fix(tasks): preserve task_metadata in combined update and forward merge_params by name (#336)

Author: declan-scale

agentex/src/api/routes/tasks.py

@@ -214,7 +214,9 @@ async def update_task_by_name(
     task_use_case: DTaskUseCase,
 ) -> Task:
     updated_task_entity = await task_use_case.update_mutable_fields_on_task(
-        name=task_name, task_metadata=request.task_metadata
+        name=task_name,
+        task_metadata=request.task_metadata,
+        merge_params=request.merge_params,
     )
     return Task.model_validate(updated_task_entity)
 

agentex/src/domain/use_cases/tasks_use_case.py

@@ -113,13 +113,12 @@ async def update_mutable_fields_on_task(
         if task_metadata is None and merge_params is None:
             return task_entity
 
-        if task_metadata is not None:
-            task_entity.task_metadata = task_metadata
-
         # `merge_params` is a separate atomic JSONB shallow-merge so concurrent
         # callers don't overwrite each other's fields (vs reading→mutating→writing
-        # the whole params dict on task_entity). Falls through to a normal save
-        # only when task_metadata also changed.
+        # the whole params dict on task_entity). Run it first so the refreshed
+        # entity it returns becomes the base we apply `task_metadata` on top of;
+        # otherwise the `task_entity = merged` reassignment would discard an
+        # in-memory metadata change made before the merge.
         if merge_params:
             merged = await self.task_service.merge_task_params(
                 task_entity.id, merge_params
@@ -128,6 +127,7 @@ async def update_mutable_fields_on_task(
                 task_entity = merged
 
         if task_metadata is not None:
+            task_entity.task_metadata = task_metadata
             task_entity = await self.task_service.update_task(task=task_entity)
 
         return task_entity

agentex/tests/integration/api/tasks/test_tasks_api.py

@@ -911,6 +911,87 @@ async def test_update_task_by_name_endpoint_success(
         assert response_data["task_metadata"]["configuration"]["version"] == "2.0.0"
         assert response_data["task_metadata"]["metrics"]["complexity_score"] == 75
 
+    async def test_update_task_by_name_forwards_merge_params(
+        self, isolated_client, isolated_repositories
+    ):
+        """PUT /tasks/name/{task_name} must forward merge_params, not drop it."""
+        # Given - a task with existing params
+        agent_repo = isolated_repositories["agent_repository"]
+        agent = AgentEntity(
+            id=orm_id(),
+            name="merge-params-by-name-agent",
+            description="Agent for merge_params by name testing",
+            acp_url="http://test-acp:8000",
+            acp_type=ACPType.SYNC,
+        )
+        await agent_repo.create(agent)
+
+        task_repo = isolated_repositories["task_repository"]
+        task = TaskEntity(
+            id=orm_id(),
+            name="task-for-merge-params-by-name",
+            status=TaskStatus.RUNNING,
+            status_reason="Test task for merge_params by name endpoint",
+            params={"model": "gpt-4", "temperature": 0.2},
+        )
+        created_task = await task_repo.create(agent_id=agent.id, task=task)
+
+        # When - update by name supplying only merge_params
+        update_payload = {"merge_params": {"temperature": 0.9, "max_tokens": 1024}}
+        response = await isolated_client.put(
+            f"/tasks/name/{created_task.name}", json=update_payload
+        )
+
+        # Then - the patch is shallow-merged into the existing params
+        assert response.status_code == 200
+        response_data = response.json()
+        assert response_data["params"] == {
+            "model": "gpt-4",
+            "temperature": 0.9,
+            "max_tokens": 1024,
+        }
+
+    async def test_update_task_metadata_and_merge_params_together(
+        self, isolated_client, isolated_repositories
+    ):
+        """Supplying both task_metadata and merge_params must persist both."""
+        # Given - a task with existing params and metadata
+        agent_repo = isolated_repositories["agent_repository"]
+        agent = AgentEntity(
+            id=orm_id(),
+            name="merge-params-and-metadata-agent",
+            description="Agent for combined update testing",
+            acp_url="http://test-acp:8000",
+            acp_type=ACPType.SYNC,
+        )
+        await agent_repo.create(agent)
+
+        task_repo = isolated_repositories["task_repository"]
+        task = TaskEntity(
+            id=orm_id(),
+            name="task-for-combined-update",
+            status=TaskStatus.RUNNING,
+            status_reason="Test task for combined update endpoint",
+            params={"model": "gpt-4"},
+            task_metadata={"initial": "metadata"},
+        )
+        created_task = await task_repo.create(agent_id=agent.id, task=task)
+
+        # When - update by id supplying both fields at once
+        update_payload = {
+            "task_metadata": {"stage": "tuned"},
+            "merge_params": {"temperature": 0.7},
+        }
+        response = await isolated_client.put(
+            f"/tasks/{created_task.id}", json=update_payload
+        )
+
+        # Then - neither field is silently discarded
+        assert response.status_code == 200
+        response_data = response.json()
+        assert response_data["task_metadata"] == {"stage": "tuned"}
+        assert response_data["params"] == {"model": "gpt-4", "temperature": 0.7}
+
     async def test_list_tasks_includes_task_metadata_field(
         self, isolated_client, isolated_repositories
     ):

agentex/tests/unit/use_cases/test_tasks_use_case.py

@@ -432,6 +432,33 @@ async def test_update_metadata_by_name(
         # Then
         assert updated.task_metadata == {"via": "name"}
 
+    async def test_update_metadata_and_merge_params_both_persist(
+        self, tasks_use_case, task_service, agent_repository, sample_agent
+    ):
+        """Supplying both task_metadata and merge_params must persist both fields.
+
+        Regression: the merge previously reassigned task_entity to the merged
+        result, discarding the in-memory task_metadata before the final write.
+        """
+        # Given
+        await create_or_get_agent(agent_repository, sample_agent)
+        task = await task_service.create_task(
+            agent=sample_agent,
+            task_name="combined-update-test",
+            task_params={"model": "gpt-4"},
+        )
+
+        # When
+        updated = await tasks_use_case.update_mutable_fields_on_task(
+            id=task.id,
+            task_metadata={"stage": "tuned"},
+            merge_params={"temperature": 0.7},
+        )
+
+        # Then
+        assert updated.task_metadata == {"stage": "tuned"}
+        assert updated.params == {"model": "gpt-4", "temperature": 0.7}
+
     async def test_update_metadata_on_deleted_task_raises(
         self, tasks_use_case, task_service, agent_repository, sample_agent
     ):