From 58e7501cc5b7da8ecb9dd6b84cdf1f55cee8dfc1 Mon Sep 17 00:00:00 2001
From: Tsuyoshi Ushio <tsushi@microsoft.com>
Date: Thu, 3 Sep 2026 19:40:03 -0700
Subject: [PATCH] Preserve activity tags across retries

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---
 CHANGELOG.md                                  |  5 ++
 durabletask/worker.py                         |  3 +
 .../test_orchestration_executor.py            | 59 +++++++++++++++++++
 3 files changed, 67 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b5f64649..3b9ae6af 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,11 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
 
+FIXED
+
+- Activity tags, including `durabletask.displayName`, are now preserved across
+retry attempts.
+
 ## v1.10.0
 
 ADDED
diff --git a/durabletask/worker.py b/durabletask/worker.py
index bc6aba8f..f4f31a32 100644
--- a/durabletask/worker.py
+++ b/durabletask/worker.py
@@ -2590,14 +2590,17 @@ def _cancel_timer() -> None:
                         if not timer_task._retryable_parent._is_sub_orch:  # pyright: ignore[reportPrivateUsage]
                             cur_task = activity_action.scheduleTask
                             instance_id = None
+                            tags = dict(cur_task.tags)
                         else:
                             cur_task = activity_action.createSubOrchestration
                             instance_id = cur_task.instanceId
+                            tags = None
                         ctx.call_activity_function_helper(
                             id=activity_action.id,
                             activity_function=cur_task.name,
                             input=cur_task.input.value,
                             retry_policy=timer_task._retryable_parent._retry_policy,  # pyright: ignore[reportPrivateUsage]
+                            tags=tags,
                             is_sub_orch=timer_task._retryable_parent._is_sub_orch,  # pyright: ignore[reportPrivateUsage]
                             instance_id=instance_id,
                             fn_task=timer_task._retryable_parent,  # pyright: ignore[reportPrivateUsage]
diff --git a/tests/durabletask/test_orchestration_executor.py b/tests/durabletask/test_orchestration_executor.py
index 9bef05a8..a7064145 100644
--- a/tests/durabletask/test_orchestration_executor.py
+++ b/tests/durabletask/test_orchestration_executor.py
@@ -933,6 +933,65 @@ def orchestrator(ctx: task.OrchestrationContext, orchestrator_input):
     assert actions[-1].id == 7
 
 
+def test_activity_retry_preserves_tags():
+    """Activity tags are preserved on every retry-generated schedule action."""
+
+    def dummy_activity(ctx, _):
+        raise ValueError("Kah-BOOOOM!!!")
+
+    tags = {
+        "durabletask.displayName": "reserve_inventory",
+        "custom": "value",
+    }
+
+    def orchestrator(ctx: task.OrchestrationContext, orchestrator_input):
+        return (yield ctx.call_activity(
+            dummy_activity,
+            retry_policy=task.RetryPolicy(
+                first_retry_interval=timedelta(seconds=1),
+                max_number_of_attempts=3,
+            ),
+            input=orchestrator_input,
+            tags=tags,
+        ))
+
+    registry = worker._Registry()
+    name = registry.add_orchestrator(orchestrator)
+    current_timestamp = datetime.utcnow()
+    old_events = [
+        helpers.new_orchestrator_started_event(timestamp=current_timestamp),
+        helpers.new_execution_started_event(name, TEST_INSTANCE_ID, encoded_input=None),
+        helpers.new_task_scheduled_event(1, task.get_name(dummy_activity)),
+    ]
+
+    for _ in range(2):
+        failed_events = [
+            helpers.new_orchestrator_started_event(timestamp=current_timestamp),
+            helpers.new_task_failed_event(1, ValueError("Kah-BOOOOM!!!")),
+        ]
+        executor = worker._OrchestrationExecutor(registry, TEST_LOGGER, JsonDataConverter())
+        result = executor.execute(TEST_INSTANCE_ID, old_events, failed_events)
+        timer_action = next(action for action in result.actions if action.HasField("createTimer"))
+
+        old_events += failed_events
+        current_timestamp = timer_action.createTimer.fireAt.ToDatetime()
+        timer_events = [
+            helpers.new_orchestrator_started_event(current_timestamp),
+            helpers.new_timer_fired_event(timer_action.id, current_timestamp),
+        ]
+        executor = worker._OrchestrationExecutor(registry, TEST_LOGGER, JsonDataConverter())
+        result = executor.execute(TEST_INSTANCE_ID, old_events, timer_events)
+        retry_actions = [
+            action.scheduleTask
+            for action in result.actions
+            if action.HasField("scheduleTask")
+        ]
+
+        assert len(retry_actions) == 1
+        assert dict(retry_actions[0].tags) == tags
+        old_events += timer_events
+
+
 def test_activity_retry_without_max_retry_interval():
     """Tests that retry logic works correctly when max_retry_interval is not set.