diff --git a/packages/toolbox-adk/pyproject.toml b/packages/toolbox-adk/pyproject.toml
index f648ea95a..794b76a2c 100644
--- a/packages/toolbox-adk/pyproject.toml
+++ b/packages/toolbox-adk/pyproject.toml
@@ -20,9 +20,9 @@ classifiers = [
 requires-python = ">=3.10"
 dependencies = [
     "toolbox-core==0.6.0",
-    "google-auth>=2.43.0,<3.0.0",
+    "google-auth>=2.47.0,<3.0.0",
     "google-auth-oauthlib>=1.2.0,<2.0.0",
-    "google-adk>=1.20.0,<3.0.0", 
+    "google-adk>=1.26.0,<3.0.0", 
     "typing-extensions>=4.0.0"
 ]
 
diff --git a/packages/toolbox-adk/requirements.txt b/packages/toolbox-adk/requirements.txt
index ef58745cd..91c59ae87 100644
--- a/packages/toolbox-adk/requirements.txt
+++ b/packages/toolbox-adk/requirements.txt
@@ -1,6 +1,6 @@
 -e ../toolbox-core
-google-adk==1.20.0
-google-auth==2.45.0
+google-adk==1.27.2
+google-auth==2.47.0
 google-auth-oauthlib==1.2.1
 typing-extensions==4.14.1
 opentelemetry-exporter-otlp-proto-http==1.37.0
diff --git a/packages/toolbox-adk/src/toolbox_adk/tool.py b/packages/toolbox-adk/src/toolbox_adk/tool.py
index 4e9e35279..db41f81b9 100644
--- a/packages/toolbox-adk/src/toolbox_adk/tool.py
+++ b/packages/toolbox-adk/src/toolbox_adk/tool.py
@@ -16,8 +16,6 @@
 import logging
 from typing import Any, Awaitable, Callable, Dict, Mapping, Optional
 
-import google.adk.auth.exchanger.oauth2_credential_exchanger as oauth2_credential_exchanger
-import google.adk.auth.oauth2_credential_util as oauth2_credential_util
 import toolbox_core
 from fastapi.openapi.models import (
     OAuth2,
@@ -40,26 +38,6 @@
 from .client import USER_TOKEN_CONTEXT_VAR
 from .credentials import CredentialConfig, CredentialType
 
-# --- Monkey Patch ADK OAuth2 Exchange to Retain ID Tokens ---
-# Google's ID Token is required by MCP Toolbox but ADK's `update_credential_with_tokens` natively drops the `id_token`.
-# TODO(id_token): Remove this monkey patch once the PR https://github.com/google/adk-python/pull/4402 is merged.
-_orig_update_cred = oauth2_credential_util.update_credential_with_tokens
-
-
-def _patched_update_credential_with_tokens(auth_credential, tokens):
-    _orig_update_cred(auth_credential, tokens)
-    if tokens and "id_token" in tokens and auth_credential and auth_credential.oauth2:
-        setattr(auth_credential.oauth2, "id_token", tokens["id_token"])
-
-
-oauth2_credential_util.update_credential_with_tokens = (
-    _patched_update_credential_with_tokens
-)
-oauth2_credential_exchanger.update_credential_with_tokens = (
-    _patched_update_credential_with_tokens
-)
-# -------------------------------------------------------------
-
 
 class ToolboxTool(BaseTool):
     """
@@ -256,15 +234,9 @@ async def run_async(
                                 not hasattr(self._core_tool, "_auth_token_getters")
                                 or s not in self._core_tool._auth_token_getters
                             ):
-                                # TODO(id_token): Uncomment this line and remove the `getattr` fallback below once PR https://github.com/google/adk-python/pull/4402 is merged.
-                                # self._core_tool = self._core_tool.add_auth_token_getter(s, lambda t=creds.oauth2.id_token or creds.oauth2.access_token: t)
                                 self._core_tool = self._core_tool.add_auth_token_getter(
                                     s,
-                                    lambda t=getattr(
-                                        creds.oauth2,
-                                        "id_token",
-                                        creds.oauth2.access_token,
-                                    ): t,
+                                    lambda t=creds.oauth2.id_token or creds.oauth2.access_token: t,
                                 )
                         # Once we use it from get_auth_response, save it to the auth service for future use
                         try: