diff --git a/README.md b/README.md
index cf30994..7c7b847 100644
--- a/README.md
+++ b/README.md
@@ -18,3 +18,4 @@ Usage
     }).then(function(response) {
       console.log(response);
     });
+
diff --git a/requestError.js b/requestError.js
index e252e3c..10dc9bf 100644
--- a/requestError.js
+++ b/requestError.js
@@ -1,17 +1,14 @@
 'use strict';
 
-var _ = require('lodash');
-
 var SuiteRequestError = function(message, code, data) {
   this.message = message;
   this.name = 'SuiteRequestError';
   this.code = code;
-  this.data = {
-    replyText: message
-  };
-  this.stack = new Error().stack;
-
-  _.extend(this, data);
+  this.data = data || {};
+  if (!this.data.replyText) {
+    this.data.replyText = message;
+  }
+  this.stack = new Error(message).stack;
 };
 
 SuiteRequestError.prototype = Object.create(Error.prototype);
diff --git a/requestError.spec.js b/requestError.spec.js
new file mode 100644
index 0000000..5e451c7
--- /dev/null
+++ b/requestError.spec.js
@@ -0,0 +1,25 @@
+'use strict';
+
+var SuiteRequestError = require('./requestError');
+
+describe('SuiteRequestError', function() {
+  it('should extend base Error class', function() {
+    var error = new SuiteRequestError();
+
+    expect(error).to.be.an.instanceOf(Error);
+  });
+
+  it('should store constructor parameters', function() {
+    var error = new SuiteRequestError('Invalid request', 400, { detailedMessage: 'Line too long' });
+
+    expect(error.message).to.eql('Invalid request');
+    expect(error.code).to.eql(400);
+    expect(error.data).to.eql({ detailedMessage: 'Line too long', replyText: 'Invalid request' });
+  });
+
+  it('should always contain replyText in data', function() {
+    var error = new SuiteRequestError('Unauthorized');
+
+    expect(error.data.replyText).to.eql('Unauthorized');
+  });
+});