diff --git a/packages/exchange/src/exchange/observers/__init__.py b/packages/exchange/src/exchange/observers/__init__.py
index deb917a0..fd70ae86 100644
--- a/packages/exchange/src/exchange/observers/__init__.py
+++ b/packages/exchange/src/exchange/observers/__init__.py
@@ -1,16 +1,20 @@
-from typing import Callable
 from functools import wraps
+from typing import Callable
 
 from exchange.observers.base import ObserverManager
 
-def observe_wrapper(*args, **kwargs) -> Callable:
+
+def observe_wrapper(*args, **kwargs) -> Callable:  # noqa: ANN002, ANN003
     """Decorator to wrap a function with all registered observer plugins, dynamically fetched."""
-    def wrapper(func):
+
+    def wrapper(func: Callable) -> Callable:
         @wraps(func)
-        def dynamic_wrapped(*func_args, **func_kwargs):
+        def dynamic_wrapped(*func_args, **func_kwargs) -> Callable:  # noqa: ANN002, ANN003
             wrapped = func
             for observer in ObserverManager.get_instance()._observers:
                 wrapped = observer.observe_wrapper(*args, **kwargs)(wrapped)
             return wrapped(*func_args, **func_kwargs)
+
         return dynamic_wrapped
-    return wrapper
\ No newline at end of file
+
+    return wrapper
diff --git a/packages/exchange/src/exchange/observers/base.py b/packages/exchange/src/exchange/observers/base.py
index f987b5b9..5adfb417 100644
--- a/packages/exchange/src/exchange/observers/base.py
+++ b/packages/exchange/src/exchange/observers/base.py
@@ -1,5 +1,6 @@
 from abc import ABC, abstractmethod
-from typing import Callable
+from typing import Callable, Type
+
 
 class Observer(ABC):
     @abstractmethod
@@ -7,19 +8,20 @@ def initialize(self) -> None:
         pass
 
     @abstractmethod
-    def observe_wrapper(*args, **kwargs) -> Callable:
+    def observe_wrapper(*args, **kwargs) -> Callable:  # noqa: ANN002, ANN003
         pass
 
     @abstractmethod
     def finalize(self) -> None:
         pass
 
+
 class ObserverManager:
     _instance = None
     _observers: list[Observer] = []
 
     @classmethod
-    def get_instance(cls):
+    def get_instance(cls: Type["ObserverManager"]) -> "ObserverManager":
         if cls._instance is None:
             cls._instance = cls()
         return cls._instance
diff --git a/packages/exchange/src/exchange/observers/langfuse.py b/packages/exchange/src/exchange/observers/langfuse.py
index 90119268..f87d480e 100644
--- a/packages/exchange/src/exchange/observers/langfuse.py
+++ b/packages/exchange/src/exchange/observers/langfuse.py
@@ -67,12 +67,12 @@ def initialize_with_disabled_tracing(self) -> None:
         langfuse_context.configure(enabled=False)
         self.tracing = False
 
-    def observe_wrapper(self, *args, **kwargs) -> Callable:
+    def observe_wrapper(self, *args, **kwargs) -> Callable:  # noqa: ANN002, ANN003
         def _wrapper(fn: Callable) -> Callable:
             if self.tracing and auth_check():
 
                 @wraps(fn)
-                def wrapped_fn(*fargs, **fkwargs) -> Callable:
+                def wrapped_fn(*fargs, **fkwargs) -> Callable:  # noqa: ANN002, ANN003
                     # group all traces under the same session
                     if fn.__name__ == "reply":
                         langfuse_context.update_current_trace(session_id=fargs[0].name)