers = sys.argv[1:]
+    else:
+        print(f"Usage: {sys.argv[0]} insee_number_1 [insee_number_2 ...]")
+        sys.exit(1)
     for number in numbers:
         data = InseeData(number)
         print(data)
         pprint.pprint(data.to_dict())
-        print("\n\n")
 
 
 if __name__ == "__main__":