diff --git a/scripts/src/dev-cloud-workbench-smoke-lib.mjs b/scripts/src/dev-cloud-workbench-smoke-lib.mjs
index 4dba9618..cff7ae0e 100644
--- a/scripts/src/dev-cloud-workbench-smoke-lib.mjs
+++ b/scripts/src/dev-cloud-workbench-smoke-lib.mjs
@@ -293,6 +293,11 @@ function runStaticSmoke() {
     evidence: ["/health/live", "/v1", "/v1/agent/chat", "/json-rpc", ...readOnlyRpcMethods]
   });
 
+  addCheck(checks, blockers, "api-degraded-default-status", hasApiDegradedDefaultStatus(files), "Default workbench status distinguishes reachable degraded API from fully OK without exposing backend blocker details.", {
+    blocker: "observability_blocker",
+    evidence: ["healthLive.data.status === degraded", "API 降级 / 只读模式", "no Gate/diagnostics/blocker copy in default status classifier"]
+  });
+
   addCheck(checks, blockers, "code-agent-chat-primary-flow", hasCodeAgentChatContract(files), "Center Agent conversation sends to the controlled Code Agent chat endpoint and no longer uses 添加草稿 as the primary flow.", {
     blocker: "runtime_blocker",
     evidence: ["command-send", "agent-chat-status", "/v1/agent/chat", "conversationId/messageId/status/timestamps/error.message"]
@@ -1067,6 +1072,18 @@ function hasSameOriginReadOnlyBoundary(app) {
   );
 }
 
+function hasApiDegradedDefaultStatus({ app }) {
+  const statusBody = functionBody(app, "workbenchApiSurfaceStatus");
+  return (
+    /function\s+workbenchApiSurfaceStatus\s*\(/u.test(app) &&
+    /live\.healthLive\?\.data\?\.status/u.test(statusBody) &&
+    /healthLiveStatus === "degraded"/u.test(statusBody) &&
+    /API 降级 \/ 只读模式/u.test(statusBody) &&
+    /同源 API 可响应但处于降级状态；当前保持只读查看和本地任务整理。/u.test(statusBody) &&
+    !/blocker|DB live readiness|Gate|诊断|验收|M0-M5|执行轨迹/u.test(statusBody)
+  );
+}
+
 function hasCodeAgentChatContract({ html, app }) {
   return (
     /id=["']agent-chat-status["']/u.test(html) &&
@@ -1666,6 +1683,27 @@ async function inspectJourneyUi(page) {
   }));
 }
 
+async function inspectDefaultApiStatus(page) {
+  return page.evaluate(() => {
+    const liveStatus = document.querySelector("#live-status")?.textContent?.trim() ?? "";
+    const liveDetail = document.querySelector("#live-detail")?.textContent?.trim() ?? "";
+    const methodText = [...document.querySelectorAll("#method-list .badge")].map((element) => element.textContent?.trim() ?? "");
+    const firstScreenText = document.querySelector(".topbar")?.textContent?.replace(/\s+/gu, " ").trim() ?? "";
+    const forbidden = /Gate|诊断|验收|BLOCKED|M0-M5|执行轨迹|runtime_durable_adapter_query_blocked|DB live readiness/u;
+    return {
+      liveStatus,
+      liveDetail,
+      methodText,
+      firstScreenText,
+      degradedStatusVisible:
+        liveStatus === "API 降级 / 只读模式" &&
+        liveDetail === "同源 API 可响应但处于降级状态；当前保持只读查看和本地任务整理。" &&
+        methodText.includes("system.health"),
+      defaultCopyIsWorkbenchSafe: !forbidden.test(`${liveStatus} ${liveDetail} ${firstScreenText}`)
+    };
+  });
+}
+
 function sanitizeAgentChatBody(body) {
   if (!body || typeof body !== "object") return null;
   return {
@@ -1728,7 +1766,13 @@ export async function runDevCloudWorkbenchLocalAgentFixtureSmoke() {
 
     await page.goto(server.url, { waitUntil: "networkidle", timeout: 15000 });
     await page.locator("#command-input").waitFor({ state: "visible", timeout: 12000 });
+    await page.waitForFunction(
+      () => document.querySelector("#live-status")?.textContent?.trim() === "API 降级 / 只读模式",
+      null,
+      { timeout: 8000 }
+    );
     const controls = await inspectJourneyControls(page);
+    const apiStatus = await inspectDefaultApiStatus(page);
     await page.locator("#command-input").fill("请用一句话说明当前 HWLAB 工作台可以做什么。");
     const responsePromise = page.waitForResponse(
       (response) => response.url().includes("/v1/agent/chat") && response.request().method() === "POST",
@@ -1761,6 +1805,12 @@ export async function runDevCloudWorkbenchLocalAgentFixtureSmoke() {
         summary: "Local SOURCE fixture browser smoke can locate the Code Agent input, send button, thread, and right-side evidence panels.",
         observations: controls
       },
+      {
+        id: "local-api-degraded-default-status",
+        status: apiStatus.degradedStatusVisible && apiStatus.defaultCopyIsWorkbenchSafe ? "pass" : "blocked",
+        summary: "Default workbench status renders reachable degraded /health/live as API degraded read-only without first-screen backend blocker details.",
+        observations: apiStatus
+      },
       {
         id: "local-agent-fixture-replied-state",
         status: pass ? "pass" : "blocked",
diff --git a/web/hwlab-cloud-web/app.mjs b/web/hwlab-cloud-web/app.mjs
index b864b962..e736ca2d 100644
--- a/web/hwlab-cloud-web/app.mjs
+++ b/web/hwlab-cloud-web/app.mjs
@@ -508,27 +508,54 @@ function nextProtocolId(prefix) {
 function renderLiveSurface(live) {
   state.liveSurface = live;
   const coreProbes = [live.healthLive, live.restIndex, live.health, live.adapter];
-  const reachable = coreProbes.some((probe) => probe.ok);
+  const surfaceStatus = workbenchApiSurfaceStatus(live, coreProbes);
   const runtimeSummary = runtimeSummaryFrom(live);
   const methods = methodsFrom(live);
 
-  el.liveStatus.textContent = reachable ? "只读连接可用" : "离线查看";
-  el.liveStatus.className = `tone-${toneClass(reachable ? "dev-live" : "source")}`;
+  el.liveStatus.textContent = surfaceStatus.label;
+  el.liveStatus.className = `tone-${toneClass(surfaceStatus.tone)}`;
   state.codeAgentAvailability = codeAgentAvailabilityFrom(live);
-  el.liveDetail.textContent = reachable
-    ? codeAgentAvailabilitySummary()
-    : "同源 API 暂不可用，当前仍可使用本地草稿和已加载资源。";
+  el.liveDetail.textContent = surfaceStatus.detail ?? codeAgentAvailabilitySummary();
 
   renderAgentChatStatus(deriveAgentChatStatus());
   renderHardwareStatus(runtimeSummary);
   renderWiringList(runtimeSummary);
   renderRecords(live);
   renderDiagnostics(live);
-  renderMethodList(methods.length > 0 ? methods.filter((method) => rpcReadMethods.includes(method)) : rpcReadMethods, reachable ? "live" : "degraded");
+  renderMethodList(methods.length > 0 ? methods.filter((method) => rpcReadMethods.includes(method)) : rpcReadMethods, surfaceStatus.methodTone);
   renderConversation();
   renderDrafts();
 }
 
+function workbenchApiSurfaceStatus(live, coreProbes = [live.healthLive, live.restIndex, live.health, live.adapter]) {
+  const reachable = coreProbes.some((probe) => probe.ok);
+  if (!reachable) {
+    return {
+      label: "离线查看",
+      tone: "source",
+      methodTone: "degraded",
+      detail: "同源 API 暂不可用，当前仍可使用本地草稿和已加载资源。"
+    };
+  }
+
+  const healthLiveStatus = String(live.healthLive?.data?.status ?? "").trim().toLowerCase();
+  if (live.healthLive?.ok && healthLiveStatus === "degraded") {
+    return {
+      label: "API 降级 / 只读模式",
+      tone: "degraded",
+      methodTone: "degraded",
+      detail: "同源 API 可响应但处于降级状态；当前保持只读查看和本地任务整理。"
+    };
+  }
+
+  return {
+    label: "只读连接可用",
+    tone: "dev-live",
+    methodTone: "live",
+    detail: null
+  };
+}
+
 function renderResourceTree() {
   const items = [
     {
diff --git a/web/hwlab-cloud-web/scripts/check.mjs b/web/hwlab-cloud-web/scripts/check.mjs
index 6d3191c8..d321f629 100644
--- a/web/hwlab-cloud-web/scripts/check.mjs
+++ b/web/hwlab-cloud-web/scripts/check.mjs
@@ -280,6 +280,12 @@ assert.match(distContractScript, /diagnostics\/gate\/index\.html/);
 assert.match(markedLicense, /MarkedJS/);
 assert.match(markedLicense, /Permission is hereby granted, free of charge/);
 assert.match(html, /live-status/);
+assert.match(app, /function workbenchApiSurfaceStatus/);
+assert.match(functionBody(app, "workbenchApiSurfaceStatus"), /live\.healthLive\?\.data\?\.status/);
+assert.match(functionBody(app, "workbenchApiSurfaceStatus"), /healthLiveStatus === "degraded"/);
+assert.match(app, /API 降级 \/ 只读模式/);
+assert.match(app, /同源 API 可响应但处于降级状态；当前保持只读查看和本地任务整理。/);
+assert.doesNotMatch(functionBody(app, "workbenchApiSurfaceStatus"), /blocker|DB live readiness|Gate|诊断|验收|M0-M5|执行轨迹/u);
 assert.match(html, /method-list/);
 assert.match(html, /quick-actions/);
 assert.match(html, /编写任务/);