diff --git a/libp2p/pubsub/pubsub.py b/libp2p/pubsub/pubsub.py
index 1614bedc..e00dc945 100644
--- a/libp2p/pubsub/pubsub.py
+++ b/libp2p/pubsub/pubsub.py
@@ -233,7 +233,7 @@ class Pubsub(Service, IPubsub):
             await self.validation_throttler.start(nursery)
             # Keep nursery alive until service stops
             while self.manager.is_running:
-                await trio.sleep(1)
+                await self.manager.wait_finished()
 
     @property
     def my_id(self) -> ID:
diff --git a/libp2p/pubsub/validation_throttler.py b/libp2p/pubsub/validation_throttler.py
index 38b4991c..cea4ce27 100644
--- a/libp2p/pubsub/validation_throttler.py
+++ b/libp2p/pubsub/validation_throttler.py
@@ -1,20 +1,23 @@
 from collections.abc import (
-    Awaitable,
     Callable,
 )
 from dataclasses import dataclass
 from enum import Enum
-import inspect
 import logging
 from typing import (
-    Any,
     NamedTuple,
+    cast,
 )
 
 import trio
 
-from libp2p.custom_types import (
-    ValidatorFn,
+from libp2p.custom_types import AsyncValidatorFn, ValidatorFn
+from libp2p.peer.id import (
+    ID,
+)
+
+from .pb import (
+    rpc_pb2,
 )
 
 logger = logging.getLogger("libp2p.pubsub.validation")
@@ -32,9 +35,8 @@ class ValidationRequest:
     """Request for message validation"""
 
     validators: list["TopicValidator"]
-    # TODO: Use a more specific type for msg_forwarder
-    msg_forwarder: Any  # peer ID
-    msg: Any  # message object
+    msg_forwarder: ID  # peer ID
+    msg: rpc_pb2.Message  # message object
     result_callback: Callable[[ValidationResult, Exception | None], None]
 
 
@@ -109,8 +111,8 @@ class ValidationThrottler:
     async def submit_validation(
         self,
         validators: list[TopicValidator],
-        msg_forwarder: Any,
-        msg: Any,
+        msg_forwarder: ID,
+        msg: rpc_pb2.Message,
         result_callback: Callable[[ValidationResult, Exception | None], None],
     ) -> bool:
         """
@@ -211,7 +213,7 @@ class ValidationThrottler:
         return ValidationResult.ACCEPT
 
     async def _validate_async_validators(
-        self, validators: list[TopicValidator], msg_forwarder: Any, msg: Any
+        self, validators: list[TopicValidator], msg_forwarder: ID, msg: rpc_pb2.Message
     ) -> ValidationResult:
         """Handle async validators with proper throttling"""
         if len(validators) == 1:
@@ -268,7 +270,7 @@ class ValidationThrottler:
         return ValidationResult.IGNORE
 
     async def _validate_single_async_validator(
-        self, validator: TopicValidator, msg_forwarder: Any, msg: Any
+        self, validator: TopicValidator, msg_forwarder: ID, msg: rpc_pb2.Message
     ) -> ValidationResult:
         """Validate with a single async validator"""
         # Apply per-topic throttling
@@ -286,20 +288,14 @@ class ValidationThrottler:
 
         try:
             # Apply timeout if configured
-            result: bool | Awaitable[bool]
+            result: bool
             if validator.timeout:
                 with trio.fail_after(validator.timeout):
-                    func = validator.validator
-                    if inspect.iscoroutinefunction(func):
-                        result = await func(msg_forwarder, msg)
-                    else:
-                        result = func(msg_forwarder, msg)
-            else:
-                func = validator.validator
-                if inspect.iscoroutinefunction(func):
+                    func = cast(AsyncValidatorFn, validator.validator)
                     result = await func(msg_forwarder, msg)
-                else:
-                    result = func(msg_forwarder, msg)
+            else:
+                func = cast(AsyncValidatorFn, validator.validator)
+                result = await func(msg_forwarder, msg)
 
             return ValidationResult.ACCEPT if result else ValidationResult.REJECT