diff --git a/README.md b/README.md
new file mode 100644
index 0000000..4bc7f05
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+# HackFinder
+* Usage: java -jar HackFinder.jar <mods dir> <log file>
diff --git a/src/main/java/ru/zaxar163/hackfinder/ModScan.java b/src/main/java/ru/zaxar163/hackfinder/ModScan.java
index ed77f7a..a188de2 100644
--- a/src/main/java/ru/zaxar163/hackfinder/ModScan.java
+++ b/src/main/java/ru/zaxar163/hackfinder/ModScan.java
@@ -15,6 +15,10 @@
 
 public class ModScan {
 	public static void main(final String[] args) throws FileNotFoundException {
+		if (args.length < 2) {
+			System.out.println("Usage: <mods dir> <log file>");
+			System.exit(1);
+		}
 		final File mods = new File(args[0]);
 		try (PrintStream log = new PrintStream(new FileOutputStream(args[1]))) {
 			Arrays.stream(mods.listFiles()).filter(e -> e.getName().endsWith(".jar") || e.getName().endsWith(".zip"))