fix: re-raise output guardrail exceptions in streaming path

- Fix OutputGuardrailTripwireTriggered silently swallowed by bare
  except Exception in run_loop.py streaming path
- Re-raise asyncio.CancelledError for Python 3.9/3.10 compatibility
- Fix SQLiteSession race condition: replace per-call threading.Lock()
  with shared self._file_lock for file-based databases

Author: gn00295120

src/agents/memory/sqlite_session.py

@@ -47,6 +47,7 @@ def __init__(
         self.messages_table = messages_table
         self._local = threading.local()
         self._lock = threading.Lock()
+        self._file_lock = threading.Lock()
 
         # For in-memory databases, we need a shared connection to avoid thread isolation
         # For file databases, we use thread-local connections for better concurrency
@@ -128,7 +129,7 @@ async def get_items(self, limit: int | None = None) -> list[TResponseInputItem]:
 
         def _get_items_sync():
             conn = self._get_connection()
-            with self._lock if self._is_memory_db else threading.Lock():
+            with self._lock if self._is_memory_db else self._file_lock:
                 if session_limit is None:
                     # Fetch all items in chronological order
                     cursor = conn.execute(
@@ -182,7 +183,7 @@ async def add_items(self, items: list[TResponseInputItem]) -> None:
         def _add_items_sync():
             conn = self._get_connection()
 
-            with self._lock if self._is_memory_db else threading.Lock():
+            with self._lock if self._is_memory_db else self._file_lock:
                 # Ensure session exists
                 conn.execute(
                     f"""
@@ -223,7 +224,7 @@ async def pop_item(self) -> TResponseInputItem | None:
 
         def _pop_item_sync():
             conn = self._get_connection()
-            with self._lock if self._is_memory_db else threading.Lock():
+            with self._lock if self._is_memory_db else self._file_lock:
                 # Use DELETE with RETURNING to atomically delete and return the most recent item
                 cursor = conn.execute(
                     f"""
@@ -260,7 +261,7 @@ async def clear_session(self) -> None:
 
         def _clear_session_sync():
             conn = self._get_connection()
-            with self._lock if self._is_memory_db else threading.Lock():
+            with self._lock if self._is_memory_db else self._file_lock:
                 conn.execute(
                     f"DELETE FROM {self.messages_table} WHERE session_id = ?",
                     (self.session_id,),

src/agents/run_internal/run_loop.py

@@ -30,6 +30,7 @@
     InputGuardrailTripwireTriggered,
     MaxTurnsExceeded,
     ModelBehaviorError,
+    OutputGuardrailTripwireTriggered,
     RunErrorDetails,
     UserError,
 )
@@ -344,7 +345,12 @@ async def _run_output_guardrails_for_stream(
 
     try:
         return cast(list[Any], await streamed_result._output_guardrails_task)
+    except OutputGuardrailTripwireTriggered:
+        raise
+    except asyncio.CancelledError:
+        raise
     except Exception:
+        logger.error("Unexpected error in output guardrails", exc_info=True)
         return []