diff --git a/README.md b/README.md
index 4642e82..c8beb13 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,10 @@ validate(minifiedCode, [sourceMap], [sourceContent]);
  * `sourceContent` is a map to the raw source files
     * Optional - If left empty, the inline `sourceContent` in `sourceMap` will be used
 
+### CLI Usage
+
+    sourcemap-validate $minifiedFilePath $sourceMapFilePath
+
 ## Examples
 
 ```js
diff --git a/index.js b/index.js
index 39ad676..41762e0 100644
--- a/index.js
+++ b/index.js
@@ -1,7 +1,9 @@
+#!/usr/bin/env node
 var validate
   , validateMapping
   , toAscii
   , assert = require('assert')
+  , fs = require('fs')
   , SMConsumer = require('source-map').SourceMapConsumer
   , each = require('lodash.foreach')
   , template = require('lodash.template')
@@ -74,7 +76,7 @@ validate = function (min, map, srcs) {
     consumer = new SMConsumer(map);
   }
   catch (e) {
-    throw new Error('The map is not valid JSON');
+    throw new Error('The map is not valid JSON: ' + e);
   }
 
   each(consumer.sources, function (src) {
@@ -159,4 +161,10 @@ validate = function (min, map, srcs) {
   assert.ok(mappingCount > 0, 'There were no mappings in the file');
 };
 
+// "main" entrypoint:
+if (typeof require !== 'undefined' && require.main === module) {
+    validate(fs.readFileSync(process.argv[2], 'utf-8'), fs.readFileSync(process.argv[3], 'utf-8'));
+    process.stdout.write("Validation OK");
+}
+
 module.exports = validate;
diff --git a/package.json b/package.json
index b6223b0..55e5fc9 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,9 @@
   "scripts": {
     "test": "jake test --trace"
   },
+  "bin": {
+    "sourcemap-validate": "./index.js"
+  },
   "devDependencies": {
     "jake": "0.7.x",
     "uglify-js": "2.4.x"