diff --git a/.agents/skills/unidesk-webdev/SKILL.md b/.agents/skills/unidesk-webdev/SKILL.md
index 368ec98f..23023319 100644
--- a/.agents/skills/unidesk-webdev/SKILL.md
+++ b/.agents/skills/unidesk-webdev/SKILL.md
@@ -47,7 +47,7 @@ web-probe 入口分三类：
 
 - `run`：repo-owned 标准 DOM probe，适合固定 P4 验收和已有脚本。
 - `script`：受控 Playwright 托管脚本，适合一轮 55 秒内完成的 DOM/API 断言、截图、route/intercept 和边界采样。
-- `observe`：纯客户端长程观测，适合同一 Workbench session 多轮任务、realtime/projection 问题、长时间 trace/DOM/network 采样和无副作用报告生成。长程 Workbench 观测默认同时打开两个浏览器页面：control 页面只执行显式 `observe command` 用户动作，observer 页面只打开同一个 session 做被动观察，用来抓多用户/多页面下同一 session 的投影差异、历史 trace 丢失、耗时跳变和 loading 差异。
+- `observe`：纯客户端长程观测，适合同一 Workbench session 多轮任务、realtime/projection 问题、长时间 trace/DOM/network 采样和无副作用报告生成。长程 Workbench 观测默认同时打开两个浏览器页面：control 页面只执行显式 `observe command` 用户动作，observer 页面只打开同一个 session 做被动观察，并默认每 3 分钟整页刷新一次同一 session，模拟用户离开后返回，用来抓多用户/多页面下同一 session 的投影差异、历史 trace 丢失、耗时跳变和 loading 差异。
 
 需要 Playwright route/intercept、延迟 API、读取 in-flight DOM 或截图时仍使用受控 `web-probe script`，不要裸写 Playwright：
 
@@ -94,7 +94,7 @@ bun scripts/cli.ts hwlab nodes web-probe observe analyze webobs-xxxx
 约束：
 
 - `web-probe script` 不运行默认探针，必须通过 stdin heredoc 或 `--script-file <path>` 提供脚本；只需要 repo-owned 标准 DOM probe 时使用 `web-probe run`。
-- `web-probe observe start` 默认是被动观测：记录 DOM 摘要、自然页面 request/response/requestfailed、截图和 performance 样本，不主动 fetch Workbench API、不 reload、不切换 session、不拦截路由、不调用 repair helper。长程 Workbench 观测必须保留 control/observer 双页面模型：control 页面执行显式 command，observer 页面只同步到同一 session URL 后被动采样；两页的 `pageRole`、`pageId`、`sampleGroupSeq` 必须进入样本和 analyzer 报表。任何 `newSession`、`selectProvider`、`sendPrompt`、`goto`、`screenshot`、`mark`、`stop` 都必须通过 `observe command` 显式下发，并进入 `control.jsonl`。
+- `web-probe observe start` 默认是被动观测：记录 DOM 摘要、自然页面 request/response/requestfailed、截图和 performance 样本，不主动 fetch Workbench API、不切换 control session、不拦截路由、不调用 repair helper。长程 Workbench 观测必须保留 control/observer 双页面模型：control 页面执行显式 command，observer 页面只同步到同一 session URL 后被动采样，并按默认 180000ms 周期整页刷新同一 session 来模拟用户往返；周期刷新只作用于 observer，不得改变 control active session 或作为通过条件。两页的 `pageRole`、`pageId`、`sampleGroupSeq` 必须进入样本和 analyzer 报表。任何 `newSession`、`selectProvider`、`sendPrompt`、`goto`、`screenshot`、`mark`、`stop` 都必须通过 `observe command` 显式下发，并进入 `control.jsonl`。
 - `web-probe observe` 的 issue evidence 优先记录 observer id、stateDir、report JSON/Markdown SHA、samples/control/network/artifact 计数、routeSessionId、activeSessionId、prompt hash/textBytes、traceId、AgentRun runId/commandId、最终 status 和必要摘要；不要把 prompt 原文、assistant 大段正文、完整 stdout/stderr 或 provider payload 粘贴到 issue。
 - 多轮 Workbench 采样必须证明同一个 `sessionId` 连续承载所有轮次；每轮至少记录 prompt hash、traceId、终态、最终回答摘要和性能/产物表。若 Web UI 投影卡住但 Code Agent/AgentRun result 已 terminal，应同时登记“执行终态”和“Workbench 投影未收敛”，不得用 `goto`、reload、切 session 或 result polling 把 UI 失败伪装成通过。
 - `observe analyze` 是离线分析，只读取 artifact JSONL 并写 `analysis/report.md` 与 `analysis/report.json`，不访问 Workbench API、不驱动浏览器。报告必须输出采样点 vs 每个 turn 的总耗时/最近更新时间表、可见“加载中”的数量/归属/并发 owner/连续出现区间、DOM diagnostic/HTTP/console/requestfailed/runtime execution error 分组、page asset provenance segment、同源 API Resource Timing 分位表和超过 5s 的慢路径 finding；页面/API 加载超过 5s 视为不可用级性能红线，可见“加载中”持续超过 5s 也必须作为真实慢加载证据登记到上游问题。修复必须降低真实请求、投影、渲染或后端路径耗时，禁止为了减少“加载中”出现时间而提前展示未加载完的内容，也不能靠下游 retry/reload/fallback 掩盖。报告里的 `final-response-flicker`、`uncommanded-visible-state-change`、session changed、network 503 等 finding 是排障线索；用于 closeout 时必须结合原始 session/trace/DOM 证据解释，避免把采样噪声直接当作业务结论。
diff --git a/scripts/src/hwlab-node-web-observe-runner-source.ts b/scripts/src/hwlab-node-web-observe-runner-source.ts
index eb2aa9ff..6318841b 100644
--- a/scripts/src/hwlab-node-web-observe-runner-source.ts
+++ b/scripts/src/hwlab-node-web-observe-runner-source.ts
@@ -20,6 +20,7 @@ const targetPath = process.env.UNIDESK_WEB_OBSERVE_TARGET_PATH || "/workbench";
 const sampleIntervalMs = positiveInteger(process.env.UNIDESK_WEB_OBSERVE_SAMPLE_INTERVAL_MS, 5000);
 const screenshotIntervalMs = positiveInteger(process.env.UNIDESK_WEB_OBSERVE_SCREENSHOT_INTERVAL_MS, 300000);
 const maxSamples = positiveInteger(process.env.UNIDESK_WEB_OBSERVE_MAX_SAMPLES, 0);
+const observerRefreshIntervalMs = positiveInteger(process.env.UNIDESK_WEB_OBSERVE_OBSERVER_REFRESH_INTERVAL_MS, 180000);
 const viewport = parseViewport(process.env.UNIDESK_WEB_OBSERVE_VIEWPORT || "1440x900");
 const playwrightProxy = proxyConfigFromEnv(baseUrl);
 const chromiumLaunchOptions = chromiumLaunchOptionsForProxy(playwrightProxy);
@@ -48,6 +49,7 @@ let browser;
 let context;
 let page;
 let observerPage;
+let lastObserverRefreshAtMs = Date.now();
 let sampleSeq = 0;
 let commandSeq = 0;
 let artifactSeq = 0;
@@ -119,7 +121,7 @@ async function writeManifest(extra = {}) {
     network: publicNetwork(playwrightProxy),
     pageAuthority: { browser: "chromium", context: "shared-auth", pageMode: "dual-control-observer", controlPageId: pageId, observerPageId, continuityBreaksRecorded: true },
     pageProvenance: compactPageProvenance(currentPageProvenance),
-    sampling: { mode: "passive", sampleIntervalMs, screenshotIntervalMs, maxSamples, observerInitiatedDefault: false, responseBodyReadDefault: false },
+    sampling: { mode: "passive", sampleIntervalMs, screenshotIntervalMs, maxSamples, observerRefreshIntervalMs, observerInitiatedDefault: false, responseBodyReadDefault: false },
     commandDirs: dirs,
     artifacts: files,
     safety: { pureClient: true, inboundApi: false, database: false, queueConsumer: false, k8sWorkload: false, valuesRedacted: true, secretValuesPrinted: false },
@@ -141,6 +143,8 @@ async function writeHeartbeat(extra = {}) {
     baseUrl,
     currentUrl: currentPageUrl(),
     observerUrl: pageUrl(observerPage),
+    observerRefreshIntervalMs,
+    lastObserverRefreshAt: Number.isFinite(lastObserverRefreshAtMs) ? new Date(lastObserverRefreshAtMs).toISOString() : null,
     pageProvenance: compactPageProvenance(currentPageProvenance),
     sampleSeq,
     commandSeq,
@@ -259,14 +263,15 @@ async function withObserverSync(result, reason) {
   return { ...result, observer: await syncObserverPageToControlSession(reason, result?.sessionId ?? null) };
 }
 
-async function syncObserverPageToControlSession(reason, explicitSessionId = null) {
+async function syncObserverPageToControlSession(reason, explicitSessionId = null, options = {}) {
   if (!observerPage || observerPage.isClosed()) return { ok: false, reason, pageRole: "observer", pageId: observerPageId, failureKind: "observer-page-unavailable" };
+  const forceRefresh = options?.forceRefresh === true;
   const snapshot = await workbenchSessionSnapshot();
   const sessionId = explicitSessionId || snapshot?.activeSessionId || snapshot?.routeSessionId || routeSessionIdFromUrl(currentPageUrl());
   const target = sessionId ? "/workbench/sessions/" + encodeURIComponent(sessionId) : targetPath;
   const beforeUrl = pageUrl(observerPage);
   const beforeSessionId = routeSessionIdFromUrl(beforeUrl);
-  if (sessionId && beforeSessionId === sessionId) return { ok: true, reason, changed: false, sessionId, beforeUrl, afterUrl: beforeUrl, pageRole: "observer", pageId: observerPageId };
+  if (sessionId && beforeSessionId === sessionId && !forceRefresh) return { ok: true, reason, changed: false, observerRoundTrip: false, sessionId, beforeUrl, afterUrl: beforeUrl, pageRole: "observer", pageId: observerPageId };
   let status = null;
   let statusText = null;
   const response = await observerPage.goto(new URL(target, baseUrl).toString(), { waitUntil: "domcontentloaded", timeout: 45000 }).catch((error) => ({ observerGotoError: errorSummary(error) }));
@@ -274,7 +279,24 @@ async function syncObserverPageToControlSession(reason, explicitSessionId = null
   status = typeof response?.status === "function" ? response.status() : null;
   statusText = typeof response?.statusText === "function" ? response.statusText() : null;
   await observerPage.waitForTimeout(1000);
-  return { ok: true, reason, changed: true, sessionId: sessionId ?? null, targetPath: target, beforeUrl, afterUrl: pageUrl(observerPage), pageRole: "observer", pageId: observerPageId, httpStatus: status, statusText, valuesRedacted: true };
+  lastObserverRefreshAtMs = Date.now();
+  return { ok: true, reason, changed: true, observerRoundTrip: forceRefresh, sessionId: sessionId ?? null, targetPath: target, beforeUrl, afterUrl: pageUrl(observerPage), pageRole: "observer", pageId: observerPageId, httpStatus: status, statusText, valuesRedacted: true };
+}
+
+async function maybeRefreshObserverPage(reason) {
+  if (!observerPage || observerPage.isClosed()) return null;
+  if (!observerRefreshIntervalMs || observerRefreshIntervalMs <= 0) return null;
+  if (Date.now() - lastObserverRefreshAtMs < observerRefreshIntervalMs) return null;
+  const result = await syncObserverPageToControlSession("observer-periodic-refresh", null, { forceRefresh: true });
+  await appendJsonl(files.control, eventRecord("observer-periodic-refresh", {
+    pageRole: "observer",
+    pageId: observerPageId,
+    reason,
+    intervalMs: observerRefreshIntervalMs,
+    result,
+    valuesRedacted: true
+  }));
+  return result;
 }
 
 async function runControlCommand(command, fn) {
@@ -918,6 +940,7 @@ async function preflightSummary() {
 }
 
 async function samplePage(reason) {
+  await maybeRefreshObserverPage(reason);
   const groupSeq = sampleSeq + 1;
   if (page && !page.isClosed()) await sampleOnePage(page, { reason, groupSeq, pageRole: "control", targetPageId: pageId });
   if (observerPage && !observerPage.isClosed()) {
@@ -3825,7 +3848,7 @@ function compactManifest(value) {
 
 function compactHeartbeat(value) {
   if (!value) return null;
-  return { jobId: value.jobId, pid: value.pid, status: value.status, sampleSeq: value.sampleSeq, commandSeq: value.commandSeq, pageId: value.pageId ?? null, observerPageId: value.observerPageId ?? null, currentUrl: value.currentUrl, observerUrl: value.observerUrl ?? null, pageProvenance: value.pageProvenance ?? null, updatedAt: value.updatedAt, uptimeMs: value.uptimeMs };
+  return { jobId: value.jobId, pid: value.pid, status: value.status, sampleSeq: value.sampleSeq, commandSeq: value.commandSeq, pageId: value.pageId ?? null, observerPageId: value.observerPageId ?? null, currentUrl: value.currentUrl, observerUrl: value.observerUrl ?? null, observerRefreshIntervalMs: value.observerRefreshIntervalMs ?? null, lastObserverRefreshAt: value.lastObserverRefreshAt ?? null, pageProvenance: value.pageProvenance ?? null, updatedAt: value.updatedAt, uptimeMs: value.uptimeMs };
 }
 
 function renderTurnTimingTable(sampleMetrics) {