diff --git a/backend/app/api/screener.py b/backend/app/api/screener.py
index d35faef..3023d20 100644
--- a/backend/app/api/screener.py
+++ b/backend/app/api/screener.py
@@ -199,8 +199,12 @@ def strategies(request: Request):
                 desc = (overrides.get("description") or meta.get("description", "")) if overrides else meta.get("description", "")
                 presets.append({"id": sid, "name": name, "description": desc, "source": meta.get("source", "custom")})
                 seen_ids.add(sid)
+        # 暴露加载失败的策略,让前端可见(避免"策略静默消失"误判为正常)
+        load_errors = engine.load_errors() if engine else []
+    else:
+        load_errors = []
 
-    return {"presets": presets}
+    return {"presets": presets, "load_errors": load_errors}
 
 
 @router.post("/run")
diff --git a/backend/app/api/strategy.py b/backend/app/api/strategy.py
index b355209..9497881 100644
--- a/backend/app/api/strategy.py
+++ b/backend/app/api/strategy.py
@@ -5,6 +5,7 @@
 from __future__ import annotations
 
 import math
+import re
 from dataclasses import asdict
 from datetime import date
 from pathlib import Path
@@ -377,7 +378,16 @@ async def ai_save(req: AISaveRequest, request: Request):
     data_dir = _data_dir(request)
     out_dir = data_dir / "strategies" / "ai"
     out_dir.mkdir(parents=True, exist_ok=True)
-    path = out_dir / f"{req.strategy_id}.py"
+    # 防 path traversal：strategy_id 仅允许字母/数字/下划线/短横线。
+    # 安全性由字符白名单保证(杜绝 / \ .. 等路径分隔/穿越符),文件落点已被
+    # out_dir 锁死在 data/strategies/ai/。前缀只影响 source 标记,允许
+    # ai_ 与 custom_,以兼容「AI 修改 custom 策略」流程(Screener.tsx onAiModify)。
+    sid = req.strategy_id or ""
+    if not re.fullmatch(r"[A-Za-z0-9_-]+", sid):
+        raise HTTPException(status_code=400, detail="strategy_id 仅允许字母、数字、下划线、短横线")
+    if not (sid.startswith("ai_") or sid.startswith("custom_")):
+        raise HTTPException(status_code=400, detail="策略 ID 必须以 ai_ 或 custom_ 开头")
+    path = out_dir / f"{sid}.py"
     previous_code = path.read_text(encoding="utf-8") if path.exists() else None
     path.write_text(req.code, encoding="utf-8")
 
diff --git a/backend/app/strategy/ai_generator.py b/backend/app/strategy/ai_generator.py
index 4db6a5e..a76e6a8 100644
--- a/backend/app/strategy/ai_generator.py
+++ b/backend/app/strategy/ai_generator.py
@@ -18,9 +18,11 @@ GUIDE_PATH = Path(__file__).resolve().parent.parent.parent.parent / "docs" / "st
 
 _SYSTEM_PREFIX = """你是A股量化策略设计专家。根据用户描述的需求，参考下方的《策略开发指南》生成一个完整的策略Python文件。
 
-核心约束:
-- 只创建这一个 .py 文件，不要修改任何现有文件，不要跨文件引用
-- 只 import polars as pl，不 import 其他模块
+文件与范围铁律（不可违反）:
+1. 只创建这一个策略文件：只生成一个 .py 文件，绝不创建多文件、不拆分模块、不跨文件引用
+2. 绝不触碰项目源码：不要写任何会修改 backend/、docs/、frontend/ 等现有文件的代码；不要 import os/sys/pathlib 等文件系统模块
+3. 不得放入内置策略目录：AI 生成的策略只属于 data/strategies/ai/，文件名/ID 用 ai_ 前缀；内置目录 backend/app/strategy/builtin/ 由项目维护，AI 不得染指
+4. 只 import polars as pl，不 import 其他模块
 
 要求:
 1. 用户可能调整的策略阈值通过 META["params"] 暴露；公式常数、固定窗口边界、布尔开关不必强行参数化
diff --git a/backend/app/strategy/engine.py b/backend/app/strategy/engine.py
index 67ef2ad..1f27e62 100644
--- a/backend/app/strategy/engine.py
+++ b/backend/app/strategy/engine.py
@@ -80,6 +80,7 @@ class StrategyEngine:
         self._loader = enriched_loader
         self._history_loader = enriched_history_loader
         self._strategies: dict[str, StrategyDef] = {}
+        self._load_errors: list[dict] = []  # 加载失败的策略 [{file, error}]
         self._strategy_dirs = strategy_dirs or []
         self._load_all()
 
@@ -89,6 +90,7 @@ class StrategyEngine:
 
     def _load_all(self) -> None:
         self._strategies.clear()
+        self._load_errors = []
         for d in self._strategy_dirs:
             if not d.exists():
                 continue
@@ -100,7 +102,13 @@ class StrategyEngine:
                     self._strategies[s.meta["id"]] = s
                     logger.debug("loaded strategy: %s (%s)", s.meta["id"], s.source)
                 except Exception as e:
+                    # 不再静默吞掉: 记录失败项, 供前端可见(避免"策略静默消失"误判)。
                     logger.warning("load strategy %s failed: %s", f.name, e)
+                    self._load_errors.append({"file": f.name, "error": str(e)})
+
+    def load_errors(self) -> list[dict]:
+        """返回最近一次 _load_all 中加载失败的策略 [{file, error}]。"""
+        return list(self._load_errors)
 
     @staticmethod
     def _load_file(path: Path) -> StrategyDef:
diff --git a/frontend/src/components/screener/StrategySettingsDialog.tsx b/frontend/src/components/screener/StrategySettingsDialog.tsx
index f4eb336..24b235c 100644
--- a/frontend/src/components/screener/StrategySettingsDialog.tsx
+++ b/frontend/src/components/screener/StrategySettingsDialog.tsx
@@ -217,6 +217,7 @@ export function StrategySettingsDialog({ strategyId, onClose, onSaved, onAiModif
   const [editingScoring, setEditingScoring] = useState(false)
   const [deleting, setDeleting] = useState(false)
   const [showDeleteConfirm, setShowDeleteConfirm] = useState(false)
+  const [deleteError, setDeleteError] = useState('')
 
   // 辅助：更新 basicFilter 某个 key
   const setBF = useCallback((key: string, value: any) => {
@@ -303,12 +304,16 @@ export function StrategySettingsDialog({ strategyId, onClose, onSaved, onAiModif
   const handleDelete = async () => {
     if (!strategyId) return
     setDeleting(true)
+    setDeleteError('')
     try {
       await api.strategyDelete(strategyId)
       onDeleted?.()
       onClose()
-    } catch { /* ignore */ }
-    finally { setDeleting(false); setShowDeleteConfirm(false) }
+      setShowDeleteConfirm(false)
+    } catch (e: any) {
+      // request() 已弹 toast, 这里再在确认弹窗内显式提示, 并保持弹窗打开让用户知晓删除失败。
+      setDeleteError(String(e?.message ?? '删除失败,请重试'))
+    } finally { setDeleting(false) }
   }
 
   if (!strategyId) return null
@@ -546,7 +551,7 @@ export function StrategySettingsDialog({ strategyId, onClose, onSaved, onAiModif
                 <RotateCcw className="h-3.5 w-3.5" />{resetting ? '重置中…' : '重置默认'}
               </button>
               {(detail?.source === 'ai' || detail?.source === 'custom') && (
-                <button onClick={() => setShowDeleteConfirm(true)}
+                <button onClick={() => { setDeleteError(''); setShowDeleteConfirm(true) }}
                   className="text-[10px] text-muted/40 hover:text-danger transition-colors">删除策略</button>
               )}
             </div>
@@ -591,6 +596,11 @@ export function StrategySettingsDialog({ strategyId, onClose, onSaved, onAiModif
               <div className="text-[11px] text-danger/70 bg-danger/[0.04] rounded-lg px-3 py-2 border border-danger/10">
                 删除后无法恢复，策略文件、配置和关联数据将被永久清除。
               </div>
+              {deleteError && (
+                <div className="text-[11px] text-danger bg-danger/10 rounded-lg px-3 py-2 border border-danger/20">
+                  {deleteError}
+                </div>
+              )}
               <div className="flex gap-2 pt-2">
                 <button onClick={() => setShowDeleteConfirm(false)}
                   className="flex-1 h-8 rounded-lg border border-border text-xs text-secondary hover:text-foreground">取消</button>
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index 43c7b16..b3a406e 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -242,6 +242,11 @@ export interface ScreenerStrategy {
   source?: string
 }
 
+export interface StrategyLoadError {
+  file: string
+  error: string
+}
+
 export interface ScreenerResult {
   as_of: string
   strategy: string | null
@@ -1080,7 +1085,7 @@ export const api = {
         : '/api/watchlist/enriched',
     ),
 
-  screenerStrategies: () => request<{ presets: ScreenerStrategy[] }>('/api/screener/strategies'),
+  screenerStrategies: () => request<{ presets: ScreenerStrategy[]; load_errors?: StrategyLoadError[] }>('/api/screener/strategies'),
   screenerRunPreset: (strategy_id: string, pool?: string[], asOf?: string, extColumns?: string) =>
     request<ScreenerResult>('/api/screener/run_preset', {
       method: 'POST',
diff --git a/frontend/src/pages/Screener.tsx b/frontend/src/pages/Screener.tsx
index 2970546..3db438b 100644
--- a/frontend/src/pages/Screener.tsx
+++ b/frontend/src/pages/Screener.tsx
@@ -3,6 +3,7 @@ import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
 import { motion } from 'framer-motion'
 import { ScanSearch, Clock, TrendingUp, Star, Filter, Layers, Network, Sparkles, RefreshCw, Settings2, Store } from 'lucide-react'
 import { api, genRuleId, type ScreenerStrategy, type ScreenerResult } from '@/lib/api'
+import { toast } from '@/components/Toast'
 import { useDataStatus, usePreferences } from '@/lib/useSharedQueries'
 import { useWatchlistBatchAdd } from '@/lib/useSharedMutations'
 import { QK } from '@/lib/queryKeys'
@@ -146,11 +147,23 @@ export function Screener() {
 
   // 策略列表加载后,自动清除池中失效的自定义策略(如本地开发残留的、
   // 当前后端已不存在的策略 ID),避免"策略池"对话框持续显示失效项。
-  // availableStrategyIds 初始为空集合时跳过,防止首次渲染误清整个池。
+  // 关键: 仅当本次拉取成功且返回非空列表时才 prune。
+  // 拉取中/失败/返回空(如引擎 reload 瞬时把某策略跳过)时一律不碰池,
+  // 否则会把用户池里仍有效的 ID 永久清空并写入 localStorage,导致卡片全没。
   useEffect(() => {
-    if (availableStrategyIds.size === 0) return
+    if (strategies.isError) return        // 拉取失败: 不 prune
+    if (!strategies.isSuccess) return     // 加载中: 不 prune
+    if (availableStrategyIds.size === 0) return  // 空列表: 不 prune
     prune(availableStrategyIds)
-  }, [availableStrategyIds, prune])
+  }, [availableStrategyIds, prune, strategies.isError, strategies.isSuccess])
+
+  // 策略文件加载失败时提示用户(避免"策略静默消失"被误判为正常)
+  const loadErrors = strategies.data?.load_errors ?? []
+  useEffect(() => {
+    for (const e of loadErrors) {
+      toast(`策略「${e.file}」加载失败：${e.error}`, 'error')
+    }
+  }, [loadErrors])
 
   // 进入页面自动跑策略池中的策略，获取命中数
   const runAll = useMutation({