diff --git a/setup.py b/setup.py
index b288de0..72fad80 100644
--- a/setup.py
+++ b/setup.py
@@ -6,13 +6,13 @@ from setuptools import setup
 
 setup(
     name = 'slideslurp',
-    version = '0.0.2',
+    version = '0.0.3',
     description = 'SlideShare to PDF',
     author = 'Veit Heller',
     author_email = 'veit@veitheller.de',
     license = 'MIT License',
     url = 'https://github.com/hellerve/slideslurp',
-    download_url = 'https://github.com/hellerve/slideslurp/tarball/0.0.2',
+    download_url = 'https://github.com/hellerve/slideslurp/tarball/0.0.3',
     packages = find_packages('.'),
     install_requires=[
         "bs4",
diff --git a/slideslurp/__init__.py b/slideslurp/__init__.py
index 50edc5b..ce83fc6 100644
--- a/slideslurp/__init__.py
+++ b/slideslurp/__init__.py
@@ -7,6 +7,9 @@ from reportlab.pdfgen import canvas
 
 
 def main():
+    if not len(sys.argv) == 2:
+        print("Usage: slideslurp <url>")
+        sys.exit(1)
     url = sys.argv[1]
 
     res = requests.get(url)