diff --git a/jedi/_compatibility.py b/jedi/_compatibility.py
index ad1d83c9..c3a2ff54 100644
--- a/jedi/_compatibility.py
+++ b/jedi/_compatibility.py
@@ -220,14 +220,14 @@ except AttributeError:
     encoding = 'ascii'
 
 
-def u(string):
+def u(string, errors='strict'):
     """Cast to unicode DAMMIT!
     Written because Python2 repr always implicitly casts to a string, so we
     have to cast back to a unicode (and we now that we always deal with valid
     unicode, because we check that in the beginning).
     """
     if isinstance(string, bytes):
-        return str(string, encoding='UTF-8')
+        return unicode(string, encoding='UTF-8', errors=errors)
     return string
 
 
diff --git a/jedi/api/keywords.py b/jedi/api/keywords.py
index bf43c99c..c217641a 100644
--- a/jedi/api/keywords.py
+++ b/jedi/api/keywords.py
@@ -73,7 +73,7 @@ keywords_only_valid_as_leaf = (
 
 
 class KeywordName(AbstractNameDefinition):
-    api_type = 'keyword'
+    api_type = u'keyword'
 
     def __init__(self, evaluator, name):
         self.evaluator = evaluator
@@ -88,7 +88,7 @@ class KeywordName(AbstractNameDefinition):
 
 
 class Keyword(object):
-    api_type = 'keyword'
+    api_type = u'keyword'
 
     def __init__(self, evaluator, name, pos):
         self.name = KeywordName(evaluator, name)
diff --git a/jedi/evaluate/compiled/access.py b/jedi/evaluate/compiled/access.py
index aaea4567..9d1cfefd 100644
--- a/jedi/evaluate/compiled/access.py
+++ b/jedi/evaluate/compiled/access.py
@@ -5,7 +5,7 @@ import operator as op
 from collections import namedtuple
 
 from jedi import debug
-from jedi._compatibility import unicode, is_py3, is_py34, builtins, py_version
+from jedi._compatibility import unicode, is_py3, is_py34, builtins, py_version, u
 from jedi.evaluate.compiled.getattr_static import getattr_static
 from jedi.evaluate.utils import dotted_from_fs_path
 
@@ -192,7 +192,7 @@ class DirectObjectAccess(object):
             return None
 
     def py__doc__(self, include_call_signature=False):
-        return inspect.getdoc(self._obj) or ''
+        return u(inspect.getdoc(self._obj), errors='replace') or u''
 
     def py__name__(self):
         if not _is_class_instance(self._obj) or \
@@ -300,14 +300,14 @@ class DirectObjectAccess(object):
     def get_api_type(self):
         obj = self._obj
         if self.is_class():
-            return 'class'
+            return u'class'
         elif inspect.ismodule(obj):
-            return 'module'
+            return u'module'
         elif inspect.isbuiltin(obj) or inspect.ismethod(obj) \
                 or inspect.ismethoddescriptor(obj) or inspect.isfunction(obj):
-            return 'function'
+            return u'function'
         # Everything else...
-        return 'instance'
+        return u'instance'
 
     def get_access_path_tuples(self):
         return [
diff --git a/jedi/evaluate/compiled/context.py b/jedi/evaluate/compiled/context.py
index e00881f2..2b492b10 100644
--- a/jedi/evaluate/compiled/context.py
+++ b/jedi/evaluate/compiled/context.py
@@ -236,7 +236,7 @@ class CompiledName(AbstractNameDefinition):
 
 
 class SignatureParamName(AbstractNameDefinition):
-    api_type = 'param'
+    api_type = u'param'
 
     def __init__(self, compiled_obj, signature_param):
         self.parent_context = compiled_obj.parent_context
@@ -259,7 +259,7 @@ class SignatureParamName(AbstractNameDefinition):
 
 
 class UnresolvableParamName(AbstractNameDefinition):
-    api_type = 'param'
+    api_type = u'param'
 
     def __init__(self, compiled_obj, name):
         self.parent_context = compiled_obj.parent_context
diff --git a/jedi/evaluate/context/function.py b/jedi/evaluate/context/function.py
index 7af1a438..8fb8389b 100644
--- a/jedi/evaluate/context/function.py
+++ b/jedi/evaluate/context/function.py
@@ -39,7 +39,7 @@ class FunctionContext(use_metaclass(CachedMetaClass, TreeContext)):
     """
     Needed because of decorators. Decorators are evaluated here.
     """
-    api_type = 'function'
+    api_type = u'function'
 
     def __init__(self, evaluator, parent_context, funcdef):
         """ This should not be called directly """
diff --git a/jedi/evaluate/context/instance.py b/jedi/evaluate/context/instance.py
index 9bb7d9ef..ebb004e6 100644
--- a/jedi/evaluate/context/instance.py
+++ b/jedi/evaluate/context/instance.py
@@ -39,7 +39,7 @@ class AbstractInstanceContext(Context):
     """
     This class is used to evaluate instances.
     """
-    api_type = 'instance'
+    api_type = u'instance'
     function_execution_cls = InstanceFunctionExecution
 
     def __init__(self, evaluator, parent_context, class_context, var_args):
diff --git a/jedi/evaluate/context/iterable.py b/jedi/evaluate/context/iterable.py
index 6d9a127c..65f7cb09 100644
--- a/jedi/evaluate/context/iterable.py
+++ b/jedi/evaluate/context/iterable.py
@@ -41,7 +41,7 @@ from jedi.parser_utils import get_comp_fors
 
 class AbstractIterable(Context):
     builtin_methods = {}
-    api_type = 'instance'
+    api_type = u'instance'
 
     def __init__(self, evaluator):
         super(AbstractIterable, self).__init__(evaluator, evaluator.builtins_module)
diff --git a/jedi/evaluate/context/klass.py b/jedi/evaluate/context/klass.py
index c96873e3..4a645f45 100644
--- a/jedi/evaluate/context/klass.py
+++ b/jedi/evaluate/context/klass.py
@@ -89,7 +89,7 @@ class ClassContext(use_metaclass(CachedMetaClass, TreeContext)):
     This class is not only important to extend `tree.Class`, it is also a
     important for descriptors (if the descriptor methods are evaluated or not).
     """
-    api_type = 'class'
+    api_type = u'class'
 
     def __init__(self, evaluator, parent_context, classdef):
         super(ClassContext, self).__init__(evaluator, parent_context=parent_context)
diff --git a/jedi/evaluate/context/module.py b/jedi/evaluate/context/module.py
index 3083b46f..9833207a 100644
--- a/jedi/evaluate/context/module.py
+++ b/jedi/evaluate/context/module.py
@@ -18,7 +18,7 @@ class _ModuleAttributeName(AbstractNameDefinition):
     """
     For module attributes like __file__, __str__ and so on.
     """
-    api_type = 'instance'
+    api_type = u'instance'
 
     def __init__(self, parent_module, string_name):
         self.parent_context = parent_module
@@ -42,7 +42,7 @@ class ModuleName(ContextNameMixin, AbstractNameDefinition):
 
 
 class ModuleContext(use_metaclass(CachedMetaClass, TreeContext)):
-    api_type = 'module'
+    api_type = u'module'
     parent_context = None
 
     def __init__(self, evaluator, module_node, path):
diff --git a/jedi/evaluate/context/namespace.py b/jedi/evaluate/context/namespace.py
index 7ae0624c..ba615e1b 100644
--- a/jedi/evaluate/context/namespace.py
+++ b/jedi/evaluate/context/namespace.py
@@ -27,7 +27,7 @@ class ImplicitNamespaceContext(TreeContext):
     """
     Provides support for implicit namespace packages
     """
-    api_type = 'module'
+    api_type = u'module'
     parent_context = None
 
     def __init__(self, evaluator, fullname, paths):
diff --git a/jedi/evaluate/filters.py b/jedi/evaluate/filters.py
index b1bc5800..40f7d846 100644
--- a/jedi/evaluate/filters.py
+++ b/jedi/evaluate/filters.py
@@ -108,7 +108,7 @@ class TreeNameDefinition(AbstractTreeName):
 
 
 class ParamName(AbstractTreeName):
-    api_type = 'param'
+    api_type = u'param'
 
     def __init__(self, parent_context, tree_name):
         self.parent_context = parent_context
@@ -281,7 +281,7 @@ class DictFilter(AbstractFilter):
 
 class _BuiltinMappedMethod(Context):
     """``Generator.__next__`` ``dict.values`` methods and so on."""
-    api_type = 'function'
+    api_type = u'function'
 
     def __init__(self, builtin_context, method, builtin_func):
         super(_BuiltinMappedMethod, self).__init__(
@@ -304,7 +304,7 @@ class SpecialMethodFilter(DictFilter):
     classes like Generator (for __next__, etc).
     """
     class SpecialMethodName(AbstractNameDefinition):
-        api_type = 'function'
+        api_type = u'function'
 
         def __init__(self, parent_context, string_name, callable_, builtin_context):
             self.parent_context = parent_context