better cli

recipes.py

@@ -485,6 +485,22 @@ class Builder:
         return 0
 
 
+def help() -> None:
+    print(f"usage: {sys.argv[0]} build DIR - build pages in DIR/out")
+    print(f"       {sys.argv[0]} -h        - show help")
+
+
+def main() -> None:
+    if len(sys.argv) == 2 and sys.argv[1] == "-h":
+        help()
+        sys.exit(0)
+    elif len(sys.argv) == 3 and sys.argv[1] == "build":
+        ret = Builder().build(sys.argv[2])
+        sys.exit(ret)
+    else:
+        help()
+        sys.exit(1)
+
+
 if __name__ == "__main__":
-    builder = Builder()
-    sys.exit(builder.build("recipes"))
+    main()