diff --git a/backend/server/routers/scheduler_router.py b/backend/server/routers/scheduler_router.py
index 63759334..64ffcb46 100644
--- a/backend/server/routers/scheduler_router.py
+++ b/backend/server/routers/scheduler_router.py
@@ -13,7 +13,7 @@ from __future__ import annotations
 
 from typing import Any
 
-from fastapi import APIRouter, Depends, Query
+from fastapi import APIRouter, Depends, Header, Query
 from pydantic import BaseModel, ConfigDict, Field
 from sqlalchemy.ext.asyncio import AsyncSession
 from yuxi.scheduler.infrastructure.container import create_scheduler_service
@@ -149,12 +149,22 @@ async def list_tasks(
 @scheduler_router.post("/tasks", response_model=dict)
 async def create_task(
     body: CreateTaskRequest,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
     """创建定时任务（FR-ST-01 / FR-ST-05）。"""
     service = create_scheduler_service(db)
-    input_dto = CreateTaskInput(**body.model_dump(), created_by=current_user.uid)
+    input_dto = CreateTaskInput(
+        **body.model_dump(),
+        created_by=current_user.uid,
+        idempotency_key=idempotency_key,
+    )
     output = await service.create_task(input_dto)
     return {"success": True, "data": output.model_dump()}
 
@@ -231,6 +241,12 @@ async def get_task(
 async def update_task(
     task_id: str,
     body: UpdateTaskRequest,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
@@ -239,6 +255,7 @@ async def update_task(
     input_dto = UpdateTaskInput(
         task_id=task_id,
         updated_by=current_user.uid,
+        idempotency_key=idempotency_key,
         **body.model_dump(exclude_unset=True),
     )
     output = await service.update_task(input_dto)
@@ -248,12 +265,22 @@ async def update_task(
 @scheduler_router.delete("/tasks/{task_id}", response_model=dict)
 async def delete_task(
     task_id: str,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
     """删除定时任务（软删除，FR-ST-05）。"""
     service = create_scheduler_service(db)
-    input_dto = DeleteTaskInput(task_id=task_id, updated_by=current_user.uid)
+    input_dto = DeleteTaskInput(
+        task_id=task_id,
+        updated_by=current_user.uid,
+        idempotency_key=idempotency_key,
+    )
     await service.delete_task(input_dto)
     return {"success": True, "data": {"task_id": task_id, "status": "deleted"}}
 
@@ -261,12 +288,22 @@ async def delete_task(
 @scheduler_router.post("/tasks/{task_id}/pause", response_model=dict)
 async def pause_task(
     task_id: str,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
     """暂停任务（FR-ST-05）。"""
     service = create_scheduler_service(db)
-    input_dto = PauseTaskInput(task_id=task_id, updated_by=current_user.uid)
+    input_dto = PauseTaskInput(
+        task_id=task_id,
+        updated_by=current_user.uid,
+        idempotency_key=idempotency_key,
+    )
     output = await service.pause_task(input_dto)
     return {"success": True, "data": output.model_dump()}
 
@@ -274,6 +311,12 @@ async def pause_task(
 @scheduler_router.post("/tasks/{task_id}/resume", response_model=dict)
 async def resume_task(
     task_id: str,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
@@ -282,7 +325,11 @@ async def resume_task(
     ``paused`` -> ``active`` / ``dead_letter`` -> ``active``。
     """
     service = create_scheduler_service(db)
-    input_dto = ResumeTaskInput(task_id=task_id, updated_by=current_user.uid)
+    input_dto = ResumeTaskInput(
+        task_id=task_id,
+        updated_by=current_user.uid,
+        idempotency_key=idempotency_key,
+    )
     output = await service.resume_task(input_dto)
     return {"success": True, "data": output.model_dump()}
 
@@ -291,6 +338,12 @@ async def resume_task(
 async def trigger_task(
     task_id: str,
     body: TriggerTaskRequest | None = None,
+    idempotency_key: str | None = Header(
+        default=None,
+        alias="Idempotency-Key",
+        max_length=128,
+        description="幂等键，启用后重复请求回放缓存响应",
+    ),
     db: AsyncSession = Depends(get_db),
     current_user: User = Depends(get_admin_user),
 ) -> dict[str, Any]:
@@ -298,6 +351,7 @@ async def trigger_task(
 
     生成 ``run_id`` 后入队 ARQ 执行，不影响下一次自动执行。
     可通过 body 传入 payload 覆盖任务定义中的 payload，None 时使用任务原 payload。
+    触发人 ``current_user.uid`` 透传到 worker 写入 ``run_log.created_by`` 审计字段。
     """
     arq_pool = await get_arq_pool()
     service = create_scheduler_service(db, arq_pool=arq_pool)
@@ -306,6 +360,8 @@ async def trigger_task(
         task_id=task_id,
         triggered_by="manual",
         payload=payload,
+        operator=current_user.uid,
+        idempotency_key=idempotency_key,
     )
     output = await service.trigger_task(input_dto)
     return {"success": True, "data": output.model_dump()}