diff --git a/durabletask-azuremanaged/durabletask/azuremanaged/client.py b/durabletask-azuremanaged/durabletask/azuremanaged/client.py
index f641eae..1d8cecd 100644
--- a/durabletask-azuremanaged/durabletask/azuremanaged/client.py
+++ b/durabletask-azuremanaged/durabletask/azuremanaged/client.py
@@ -2,6 +2,7 @@
 # Licensed under the MIT License.
 
 from azure.core.credentials import TokenCredential
+from typing import Optional
 
 from durabletask.azuremanaged.internal.durabletask_grpc_interceptor import \
     DTSDefaultClientInterceptorImpl
@@ -13,7 +14,7 @@ class DurableTaskSchedulerClient(TaskHubGrpcClient):
     def __init__(self, *,
                  host_address: str,
                  taskhub: str,
-                 token_credential: TokenCredential,
+                 token_credential: Optional[TokenCredential],
                  secure_channel: bool = True):
 
         if not taskhub:
diff --git a/durabletask-azuremanaged/durabletask/azuremanaged/internal/durabletask_grpc_interceptor.py b/durabletask-azuremanaged/durabletask/azuremanaged/internal/durabletask_grpc_interceptor.py
index a23cac9..077905e 100644
--- a/durabletask-azuremanaged/durabletask/azuremanaged/internal/durabletask_grpc_interceptor.py
+++ b/durabletask-azuremanaged/durabletask/azuremanaged/internal/durabletask_grpc_interceptor.py
@@ -2,6 +2,8 @@
 # Licensed under the MIT License.
 
 import grpc
+from typing import Optional
+
 from azure.core.credentials import TokenCredential
 
 from durabletask.azuremanaged.internal.access_token_manager import \
@@ -15,7 +17,7 @@ class DTSDefaultClientInterceptorImpl (DefaultClientInterceptorImpl):
     StreamUnaryClientInterceptor and StreamStreamClientInterceptor from grpc to add an
     interceptor to add additional headers to all calls as needed."""
 
-    def __init__(self, token_credential: TokenCredential, taskhub_name: str):
+    def __init__(self, token_credential: Optional[TokenCredential], taskhub_name: str):
         self._metadata = [("taskhub", taskhub_name)]
         super().__init__(self._metadata)
 
diff --git a/durabletask-azuremanaged/durabletask/azuremanaged/worker.py b/durabletask-azuremanaged/durabletask/azuremanaged/worker.py
index d10c2f7..8bdff3d 100644
--- a/durabletask-azuremanaged/durabletask/azuremanaged/worker.py
+++ b/durabletask-azuremanaged/durabletask/azuremanaged/worker.py
@@ -2,6 +2,7 @@
 # Licensed under the MIT License.
 
 from azure.core.credentials import TokenCredential
+from typing import Optional
 
 from durabletask.azuremanaged.internal.durabletask_grpc_interceptor import \
     DTSDefaultClientInterceptorImpl
@@ -13,7 +14,7 @@ class DurableTaskSchedulerWorker(TaskHubGrpcWorker):
     def __init__(self, *,
                  host_address: str,
                  taskhub: str,
-                 token_credential: TokenCredential,
+                 token_credential: Optional[TokenCredential],
                  secure_channel: bool = True):
 
         if not taskhub: