diff --git a/src/dabmodel/model.py b/src/dabmodel/model.py
index 956c87a..5eab716 100644
--- a/src/dabmodel/model.py
+++ b/src/dabmodel/model.py
@@ -298,7 +298,7 @@ class DABFieldInfo:
             self._constraints = constraints
 
     @property
-    def doc(self):
+    def doc(self) -> str:
         """Returns Field's documentation"""
         return self._doc
 
@@ -325,7 +325,7 @@ class DABField(Generic[T_Field]):
         self._source = s
 
     @property
-    def doc(self):
+    def doc(self) -> str:
         """Returns Field's documentation"""
         return self._info.doc
 
@@ -403,10 +403,14 @@ class ModelSpecView:
 
     __slots__ = ("_vals", "_types", "_touched", "_name", "_module")
 
-    def __init__(self, values: dict, types_map: dict[str, type], name, module):
+    def __init__(self, values: dict[str, Any], types_map: dict[str, type], name: str, module: str):
+        self._name: str
+        self._vals: dict[str, Any]
+        self._types: dict[str, type]
+        self._touched: set
+        self._module: str
         object.__setattr__(self, "_vals", dict(values))
         object.__setattr__(self, "_types", types_map)
-        object.__setattr__(self, "_touched", set())
         object.__setattr__(self, "_name", name)
         object.__setattr__(self, "_module", module)
 
@@ -421,16 +425,16 @@ class ModelSpecView:
         return self._module
 
     @__module__.setter
-    def __module__(self, value):
+    def __module__(self, value: str):
         pass
 
-    def __getattr__(self, name):
+    def __getattr__(self, name: str) -> Any:
         """internal proxy getattr"""
         if name not in self._types:
             raise AttributeError(f"Unknown field {name}")
         return self._vals[name]
 
-    def __setattr__(self, name, value):
+    def __setattr__(self, name: str, value: Any):
         """internal proxy setattr"""
         if name not in self._types:
             raise NonExistingField(f"Cannot set unknown field {name}")
@@ -446,7 +450,6 @@ class ModelSpecView:
             raise InvalidFieldValue(f"Field <{name}> value is not of expected type {T}.") from exp
 
         self._vals[name] = value
-        self._touched.add(name)
 
     def export(self) -> dict:
         """exports all proxified values"""
@@ -621,7 +624,7 @@ class BaseMeta(type):
 
         orig_setattr = namespace.get("__setattr__", object.__setattr__)
 
-        def guarded_setattr(self, key, value):
+        def guarded_setattr(self, key: str, value: Any):
             if key.startswith("_"):  # allow private and dunder attrs
                 return orig_setattr(self, key, value)
             # block writes after init if key is readonly