diff --git a/src/google/adk/plugins/context_filter_plugin.py b/src/google/adk/plugins/context_filter_plugin.py
index b778de02ad..5b93a31708 100644
--- a/src/google/adk/plugins/context_filter_plugin.py
+++ b/src/google/adk/plugins/context_filter_plugin.py
@@ -16,11 +16,11 @@
 
 import logging
 from typing import Callable
-from typing import List
 from typing import Optional
 
+from google.genai import types
+
 from ..agents.callback_context import CallbackContext
-from ..events.event import Event
 from ..models.llm_request import LlmRequest
 from ..models.llm_response import LlmResponse
 from .base_plugin import BasePlugin
@@ -34,7 +34,9 @@ class ContextFilterPlugin(BasePlugin):
   def __init__(
       self,
       num_invocations_to_keep: Optional[int] = None,
-      custom_filter: Optional[Callable[[List[Event]], List[Event]]] = None,
+      custom_filter: Optional[
+          Callable[[list[types.Content]], list[types.Content]]
+      ] = None,
       name: str = "context_filter_plugin",
   ):
     """Initializes the context management plugin.