diff --git a/IPython/html/services/kernels/handlers.py b/IPython/html/services/kernels/handlers.py
index 693e05a..147e2a7 100644
--- a/IPython/html/services/kernels/handlers.py
+++ b/IPython/html/services/kernels/handlers.py
@@ -23,7 +23,7 @@ from zmq.utils import jsonapi
 
 from IPython.utils.jsonutil import date_default
 
-from ...base.handlers import IPythonHandler
+from ...base.handlers import IPythonHandler, json_errors
 from ...base.zmqhandlers import AuthenticatedZMQStreamHandler
 
 #-----------------------------------------------------------------------------
@@ -34,11 +34,13 @@ from ...base.zmqhandlers import AuthenticatedZMQStreamHandler
 class MainKernelHandler(IPythonHandler):
 
     @web.authenticated
+    @json_errors
     def get(self):
         km = self.kernel_manager
-        self.finish(jsonapi.dumps(km.list_kernels()))
+        self.finish(jsonapi.dumps(km.list_kernels(self.ws_url)))
 
     @web.authenticated
+    @json_errors
     def post(self):
         km = self.kernel_manager
         kernel_id = km.start_kernel()
@@ -52,12 +54,14 @@ class KernelHandler(IPythonHandler):
     SUPPORTED_METHODS = ('DELETE', 'GET')
 
     @web.authenticated
+    @json_errors
     def get(self, kernel_id):
         km = self.kernel_manager
         model = km.kernel_model(kernel_id, self.ws_url)
         self.finish(jsonapi.dumps(model))
 
     @web.authenticated
+    @json_errors
     def delete(self, kernel_id):
         km = self.kernel_manager
         km.shutdown_kernel(kernel_id)
@@ -68,6 +72,7 @@ class KernelHandler(IPythonHandler):
 class KernelActionHandler(IPythonHandler):
 
     @web.authenticated
+    @json_errors
     def post(self, kernel_id, action):
         km = self.kernel_manager
         if action == 'interrupt':
diff --git a/IPython/html/services/kernels/kernelmanager.py b/IPython/html/services/kernels/kernelmanager.py
index 8535d3f..787abd1 100644
--- a/IPython/html/services/kernels/kernelmanager.py
+++ b/IPython/html/services/kernels/kernelmanager.py
@@ -79,9 +79,14 @@ class MappingKernelManager(MultiKernelManager):
         model = {"id":kernel_id, "ws_url": ws_url}
         return model
 
-    def list_kernels(self):
+    def list_kernels(self, ws_url):
         """Returns a list of kernel_id's of kernels running."""
-        return super(MappingKernelManager, self).list_kernel_ids()
+        kernels = []
+        kernel_ids = super(MappingKernelManager, self).list_kernel_ids()
+        for kernel_id in kernel_ids:
+            model = self.kernel_model(kernel_id, ws_url)
+            kernels.append(model)
+        return kernels
 
     # override _check_kernel_id to raise 404 instead of KeyError
     def _check_kernel_id(self, kernel_id):
diff --git a/IPython/html/services/kernels/tests/test_kernels_api.py b/IPython/html/services/kernels/tests/test_kernels_api.py
index 707bdf1..894717f 100644
--- a/IPython/html/services/kernels/tests/test_kernels_api.py
+++ b/IPython/html/services/kernels/tests/test_kernels_api.py
@@ -36,7 +36,7 @@ class KernelAPITest(NotebookTestBase):
         # GET request
         r = requests.get(self.base_url())
         assert isinstance(r.json(), list)
-        self.assertEqual(r.json()[0], data['id'])
+        self.assertEqual(r.json()[0]['id'], data['id'])
 
     def test_kernel_handler(self):
         # GET kernel with id
diff --git a/IPython/html/services/notebooks/filenbmanager.py b/IPython/html/services/notebooks/filenbmanager.py
index e7d0d08..bbf2d85 100644
--- a/IPython/html/services/notebooks/filenbmanager.py
+++ b/IPython/html/services/notebooks/filenbmanager.py
@@ -228,8 +228,8 @@ class FileNotebookManager(NotebookManager):
                 self.log.debug("Unlinking checkpoint %s", cp_path)
                 os.unlink(cp_path)
         
-        self.log.debug("Unlinking notebook %s", nb_path)
-        os.unlink(nb_path)
+        self.log.debug("Unlinking notebook %s", os_path)
+        os.unlink(os_path)
 
     def rename_notebook(self, old_name, old_path, new_name, new_path):
         """Rename a notebook."""