diff --git a/src/ifcopenshell-python/ifcopenshell/entity_instance.py b/src/ifcopenshell-python/ifcopenshell/entity_instance.py
index 5e0426364b..476ed11784 100644
--- a/src/ifcopenshell-python/ifcopenshell/entity_instance.py
+++ b/src/ifcopenshell-python/ifcopenshell/entity_instance.py
@@ -204,6 +204,7 @@ class entity_instance:
             vs = entity_instance.wrap_value(self.wrapped_data.get_inverse(name), self.wrapped_data.file)
             if settings.unpack_non_aggregate_inverses:
                 schema_name = self.wrapped_data.is_a(True).split(".")[0]
+                ent: ifcopenshell_wrapper.entity
                 ent = ifcopenshell_wrapper.schema_by_name(schema_name).declaration_by_name(self.is_a())
                 inv = [i for i in ent.all_inverse_attributes() if i.name() == name][0]
                 if (inv.bound1(), inv.bound2()) == (-1, -1):
diff --git a/src/ifcopenshell-python/ifcopenshell/ifcopenshell_wrapper.pyi b/src/ifcopenshell-python/ifcopenshell/ifcopenshell_wrapper.pyi
index 9cb135c48f..c84b252f30 100644
--- a/src/ifcopenshell-python/ifcopenshell/ifcopenshell_wrapper.pyi
+++ b/src/ifcopenshell-python/ifcopenshell/ifcopenshell_wrapper.pyi
@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
-from typing import Any, Union
+from typing import Any, Union, Literal
 
 # `std::vector<xxx>` usually translated to `tuple[xxx, ...]`.
 
@@ -569,7 +569,7 @@ class aggregation_type(parameter_type):
     def bound2(self): ...
     def type_of_aggregation(self): ...
     def type_of_aggregation_string(self): ...
-    def type_of_element(self): ...
+    def type_of_element(self) -> parameter_type: ...
 
 class attribute:
     def name(self) -> str: ...
@@ -708,13 +708,16 @@ class cylinder(surface):
 
 class declaration:
     def _is(self, *args: str) -> bool: ...
-    def as_entity(self): ...
-    def as_enumeration_type(self): ...
-    def as_select_type(self): ...
-    def as_type_declaration(self): ...
-    def index_in_schema(self): ...
+    def as_entity(self) -> Union[entity, None]: ...
+    def as_enumeration_type(self) -> Union[enumeration_type, None]: ...
+    def as_select_type(self) -> Union[select_type, None]: ...
+    def as_type_declaration(self) -> Union[type_declaration, None]: ...
+    def index_in_schema(self) -> int: ...
     def name(self) -> str: ...
-    def name_uc(self): ...
+    def name_uc(self) -> str:
+        """Get name in upper case."""
+        ...
+
     def schema(self) -> schema_definition: ...
     def type(self): ...
 
@@ -745,40 +748,63 @@ class ellipse(curve):
 
 class entity(declaration):
     def all_attributes(self) -> tuple[attribute, ...]: ...
-    def all_inverse_attributes(self): ...
-    def argument_types(self): ...
-    def as_entity(self): ...
+    def all_inverse_attributes(self) -> tuple[inverse_attribute, ...]: ...
+    def argument_types(self) -> tuple[str, ...]:
+        """Get a tuple of types for each attribute in ``all_attributes()``."""
+        ...
+
+    def as_entity(self) -> entity: ...
     def attribute_by_index(self, index: int) -> attribute: ...
     def attribute_count(self) -> int: ...
-    def attribute_index(self, *args): ...
-    def attributes(self): ...
+    def attribute_index(self, *args: Union[str, attribute]) -> int:
+        """
+        :param args: A single attribute name / attribute.
+        """
+        ...
+
+    def attributes(self) -> tuple[attribute, ...]: ...
     def derived(self) -> tuple[bool, ...]:
         """Return a tuple of booleans indicating whether each direct attribute is derived."""
         ...
 
-    def is_abstract(self): ...
+    def is_abstract(self) -> bool: ...
     def set_attributes(self, attributes, derived): ...
     def set_inverse_attributes(self, inverse_attributes): ...
     def set_subtypes(self, subtypes): ...
-    def subtypes(self): ...
-    def supertype(self): ...
+    def subtypes(self) -> tuple[entity, ...]: ...
+    def supertype(self) -> Union[entity, None]: ...
 
 class entity_instance:
     file_: Any
     id_: Any
     def data(self, *args): ...
-    def declaration(self): ...
-    def file_pointer(self): ...
+    def declaration(self) -> declaration: ...
+    def file_pointer(self):
+        """Internal IfcFile pointer address."""
+        ...
+
     def get_argument(self, *args): ...
     def get_argument_index(self, a): ...
     def get_argument_name(self, i): ...
     def get_argument_type(self, i): ...
-    def get_attribute_category(self, name): ...
+    def get_attribute_category(self, name: str) -> Literal[0, 1, 2]:
+        """Get attribute category id.
+
+        Available categories:
+        - `0` - invalid attribute
+        - `1` - forward attribute
+        - `2` - inverse attributes
+        """
+        ...
+
     def get_attribute_names(self): ...
     def get_inverse(self, a): ...
     def get_inverse_attribute_names(self): ...
-    def id(self): ...
-    def identity(self): ...
+    def id(self) -> int: ...
+    def identity(self) -> int:
+        """Entity instance identity, unique across all opened IFC files during current session."""
+        ...
+
     def is_a(self, *args): ...
     def setArgumentAsAggregateOfAggregateOfDouble(self, i, v): ...
     def setArgumentAsAggregateOfAggregateOfEntityInstance(self, i, v): ...
@@ -799,11 +825,16 @@ class entity_instance:
     def unset_attribute_value(self, i): ...
 
 class enumeration_type(declaration):
-    def argument_types(self): ...
-    def as_enumeration_type(self): ...
-    def enumeration_items(self): ...
-    def lookup_enum_offset(self, string): ...
-    def lookup_enum_value(self, i): ...
+    def argument_types(self) -> tuple[str, ...]: ...
+    def as_enumeration_type(self) -> enumeration_type: ...
+    def enumeration_items(self) -> tuple[str, ...]: ...
+    def lookup_enum_offset(self, string: str) -> int:
+        """Get index of the string in enum."""
+        ...
+
+    def lookup_enum_value(self, i: int) -> str:
+        """Get a string for the index in enum."""
+        ...
 
 class extrusion(sweep):
     depth: Any
@@ -843,7 +874,10 @@ class file:
     @staticmethod
     def createTimestamp(): ...
     def entity_names(self): ...
-    def file_pointer(self): ...
+    def file_pointer(self) -> int:
+        """Internal IfcFile pointer address."""
+        ...
+
     def getInverse(self, instance_id, type, attribute_index): ...
     def getMaxId(self): ...
     def getTotalInverses(self, instance_id): ...
@@ -861,7 +895,7 @@ class file:
     @staticmethod
     def guid_map(*args): ...
     @property
-    def header(self): ...
+    def header(self) -> IfcSpfHeader: ...
     def ifcroot_type(self): ...
     def instance_by_guid(self, guid): ...
     def instances_by_reference(self, id): ...
@@ -1131,18 +1165,29 @@ class revolve(sweep):
     def matrix(self): ...
 
 class schema_definition:
-    def declaration_by_name(self, *args: str) -> declaration: ...
-    def declarations(self) -> tuple[declaration, ...]: ...
+    def declaration_by_name(self, *args: str) -> declaration:
+        """
+        :return: ``declaration`` but upcasted to the most advanced available type
+            (e.g. ``entity``, ``type_declaration``, etc).
+        """
+        ...
+
+    def declarations(self) -> tuple[declaration, ...]:
+        """
+        :return: returned declarations are also upcasted, see ``declaration_by_name``.
+        """
+        ...
+
     def entities(self) -> tuple[entity, ...]: ...
-    def enumeration_types(self): ...
+    def enumeration_types(self) -> tuple[enumeration_type, ...]: ...
+    def select_types(self) -> tuple[select_type, ...]: ...
+    def type_declarations(self) -> tuple[type_declaration, ...]: ...
     def instantiate(self, decl, data): ...
     def name(self) -> str: ...
-    def select_types(self): ...
-    def type_declarations(self): ...
 
 class select_type(declaration):
-    def as_select_type(self): ...
-    def select_list(self): ...
+    def as_select_type(self) -> select_type: ...
+    def select_list(self) -> tuple[declaration, ...]: ...
 
 class shell:
     closed: Any
@@ -1424,7 +1469,7 @@ class type_by_kind:
 
 class type_declaration(declaration):
     def argument_types(self): ...
-    def as_type_declaration(self): ...
+    def as_type_declaration(self) -> type_declaration: ...
     def declared_type(self): ...
 
 def arrange_polygons(polygons): ...