diff --git a/app/db/oper/agenttask.py b/app/db/oper/agenttask.py
index f9ad2fa7b..cfc5a8861 100644
--- a/app/db/oper/agenttask.py
+++ b/app/db/oper/agenttask.py
@@ -4,6 +4,7 @@ from datetime import datetime
 from typing import Optional
 from uuid import uuid4
 
+from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm import Session
 
 from app.db.base import DbOper
@@ -66,6 +67,25 @@ class AgentTaskOper(DbOper):
             return query(self._db)
         return run_sync_transaction(query)
 
+    async def async_get(
+            self,
+            task_id: int,
+            user_id: Optional[str] = None,
+    ) -> Optional[AgentTask]:
+        """通过异步会话查询单个 Agent 定时任务。"""
+        async def query(session: AsyncSession) -> Optional[AgentTask]:
+            """在调用方异步会话中执行与同步入口相同的查询语义。"""
+            result = await session.execute(
+                _get_for_user_statement(
+                    AgentTask,
+                    task_id=task_id,
+                    user_id=user_id,
+                )
+            )
+            return result.scalars().first()
+
+        return await self._execute_async_query(query)
+
     def list(
             self,
             user_id: Optional[str] = None,
diff --git a/app/scheduler.py b/app/scheduler.py
index 1128de57c..2a5b3720e 100644
--- a/app/scheduler.py
+++ b/app/scheduler.py
@@ -1600,7 +1600,7 @@ class Scheduler(ConfigReloadMixin, metaclass=SingletonClass):
                 trigger_source=trigger_source,
             )
         finally:
-            task = AgentTaskOper().get(task_id)
+            task = await AgentTaskOper().async_get(task_id)
             if task and task.trigger_type == "date" and not task.enabled:
                 self.remove_agent_task_job(task_id)
 
diff --git a/docs/refactor/backend-architecture-next-stage.md b/docs/refactor/backend-architecture-next-stage.md
index c15a0783d..f4fd0093b 100644
--- a/docs/refactor/backend-architecture-next-stage.md
+++ b/docs/refactor/backend-architecture-next-stage.md
@@ -19,7 +19,8 @@
 - 启动性能探针会在隔离生命周期中真实创建并释放 TaskRegistry；normal/safe 组件数分别为 `23`/`11`，CI 只读检查使用稳定的宿主模块集合和生命周期组件顺序，不再把 Python/平台模块数量当作硬合同。
 - 官方插件快照覆盖 `plugins.v3`、`plugins.v2` 以及 V3 实际会从 `package.json` 回退加载的 31 个默认实现；`app/plugins/**` 仍只是宿主运行副本，不进入扫描。
 - SDK 快照以各模块显式 `__all__` 为公开合同，能够记录赋值别名；`typing`、`__future__` 等实现期导入不再被误冻结，既有数据库备份门面已补精确导出清单。
-- async 阻塞实际债务已由 fixture 中的 10 项下降到 1 项并固化低水位；剩余项是 Scheduler Agent task 查询，后续阶段迁入异步查询边界后归零。
+- async 阻塞实际债务已由 fixture 中的 10 项归零；Scheduler Agent task 收尾查询已复用
+  `AgentTaskOper.async_get` 的统一 AsyncSession 边界，CI 继续以零债务基线拒绝回退。
 
 本阶段只修复治理信号和事实源，不把基线刷新当作业务重构完成。后台任务所有权、Module Contract V2、typed runtime、durable 副作用和质量规模化仍按下列 P1/P2 顺序推进。
 
diff --git a/tests/fixtures/architecture/async-blocking-baseline.json b/tests/fixtures/architecture/async-blocking-baseline.json
index 4fcc9c251..0967ef424 100644
--- a/tests/fixtures/architecture/async-blocking-baseline.json
+++ b/tests/fixtures/architecture/async-blocking-baseline.json
@@ -1,3 +1 @@
-{
-  "app/scheduler.py:Scheduler.execute_agent_task:AgentTaskOper.get": 1
-}
+{}
diff --git a/tests/test_agent_task_runs.py b/tests/test_agent_task_runs.py
index 3c0aa3e66..eebbb4949 100644
--- a/tests/test_agent_task_runs.py
+++ b/tests/test_agent_task_runs.py
@@ -1,6 +1,8 @@
 import json
 from concurrent.futures import ThreadPoolExecutor
 from threading import Event, Thread, current_thread
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, Mock
 from uuid import uuid4
 
 import pytest
@@ -15,6 +17,7 @@ from app.db.oper.agenttask import AgentTaskOper
 from app.db.models.agenttask import AgentTask
 from app.db.models.agenttaskrun import AgentTaskRun
 from app.db.session import SessionFactory
+from app.scheduler import Scheduler
 
 
 Engine = get_engine()
@@ -153,6 +156,40 @@ def test_agenttaskrun_oper_reuses_explicit_query_session(db, monkeypatch):
     assert oper.list_runs(task.id)
 
 
+@pytest.mark.anyio
+async def test_agenttask_oper_async_get_uses_async_query_boundary() -> None:
+    """异步任务查询应复用统一 AsyncSession 路径并保持 owner 过滤语义。"""
+    task = _add_task("run-async-query")
+
+    assert await AgentTaskOper().async_get(task.id, user_id=task.user_id) is not None
+    assert await AgentTaskOper().async_get(task.id, user_id="another-user") is None
+
+
+@pytest.mark.anyio
+async def test_scheduler_agent_task_cleanup_uses_async_query(monkeypatch) -> None:
+    """async 调度收尾必须等待异步任务查询，不得退回同步 Oper 调用。"""
+    execute = AsyncMock(return_value=(True, "执行完成"))
+    async_get = AsyncMock(
+        return_value=SimpleNamespace(trigger_type="cron", enabled=True)
+    )
+    sync_get = Mock(side_effect=AssertionError("不应调用同步 AgentTaskOper.get"))
+    scheduler = SimpleNamespace(remove_agent_task_job=Mock())
+    monkeypatch.setattr(
+        "app.agent.runtime_loader.get_running_agent_manager",
+        lambda: SimpleNamespace(execute_scheduled_task=execute),
+    )
+    monkeypatch.setattr(AgentTaskOper, "async_get", async_get)
+    monkeypatch.setattr(AgentTaskOper, "get", sync_get)
+
+    result = await Scheduler.execute_agent_task(scheduler, task_id=42)
+
+    assert result == (True, "执行完成")
+    execute.assert_awaited_once_with(42, trigger_source="scheduled")
+    async_get.assert_awaited_once_with(42)
+    sync_get.assert_not_called()
+    scheduler.remove_agent_task_job.assert_not_called()
+
+
 def test_begin_run_rolls_back_task_claim_when_run_insert_fails() -> None:
     """运行记录插入失败时，任务的 running 投影必须随事务回滚。"""
     first_task = _add_task("run-rollback-first")