diff --git a/src/hawk/client.py b/src/hawk/client.py
index 4c9b84e..357046e 100644
--- a/src/hawk/client.py
+++ b/src/hawk/client.py
@@ -232,7 +232,7 @@ def delete_session(self, session_id: str) -> None:
         def _do() -> None:
             self._request("DELETE", f"/v1/sessions/{session_id}")
 
-        with_retry_sync(_do, self._retry_config)
+        return with_retry_sync(_do, self._retry_config)
 
     def list_messages(
         self, session_id: str, limit: int = 50, offset: int = 0
@@ -443,7 +443,7 @@ async def delete_session(self, session_id: str) -> None:
         async def _do() -> None:
             await self._request("DELETE", f"/v1/sessions/{session_id}")
 
-        await with_retry(_do, self._retry_config)
+        return await with_retry(_do, self._retry_config)
 
     async def list_messages(
         self, session_id: str, limit: int = 50, offset: int = 0
diff --git a/src/hawk/retry.py b/src/hawk/retry.py
index bbd3cf8..be2e9ec 100644
--- a/src/hawk/retry.py
+++ b/src/hawk/retry.py
@@ -4,6 +4,7 @@
 
 import asyncio
 import random
+import time
 from dataclasses import dataclass, field
 from typing import TYPE_CHECKING, Callable, TypeVar
 
@@ -113,8 +114,6 @@ def with_retry_sync(
     Raises:
         The last exception if all retries are exhausted.
     """
-    import time
-
     if config is None:
         config = DEFAULT_RETRY_CONFIG