diff --git a/datmo/cli/command/task.py b/datmo/cli/command/task.py
index 72bd179c..23668593 100644
--- a/datmo/cli/command/task.py
+++ b/datmo/cli/command/task.py
@@ -25,12 +25,13 @@ def __init__(self, home, cli_helper):
             is the environment port available during a run.
         """)
         # run.add_argument("--data", nargs="*", dest="data", type=str, help="Path for data to be used during the Task")
-        run.add_argument("--env-def", dest="environment_definition_filepath", default="",
+        run.add_argument("--env-def", dest="environment_definition_filepath", default=None,
                          nargs="?", type=str,
                          help="Pass in the Dockerfile with which you want to build the environment")
         run.add_argument("--interactive", dest="interactive", action="store_true",
                          help="Run the environment in interactive mode (keeps STDIN open)")
-        run.add_argument("cmd", nargs="?", default=None)
+        run.add_argument("--cmd", "-c", dest="cmd", default=None, nargs="?",
+                         help="Pass in the command to be run inside container")
 
         # Task list arguments
         ls = subcommand_parsers.add_parser("ls", help="List tasks")
@@ -47,15 +48,14 @@ def run(self, **kwargs):
         self.cli_helper.echo(__("info", "cli.task.run"))
 
         # Create input dictionaries
-        snapshot_dict = {
-            "environment_definition_filepath":
+        snapshot_dict = {}
+        if kwargs['environment_definition_filepath']:
+            snapshot_dict["environment_definition_filepath"] =\
                 kwargs['environment_definition_filepath']
-        }
-
         if not isinstance(kwargs['cmd'], list):
             if platform.system() == "Windows":
                 kwargs['cmd'] = kwargs['cmd']
-            else:
+            elif type(kwargs['cmd']) is str:
                 kwargs['cmd'] = shlex.split(kwargs['cmd'])
 
         task_dict = {
diff --git a/datmo/cli/command/test/test_task.py b/datmo/cli/command/test/test_task.py
index 5e7ad208..03b7ad62 100644
--- a/datmo/cli/command/test/test_task.py
+++ b/datmo/cli/command/test/test_task.py
@@ -13,7 +13,6 @@
 #     import builtins as __builtin__
 
 import os
-import shutil
 import tempfile
 import platform
 from io import open
@@ -86,7 +85,7 @@ def test_datmo_task_run_should_fail2(self):
         self.task.parse([
             "task",
             "run",
-            test_command
+            "--cmd", test_command
         ])
         result = self.task.execute()
         assert not result
@@ -108,7 +107,7 @@ def test_datmo_task_run(self):
             "--ports", test_ports,
             "--env-def", test_dockerfile,
             "--interactive",
-            test_command
+            "--cmd", test_command
         ])
 
         # test for desired side effects
@@ -128,6 +127,27 @@ def test_datmo_task_run(self):
         assert result.results == {"accuracy": "0.45"}
         assert result.status == "SUCCESS"
 
+    def test_datmo_task_run_notebook(self):
+        self.__set_variables()
+        # Test success case
+        test_command = ["jupyter", "notebook", "list"]
+        test_ports = "8888:8888"
+
+        self.task.parse([
+            "task",
+            "run",
+            "--ports", test_ports,
+            "--cmd", test_command
+        ])
+
+        # test proper execution of task run command
+        result = self.task.execute()
+        assert result
+        assert isinstance(result, CoreTask)
+        assert result.logs
+        assert "Currently running servers" in result.logs
+        assert result.status == "SUCCESS"
+
     def test_task_run_invalid_arg(self):
         self.__set_variables()
         exception_thrown = False
@@ -182,7 +202,7 @@ def test_task_stop(self):
             "--ports", test_ports,
             "--env-def", test_dockerfile,
             "--interactive",
-            test_command
+            "--cmd", test_command
         ])
 
         test_task_obj = self.task.execute()
diff --git a/datmo/core/controller/environment/environment.py b/datmo/core/controller/environment/environment.py
index 21ee745b..4b26e33e 100644
--- a/datmo/core/controller/environment/environment.py
+++ b/datmo/core/controller/environment/environment.py
@@ -70,11 +70,10 @@ def create(self, dictionary):
         create_dict = {
             "model_id": self.model.id,
         }
-
         create_dict["driver_type"] = self.environment_driver.type
         create_dict["language"] = dictionary.get("language", None)
 
-        if "definition_filepath" in dictionary:
+        if "definition_filepath" in dictionary and dictionary['definition_filepath']:
             original_definition_filepath = dictionary['definition_filepath']
             # Split up the given path and save definition filename
             definition_path, definition_filename = \
diff --git a/datmo/core/controller/snapshot.py b/datmo/core/controller/snapshot.py
index f3ffe2d7..5fbdaad2 100644
--- a/datmo/core/controller/snapshot.py
+++ b/datmo/core/controller/snapshot.py
@@ -159,7 +159,6 @@ def create(self, incoming_dictionary):
             raise RequiredArgumentMissing(__("error",
                                              "controller.snapshot.create.arg",
                                              "message"))
-
         # Code setup
         self._code_setup(incoming_dictionary, create_dict)
 
@@ -306,7 +305,6 @@ def _env_setup(self, incoming_dictionary, create_dict):
         create_dict : dict
             dictionary for creating the Snapshot entity
         """
-
         language = incoming_dictionary.get("language", None)
         if "environment_id" in incoming_dictionary:
             create_dict['environment_id'] = incoming_dictionary['environment_id']
diff --git a/datmo/core/controller/task.py b/datmo/core/controller/task.py
index d29412d2..50c4c065 100644
--- a/datmo/core/controller/task.py
+++ b/datmo/core/controller/task.py
@@ -227,7 +227,6 @@ def run(self, task_id, snapshot_dict=None, task_dict=None):
             raise TaskRunException(__("error",
                                       "controller.task.run",
                                       task_dirpath))
-
         # Create the before snapshot prior to execution
         before_snapshot_dict = snapshot_dict.copy()
         before_snapshot_dict['message'] = "autogenerated snapshot created before task %s is run" % task_obj.id