diff --git a/lib/ansible/errors/__init__.py b/lib/ansible/errors/__init__.py
index 2acdefab0b..97ee3fc413 100644
--- a/lib/ansible/errors/__init__.py
+++ b/lib/ansible/errors/__init__.py
@@ -46,7 +46,7 @@ class AnsibleError(Exception):
     which should be returned by the DataLoader() class.
     '''
 
-    def __init__(self, message="", obj=None, show_content=True, suppress_extended_error=False):
+    def __init__(self, message="", obj=None, show_content=True, suppress_extended_error=False, orig_exc=None):
         # we import this here to prevent an import loop problem,
         # since the objects code also imports ansible.errors
         from ansible.parsing.yaml.objects import AnsibleBaseYAMLObject
@@ -61,6 +61,10 @@ class AnsibleError(Exception):
                 self.message = '%s' % to_native(message)
         else:
             self.message = '%s' % to_native(message)
+        if orig_exc:
+            self.orig_exc = orig_exc
+            self.message += '\nexception type: %s' % to_native(type(orig_exc))
+            self.message += '\nexception: %s' % to_native(orig_exc)
 
     def __str__(self):
         return self.message
diff --git a/lib/ansible/parsing/dataloader.py b/lib/ansible/parsing/dataloader.py
index c436926339..9d40a3d6b0 100644
--- a/lib/ansible/parsing/dataloader.py
+++ b/lib/ansible/parsing/dataloader.py
@@ -186,7 +186,7 @@ class DataLoader:
             return (data, show_content)
 
         except (IOError, OSError) as e:
-            raise AnsibleParserError("an error occurred while trying to read the file '%s': %s" % (file_name, str(e)))
+            raise AnsibleParserError("an error occurred while trying to read the file '%s': %s" % (file_name, str(e)), orig_exc=e)
 
     def _handle_error(self, yaml_exc, file_name, show_content):
         '''
@@ -202,12 +202,7 @@ class DataLoader:
             err_obj = AnsibleBaseYAMLObject()
             err_obj.ansible_pos = (file_name, yaml_exc.problem_mark.line + 1, yaml_exc.problem_mark.column + 1)
 
-        if hasattr(yaml_exc, 'problem'):
-            err_str = "%s\nThe YAML error was:\n > %s" % (YAML_SYNTAX_ERROR.strip(), yaml_exc.problem)
-        else:
-            err_str = YAML_SYNTAX_ERROR
-
-        raise AnsibleParserError(err_str, obj=err_obj, show_content=show_content)
+        raise AnsibleParserError(YAML_SYNTAX_ERROR, obj=err_obj, show_content=show_content, orig_exc=yaml_exc)
 
     def get_basedir(self):
         ''' returns the current basedir '''
@@ -424,7 +419,7 @@ class DataLoader:
             return real_path
 
         except (IOError, OSError) as e:
-            raise AnsibleParserError("an error occurred while trying to read the file '%s': %s" % (to_native(real_path), to_native(e)))
+            raise AnsibleParserError("an error occurred while trying to read the file '%s': %s" % (to_native(real_path), to_native(e)), orig_exc=e)
 
     def cleanup_tmp_file(self, file_path):
         """
diff --git a/lib/ansible/parsing/mod_args.py b/lib/ansible/parsing/mod_args.py
index d48a3d2468..ad0bf9c70a 100644
--- a/lib/ansible/parsing/mod_args.py
+++ b/lib/ansible/parsing/mod_args.py
@@ -95,8 +95,9 @@ class ModuleArgsParser:
     Args may also be munged for certain shell command parameters.
     """
 
+    # FIXME: mutable default arg
     def __init__(self, task_ds=dict()):
-        assert isinstance(task_ds, dict)
+        assert isinstance(task_ds, dict), "the type of 'task_ds' should be a dict, but is a %s" % type(task_ds)
         self._task_ds = task_ds
 
     def _split_module_string(self, module_string):
diff --git a/lib/ansible/parsing/splitter.py b/lib/ansible/parsing/splitter.py
index 5008dd3a6a..0adb4bf84b 100644
--- a/lib/ansible/parsing/splitter.py
+++ b/lib/ansible/parsing/splitter.py
@@ -62,7 +62,7 @@ def parse_kv(args, check_raw=False):
             vargs = split_args(args)
         except ValueError as ve:
             if 'no closing quotation' in str(ve).lower():
-                raise AnsibleParserError("error parsing argument string, try quoting the entire line.")
+                raise AnsibleParserError("error parsing argument string, try quoting the entire line.", orig_exc=ve)
             else:
                 raise
 
diff --git a/lib/ansible/parsing/yaml/constructor.py b/lib/ansible/parsing/yaml/constructor.py
index 0e3a21acb9..6753089283 100644
--- a/lib/ansible/parsing/yaml/constructor.py
+++ b/lib/ansible/parsing/yaml/constructor.py
@@ -99,7 +99,10 @@ class AnsibleConstructor(SafeConstructor):
         ciphertext_data = to_bytes(value)
 
         if self._b_vault_password is None:
-            raise ConstructorError(None, None, "found vault but no vault password provided", node.start_mark)
+            raise ConstructorError(context=None, context_mark=None,
+                                   problem="found !vault but no vault password provided",
+                                   problem_mark=node.start_mark,
+                                   note=None)
 
         # could pass in a key id here to choose the vault to associate with
         vault = self._vaults['default']
diff --git a/lib/ansible/parsing/yaml/objects.py b/lib/ansible/parsing/yaml/objects.py
index 41df711a81..9991381132 100644
--- a/lib/ansible/parsing/yaml/objects.py
+++ b/lib/ansible/parsing/yaml/objects.py
@@ -70,7 +70,7 @@ class AnsibleSequence(AnsibleBaseYAMLObject, list):
 
 # Unicode like object that is not evaluated (decrypted) until it needs to be
 # TODO: is there a reason these objects are subclasses for YAMLObject?
-class AnsibleVaultEncryptedUnicode(yaml.YAMLObject, AnsibleUnicode):
+class AnsibleVaultEncryptedUnicode(yaml.YAMLObject, AnsibleBaseYAMLObject):
     __UNSAFE__ = True
     __ENCRYPTED__ = True
     yaml_tag = u'!vault'
diff --git a/lib/ansible/playbook/base.py b/lib/ansible/playbook/base.py
index cdafd5f25d..38091172fd 100644
--- a/lib/ansible/playbook/base.py
+++ b/lib/ansible/playbook/base.py
@@ -220,7 +220,7 @@ class Base(with_metaclass(BaseMeta, object)):
     def load_data(self, ds, variable_manager=None, loader=None):
         ''' walk the input datastructure and assign any values '''
 
-        assert ds is not None
+        assert ds is not None, 'ds (%s) should not be None but it is.' % ds
 
         # cache the datastructure internally
         setattr(self, '_ds', ds)
@@ -440,12 +440,12 @@ class Base(with_metaclass(BaseMeta, object)):
                 setattr(self, name, value)
 
             except (TypeError, ValueError) as e:
-                raise AnsibleParserError("the field '%s' has an invalid value (%s), and could not be converted to an %s. "
-                                         "The error was: %s" % (name, value, attribute.isa, e), obj=self.get_ds())
+                raise AnsibleParserError("the field '%s' has an invalid value (%s), and could not be converted to an %s."
+                                         "The error was: %s" % (name, value, attribute.isa, e), obj=self.get_ds(), orig_exc=e)
             except (AnsibleUndefinedVariable, UndefinedError) as e:
                 if templar._fail_on_undefined_errors and name != 'name':
-                    raise AnsibleParserError("the field '%s' has an invalid value, which appears to include a variable that is undefined. "
-                                             "The error was: %s" % (name, e), obj=self.get_ds())
+                    raise AnsibleParserError("the field '%s' has an invalid value, which appears to include a variable that is undefined."
+                                             "The error was: %s" % (name, e), obj=self.get_ds(), orig_exc=e)
 
         self._finalized = True
 
@@ -477,10 +477,11 @@ class Base(with_metaclass(BaseMeta, object)):
                 return {}
             else:
                 raise ValueError
-        except ValueError:
-            raise AnsibleParserError("Vars in a %s must be specified as a dictionary, or a list of dictionaries" % self.__class__.__name__, obj=ds)
+        except ValueError as e:
+            raise AnsibleParserError("Vars in a %s must be specified as a dictionary, or a list of dictionaries" % self.__class__.__name__,
+                                     obj=ds, orig_exc=e)
         except TypeError as e:
-            raise AnsibleParserError("Invalid variable name in vars specified for %s: %s" % (self.__class__.__name__, e), obj=ds)
+            raise AnsibleParserError("Invalid variable name in vars specified for %s: %s" % (self.__class__.__name__, e), obj=ds, orig_exc=e)
 
     def _extend_value(self, value, new_value, prepend=False):
         '''
@@ -554,7 +555,7 @@ class Base(with_metaclass(BaseMeta, object)):
         and extended.
         '''
 
-        assert isinstance(data, dict)
+        assert isinstance(data, dict), 'data (%s) should be a dict but is a %s' % (data, type(data))
 
         for (name, attribute) in iteritems(self._valid_attrs):
             if name in data:
diff --git a/lib/ansible/playbook/block.py b/lib/ansible/playbook/block.py
index 432db55339..85c5f8b96e 100644
--- a/lib/ansible/playbook/block.py
+++ b/lib/ansible/playbook/block.py
@@ -121,8 +121,8 @@ class Block(Base, Become, Conditional, Taggable):
                 loader=self._loader,
                 use_handlers=self._use_handlers,
             )
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading a block", obj=self._ds, orig_exc=e)
 
     def _load_rescue(self, attr, ds):
         try:
@@ -136,8 +136,8 @@ class Block(Base, Become, Conditional, Taggable):
                 loader=self._loader,
                 use_handlers=self._use_handlers,
             )
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading rescue.", obj=self._ds, orig_exc=e)
 
     def _load_always(self, attr, ds):
         try:
@@ -151,8 +151,8 @@ class Block(Base, Become, Conditional, Taggable):
                 loader=self._loader,
                 use_handlers=self._use_handlers,
             )
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading always", obj=self._ds, orig_exc=e)
 
     def get_dep_chain(self):
         if self._dep_chain is None:
diff --git a/lib/ansible/playbook/helpers.py b/lib/ansible/playbook/helpers.py
index c347a80713..ab08b6ecc4 100644
--- a/lib/ansible/playbook/helpers.py
+++ b/lib/ansible/playbook/helpers.py
@@ -43,7 +43,7 @@ def load_list_of_blocks(ds, play, parent_block=None, role=None, task_include=Non
     from ansible.playbook.task_include import TaskInclude
     from ansible.playbook.role_include import IncludeRole
 
-    assert isinstance(ds, (list, type(None)))
+    assert isinstance(ds, (list, type(None))), '%s should be a list or None but is %s' % (ds, type(ds))
 
     block_list = []
     if ds:
@@ -89,11 +89,11 @@ def load_list_of_tasks(ds, play, block=None, role=None, task_include=None, use_h
     from ansible.playbook.handler_task_include import HandlerTaskInclude
     from ansible.template import Templar
 
-    assert isinstance(ds, list)
+    assert isinstance(ds, list), 'The ds (%s) should be a list but was a %s' % (ds, type(ds))
 
     task_list = []
     for task_ds in ds:
-        assert isinstance(task_ds, dict)
+        assert isinstance(task_ds, dict), 'The ds (%s) should be a dict but was a %s' % (ds, type(ds))
 
         if 'block' in task_ds:
             t = Block.load(
@@ -190,7 +190,7 @@ def load_list_of_tasks(ds, play, block=None, role=None, task_include=None, use_h
                     if not found:
                         try:
                             include_target = templar.template(t.args['_raw_params'])
-                        except AnsibleUndefinedVariable:
+                        except AnsibleUndefinedVariable as e:
                             raise AnsibleParserError(
                                 "Error when evaluating variable in include name: %s.\n\n"
                                 "When using static includes, ensure that any variables used in their names are defined in vars/vars_files\n"
@@ -198,7 +198,7 @@ def load_list_of_tasks(ds, play, block=None, role=None, task_include=None, use_h
                                 "sources like group or host vars." % t.args['_raw_params'],
                                 obj=task_ds,
                                 suppress_extended_error=True,
-                            )
+                                orig_exc=e)
                         if t._role:
                             include_file = loader.path_dwim_relative(t._role._role_path, subdir, include_target)
                         else:
@@ -341,7 +341,7 @@ def load_list_of_roles(ds, play, current_role_path=None, variable_manager=None,
     # we import here to prevent a circular dependency with imports
     from ansible.playbook.role.include import RoleInclude
 
-    assert isinstance(ds, list)
+    assert isinstance(ds, list), 'ds (%s) should be a list but was a %s' % (ds, type(ds))
 
     roles = []
     for role_def in ds:
diff --git a/lib/ansible/playbook/play.py b/lib/ansible/playbook/play.py
index f0a87b8a79..b9b5e3d3ac 100644
--- a/lib/ansible/playbook/play.py
+++ b/lib/ansible/playbook/play.py
@@ -121,7 +121,7 @@ class Play(Base, Taggable, Become):
         Adjusts play datastructure to cleanup old/legacy items
         '''
 
-        assert isinstance(ds, dict)
+        assert isinstance(ds, dict), 'while preprocessing data (%s), ds should be a dict but was a %s' % (ds, type(ds))
 
         # The use of 'user' in the Play datastructure was deprecated to
         # line up with the same change for Tasks, due to the fact that
@@ -145,8 +145,8 @@ class Play(Base, Taggable, Become):
         '''
         try:
             return load_list_of_blocks(ds=ds, play=self, variable_manager=self._variable_manager, loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading tasks", obj=self._ds, orig_exc=e)
 
     def _load_pre_tasks(self, attr, ds):
         '''
@@ -155,8 +155,8 @@ class Play(Base, Taggable, Become):
         '''
         try:
             return load_list_of_blocks(ds=ds, play=self, variable_manager=self._variable_manager, loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading pre_tasks", obj=self._ds, orig_exc=e)
 
     def _load_post_tasks(self, attr, ds):
         '''
@@ -165,8 +165,8 @@ class Play(Base, Taggable, Become):
         '''
         try:
             return load_list_of_blocks(ds=ds, play=self, variable_manager=self._variable_manager, loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading post_tasks", obj=self._ds, orig_exc=e)
 
     def _load_handlers(self, attr, ds):
         '''
@@ -175,8 +175,8 @@ class Play(Base, Taggable, Become):
         '''
         try:
             return load_list_of_blocks(ds=ds, play=self, use_handlers=True, variable_manager=self._variable_manager, loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed block was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed block was encountered while loading handlers", obj=self._ds, orig_exc=e)
 
     def _load_roles(self, attr, ds):
         '''
@@ -189,8 +189,8 @@ class Play(Base, Taggable, Become):
 
         try:
             role_includes = load_list_of_roles(ds, play=self, variable_manager=self._variable_manager, loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed role declaration was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed role declaration was encountered.", obj=self._ds, orig_exc=e)
 
         roles = []
         for ri in role_includes:
diff --git a/lib/ansible/playbook/playbook_include.py b/lib/ansible/playbook/playbook_include.py
index 04423ff6ec..fc5a32bf7b 100644
--- a/lib/ansible/playbook/playbook_include.py
+++ b/lib/ansible/playbook/playbook_include.py
@@ -105,7 +105,7 @@ class PlaybookInclude(Base, Conditional, Taggable):
         up with what we expect the proper attributes to be
         '''
 
-        assert isinstance(ds, dict)
+        assert isinstance(ds, dict), 'ds (%s) should be a dict but was a %s' % (ds, type(ds))
 
         # the new, cleaned datastructure, which will have legacy
         # items reduced to a standard structure
diff --git a/lib/ansible/playbook/role/__init__.py b/lib/ansible/playbook/role/__init__.py
index 2c1d485fb3..d9805b00fa 100644
--- a/lib/ansible/playbook/role/__init__.py
+++ b/lib/ansible/playbook/role/__init__.py
@@ -209,16 +209,18 @@ class Role(Base, Become, Conditional, Taggable):
         if task_data:
             try:
                 self._task_blocks = load_list_of_blocks(task_data, play=self._play, role=self, loader=self._loader, variable_manager=self._variable_manager)
-            except AssertionError:
-                raise AnsibleParserError("The tasks/main.yml file for role '%s' must contain a list of tasks" % self._role_name, obj=task_data)
+            except AssertionError as e:
+                raise AnsibleParserError("The tasks/main.yml file for role '%s' must contain a list of tasks" % self._role_name,
+                                         obj=task_data, orig_exc=e)
 
         handler_data = self._load_role_yaml('handlers')
         if handler_data:
             try:
                 self._handler_blocks = load_list_of_blocks(handler_data, play=self._play, role=self, use_handlers=True, loader=self._loader,
                                                            variable_manager=self._variable_manager)
-            except AssertionError:
-                raise AnsibleParserError("The handlers/main.yml file for role '%s' must contain a list of tasks" % self._role_name, obj=handler_data)
+            except AssertionError as e:
+                raise AnsibleParserError("The handlers/main.yml file for role '%s' must contain a list of tasks" % self._role_name,
+                                         obj=handler_data, orig_exc=e)
 
         # vars and default vars are regular dictionaries
         self._role_vars = self._load_role_yaml('vars', main=self._from_files.get('vars'))
diff --git a/lib/ansible/playbook/role/metadata.py b/lib/ansible/playbook/role/metadata.py
index 28e1728ebd..1a9df75634 100644
--- a/lib/ansible/playbook/role/metadata.py
+++ b/lib/ansible/playbook/role/metadata.py
@@ -80,7 +80,7 @@ class RoleMetadata(Base):
                         role_def['name'] = def_parsed['name']
                     roles.append(role_def)
                 except AnsibleError as exc:
-                    raise AnsibleParserError(str(exc), obj=role_def)
+                    raise AnsibleParserError(str(exc), obj=role_def, orig_exc=exc)
 
         current_role_path = None
         if self._owner:
@@ -89,8 +89,8 @@ class RoleMetadata(Base):
         try:
             return load_list_of_roles(roles, play=self._owner._play, current_role_path=current_role_path, variable_manager=self._variable_manager,
                                       loader=self._loader)
-        except AssertionError:
-            raise AnsibleParserError("A malformed list of role dependencies was encountered.", obj=self._ds)
+        except AssertionError as e:
+            raise AnsibleParserError("A malformed list of role dependencies was encountered.", obj=self._ds, orig_exc=e)
 
     def _load_galaxy_info(self, attr, ds):
         '''
diff --git a/lib/ansible/playbook/task.py b/lib/ansible/playbook/task.py
index a40cd79b28..a88a78a1b3 100644
--- a/lib/ansible/playbook/task.py
+++ b/lib/ansible/playbook/task.py
@@ -161,7 +161,7 @@ class Task(Base, Conditional, Taggable, Become):
         keep it short.
         '''
 
-        assert isinstance(ds, dict)
+        assert isinstance(ds, dict), 'ds (%s) should be a dict but was a %s' % (ds, type(dict))
 
         # the new, cleaned datastructure, which will have legacy
         # items reduced to a standard structure suitable for the
@@ -177,7 +177,7 @@ class Task(Base, Conditional, Taggable, Become):
         try:
             (action, args, delegate_to) = args_parser.parse()
         except AnsibleParserError as e:
-            raise AnsibleParserError(to_native(e), obj=ds)
+            raise AnsibleParserError(to_native(e), obj=ds, orig_exc=e)
 
         # the command/shell/script modules used to support the `cmd` arg,
         # which corresponds to what we now call _raw_params, so move that
diff --git a/lib/ansible/template/__init__.py b/lib/ansible/template/__init__.py
index c9129a31d5..19741a997a 100644
--- a/lib/ansible/template/__init__.py
+++ b/lib/ansible/template/__init__.py
@@ -385,7 +385,7 @@ class Templar:
         are being changed.
         '''
 
-        assert isinstance(variables, dict)
+        assert isinstance(variables, dict), "the type of 'variables' should be a dict but was a %s" % (type(variables))
         self._available_variables = variables
         self._cached_result = {}
 
diff --git a/lib/ansible/vars/manager.py b/lib/ansible/vars/manager.py
index 47d9fb27b7..6747dff377 100644
--- a/lib/ansible/vars/manager.py
+++ b/lib/ansible/vars/manager.py
@@ -142,7 +142,7 @@ class VariableManager:
     @extra_vars.setter
     def extra_vars(self, value):
         ''' ensures a clean copy of the extra_vars are used to set the value '''
-        assert isinstance(value, MutableMapping)
+        assert isinstance(value, MutableMapping), "the type of 'value' for extra_vars should be a MutableMapping, but is a %s" % type(value)
         self._extra_vars = value.copy()
 
     def set_inventory(self, inventory):
@@ -156,7 +156,7 @@ class VariableManager:
     @options_vars.setter
     def options_vars(self, value):
         ''' ensures a clean copy of the options_vars are used to set the value '''
-        assert isinstance(value, dict)
+        assert isinstance(value, dict), "the type of 'value' for options_vars should be a dict, but is a %s" % type(value)
         self._options_vars = value.copy()
 
     def _preprocess_vars(self, a):
@@ -577,7 +577,7 @@ class VariableManager:
         Sets or updates the given facts for a host in the fact cache.
         '''
 
-        assert isinstance(facts, dict)
+        assert isinstance(facts, dict), "the type of 'facts' to set for host_facts should be a dict but is a %s" % type(facts)
 
         if host.name not in self._fact_cache:
             self._fact_cache[host.name] = facts
@@ -592,7 +592,7 @@ class VariableManager:
         Sets or updates the given facts for a host in the fact cache.
         '''
 
-        assert isinstance(facts, dict)
+        assert isinstance(facts, dict), "the type of 'facts' to set for nonpersistent_facts should be a dict but is a %s" % type(facts)
 
         if host.name not in self._nonpersistent_fact_cache:
             self._nonpersistent_fact_cache[host.name] = facts