diff --git a/src/js/dao/invitation-dao.js b/src/js/dao/invitation-dao.js
index 761a823..5fbfc97 100644
--- a/src/js/dao/invitation-dao.js
+++ b/src/js/dao/invitation-dao.js
@@ -23,12 +23,19 @@ define(function() {
 
     /**
      * Notes an invite for the recipient by the sender in the invitation web service
-     * @param {String} recipient User ID of the recipient
-     * @param {String} sender User ID of the sender
+     * @param {String} options.recipient User ID of the recipient
+     * @param {String} options.sender User ID of the sender
      * @param {Function} callback(error, status) Returns information if the invitation worked (INVITE_SUCCESS), if an invitation is already pendin (INVITE_PENDING), or information if an error occurred.
      */
-    InvitationDAO.prototype.invite = function(recipient, sender, callback) {
-        this._restDao.put(null, uri(recipient, sender), completed);
+    InvitationDAO.prototype.invite = function(options, callback) {
+        if (typeof options !== 'object' || typeof options.recipient !== 'string' || typeof options.recipient !== 'string') {
+            callback({
+                errMsg: 'erroneous usage of api: incorrect parameters!'
+            });
+            return;
+        }
+
+        this._restDao.put(null, uri(options.recipient, options.sender), completed);
 
         function completed(error, res, status) {
             if (error) {
@@ -52,12 +59,19 @@ define(function() {
 
     /**
      * Checks if an invitation for the recipient by the sender is present in the invitation web service
-     * @param {String} recipient User ID of the recipient
-     * @param {String} sender User ID of the sender
+     * @param {String} options.recipient User ID of the recipient
+     * @param {String} options.sender User ID of the sender
      * @param {Function} callback(error, status) Returns information about the invitation status, either an invitation is already on place (INVITE_PENDING), or not (INVITE_MISSING), or information if an error occurred.
      */
-    InvitationDAO.prototype.check = function(recipient, sender, callback) {
-        this._restDao.get(null, uri(recipient, sender), completed);
+    InvitationDAO.prototype.check = function(options, callback) {
+        if (typeof options !== 'object' || typeof options.recipient !== 'string' || typeof options.recipient !== 'string') {
+            callback({
+                errMsg: 'erroneous usage of api: incorrect parameters!'
+            });
+            return;
+        }
+
+        this._restDao.get(null, uri(options.recipient, options.sender), completed);
 
         function completed(error, res, status) {
             // 404 is a meaningful return value from the web service
diff --git a/test/new-unit/invitation-dao-test.js b/test/new-unit/invitation-dao-test.js
index 2645d1e..48d3568 100644
--- a/test/new-unit/invitation-dao-test.js
+++ b/test/new-unit/invitation-dao-test.js
@@ -30,7 +30,10 @@ define(function(require) {
             it('should invite the recipient', function(done) {
                 restDaoStub.put.yieldsAsync(null, undefined, 201);
 
-                invitationDao.invite(alice, bob, function(err, status) {
+                invitationDao.invite({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.not.exist;
                     expect(status).to.equal(InvitationDAO.INVITE_SUCCESS);
                     expect(restDaoStub.put.calledWith(null, expectedUri)).to.be.true;
@@ -41,7 +44,10 @@ define(function(require) {
             it('should point out already invited recipient', function(done) {
                 restDaoStub.put.yieldsAsync(null, undefined, 304);
 
-                invitationDao.invite(alice, bob, function(err, status) {
+                invitationDao.invite({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.not.exist;
                     expect(status).to.equal(InvitationDAO.INVITE_PENDING);
                     done();
@@ -53,7 +59,10 @@ define(function(require) {
                     errMsg: 'jawollja.'
                 });
 
-                invitationDao.invite(alice, bob, function(err, status) {
+                invitationDao.invite({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.exist;
                     expect(status).to.not.exist;
                     done();
@@ -63,19 +72,47 @@ define(function(require) {
             it('should not work for unexpected response', function(done) {
                 restDaoStub.put.yieldsAsync(null, undefined, 1337);
 
-                invitationDao.invite(alice, bob, function(err, status) {
+                invitationDao.invite({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.exist;
                     expect(status).to.not.exist;
                     done();
                 });
             });
+
+            it('should report erroneous usage', function() {
+                invitationDao.invite({
+                    sender: bob
+                }, expectError);
+
+                invitationDao.invite({
+                    recipient: alice,
+                }, expectError);
+                
+                invitationDao.invite({
+                    recipient: 123,
+                    sender: 123
+                }, expectError);
+                
+                invitationDao.invite('asd', expectError);
+
+                function expectError(err, status) {
+                    expect(err).to.exist;
+                    expect(status).to.not.exist;
+                }
+            });
         });
 
         describe('check', function() {
             it('should return pending invite', function(done) {
                 restDaoStub.get.yieldsAsync(null, undefined, 200);
 
-                invitationDao.check(alice, bob, function(err, status) {
+                invitationDao.check({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.not.exist;
                     expect(status).to.equal(InvitationDAO.INVITE_PENDING);
                     expect(restDaoStub.get.calledWith(null, expectedUri)).to.be.true;
@@ -88,7 +125,10 @@ define(function(require) {
                     code: 404
                 });
 
-                invitationDao.check(alice, bob, function(err, status) {
+                invitationDao.check({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.not.exist;
                     expect(status).to.equal(InvitationDAO.INVITE_MISSING);
                     done();
@@ -101,7 +141,10 @@ define(function(require) {
                     errMsg: 'jawollja.'
                 });
 
-                invitationDao.check(alice, bob, function(err, status) {
+                invitationDao.check({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.exist;
                     expect(status).to.not.exist;
                     done();
@@ -111,12 +154,37 @@ define(function(require) {
             it('should not work for unexpected response', function(done) {
                 restDaoStub.get.yieldsAsync(null, undefined, 1337);
 
-                invitationDao.check(alice, bob, function(err, status) {
+                invitationDao.check({
+                    recipient: alice,
+                    sender: bob
+                }, function(err, status) {
                     expect(err).to.exist;
                     expect(status).to.not.exist;
                     done();
                 });
             });
+
+            it('should report erroneous usage', function() {
+                invitationDao.check({
+                    sender: bob
+                }, expectError);
+
+                invitationDao.check({
+                    recipient: alice,
+                }, expectError);
+                
+                invitationDao.check({
+                    recipient: 123,
+                    sender: 123
+                }, expectError);
+                
+                invitationDao.check('asd', expectError);
+
+                function expectError(err, status) {
+                    expect(err).to.exist;
+                    expect(status).to.not.exist;
+                }
+            });
         });
     });
 });
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