diff --git a/frontend-web/src/components/workspace/artifacts/artifact-file-detail.tsx b/frontend-web/src/components/workspace/artifacts/artifact-file-detail.tsx
index bed8565b..a938bb46 100644
--- a/frontend-web/src/components/workspace/artifacts/artifact-file-detail.tsx
+++ b/frontend-web/src/components/workspace/artifacts/artifact-file-detail.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import {
+import {
   ArrowDownIcon,
   Code2Icon,
   CopyIcon,
@@ -14,24 +14,24 @@ import {
   SparklesIcon,
   UploadCloudIcon,
   XIcon,
-} from "lucide-react";
-import { useQueryClient } from "@tanstack/react-query";
-import { useParams } from "next/navigation";
+} from "lucide-react";
+import { useQueryClient } from "@tanstack/react-query";
+import { useParams } from "next/navigation";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import type { AnchorHTMLAttributes, HTMLAttributes, ReactNode } from "react";
-import { toast } from "sonner";
-import { defaultUrlTransform } from "react-markdown";
-import { Streamdown } from "streamdown";
+import { toast } from "sonner";
+import { defaultUrlTransform } from "react-markdown";
+import { Streamdown } from "streamdown";
 
-import {
-  Artifact,
+import {
+  Artifact,
   ArtifactAction,
   ArtifactActions,
   ArtifactContent,
   ArtifactHeader,
   ArtifactTitle,
-} from "@/components/ai-elements/artifact";
-import { DocumentRewriteDialog } from "@/components/workspace/artifacts/document-rewrite-dialog";
+} from "@/components/ai-elements/artifact";
+import { DocumentRewriteDialog } from "@/components/workspace/artifacts/document-rewrite-dialog";
 import { Select, SelectItem } from "@/components/ui/select";
 import {
   SelectContent,
@@ -41,23 +41,23 @@ import {
 } from "@/components/ui/select";
 import { ToggleGroup, ToggleGroupItem } from "@/components/ui/toggle-group";
 import { CodeEditor } from "@/components/workspace/code-editor";
-import { MarkdownAiEditor } from "@/open-canvas/components/artifact/MarkdownAiEditor";
-import { useDocumentRewrite } from "@/open-canvas/hooks/useDocumentRewrite";
-import { useCapabilities as useResearchCapabilities } from "@/strategy-components/api/deep-research";
-import {
-  listDurableDocumentRewrites,
-  streamDurableDocumentRewriteJob,
-  type DocumentRewriteSummary,
-  type DocumentRewriteStreamEvent,
-} from "@/open-canvas/api/rewrite";
+import { MarkdownAiEditor } from "@/open-canvas/components/artifact/MarkdownAiEditor";
+import { useDocumentRewrite } from "@/open-canvas/hooks/useDocumentRewrite";
+import { useCapabilities as useResearchCapabilities } from "@/strategy-components/api/deep-research";
+import {
+  listDurableDocumentRewrites,
+  streamDurableDocumentRewriteJob,
+  type DocumentRewriteSummary,
+  type DocumentRewriteStreamEvent,
+} from "@/open-canvas/api/rewrite";
 import { publishArtifactToKnowledge } from "@/core/agents/api";
-import { useAgent } from "@/core/agents/hooks";
-import { apiFetch } from "@/core/api";
-import { copyTextToClipboard } from "@/core/clipboard";
-import {
-  DOCUMENT_REWRITE_UNDONE_EVENT,
-  useDocumentRewritePresentation,
-} from "@/core/document-rewrite/context";
+import { useAgent } from "@/core/agents/hooks";
+import { apiFetch } from "@/core/api";
+import { copyTextToClipboard } from "@/core/clipboard";
+import {
+  DOCUMENT_REWRITE_UNDONE_EVENT,
+  useDocumentRewritePresentation,
+} from "@/core/document-rewrite/context";
 import {
   downloadArtifactFile,
 } from "@/core/artifacts/download";
@@ -66,6 +66,7 @@ import {
   useUpdateArtifactContent,
 } from "@/core/artifacts/hooks";
 import { resolveArtifactURL, urlOfArtifact } from "@/core/artifacts/utils";
+import { isArtifactApiPath } from "@/core/artifacts/streaming-write-preview";
 import { useI18n } from "@/core/i18n/hooks";
 import { downloadMarkdownAsDocx } from "@/core/scheduled-tasks/markdown-docx";
 import { streamdownPlugins } from "@/core/streamdown";
@@ -99,16 +100,16 @@ import { useArtifacts } from "./context";
 import { SpreadsheetPreview } from "./spreadsheet-preview";
 import { SkillInstallDialog } from "./skill-install-dialog";
 
-const SANDBOX_RESUME_EVENT = "workspace:sandbox-resume-autoscroll";
-
-async function sha256Content(content: string): Promise<string | undefined> {
-  if (!globalThis.crypto?.subtle) return undefined;
-  const digest = await globalThis.crypto.subtle.digest(
-    "SHA-256",
-    new TextEncoder().encode(content),
-  );
-  return Array.from(new Uint8Array(digest), (byte) => byte.toString(16).padStart(2, "0")).join("");
-}
+const SANDBOX_RESUME_EVENT = "workspace:sandbox-resume-autoscroll";
+
+async function sha256Content(content: string): Promise<string | undefined> {
+  if (!globalThis.crypto?.subtle) return undefined;
+  const digest = await globalThis.crypto.subtle.digest(
+    "SHA-256",
+    new TextEncoder().encode(content),
+  );
+  return Array.from(new Uint8Array(digest), (byte) => byte.toString(16).padStart(2, "0")).join("");
+}
 
 function extractTextFromChildren(children: ReactNode): string {
   if (typeof children === "string" || typeof children === "number") return String(children);
@@ -151,13 +152,13 @@ export function ArtifactFileDetail({
   onClose,
   allowVirtualMarkdownEdit = false,
   disableDesensitize = false,
-  hideFileName = false,
-  onDownloadClick,
-  toolbarActions,
-  headerLeadingAction,
-  headerLeadingActionBare = false,
-  researchSessionId,
-}: {
+  hideFileName = false,
+  onDownloadClick,
+  toolbarActions,
+  headerLeadingAction,
+  headerLeadingActionBare = false,
+  researchSessionId,
+}: {
   className?: string;
   filepath: string;
   threadId: string;
@@ -183,22 +184,22 @@ export function ArtifactFileDetail({
    * （深度研究沙箱用它弹「Markdown / Word」格式选择弹窗），并隐藏工具栏中重复的
    * 「另存为 Word」。默认不传 —— 其它调用方行为不变。
    */
-  onDownloadClick?: () => void;
-  /** Deep-research reports use protected `deep-research://` image references. */
-  researchSessionId?: string;
-  /**
-   * 由宿主注入到右上角 ArtifactActions 图标组的动作。深度研究报告使用它
-   * 放置全文改写入口，避免再在沙箱内容区叠一个文字按钮。
-   */
-  toolbarActions?: ReactNode;
-  /** Replaces the left file-type badge for an embedded workspace action. */
-  headerLeadingAction?: ReactNode;
-  /**
-   * 嵌入式工作区的标题动作可直接放在标题栏中，避免再被文件类型徽标的胶囊容器包一层。
-   * 默认保留原有徽标容器，避免影响普通聊天和产物预览。
-   */
-  headerLeadingActionBare?: boolean;
-}) {
+  onDownloadClick?: () => void;
+  /** Deep-research reports use protected `deep-research://` image references. */
+  researchSessionId?: string;
+  /**
+   * 由宿主注入到右上角 ArtifactActions 图标组的动作。深度研究报告使用它
+   * 放置全文改写入口，避免再在沙箱内容区叠一个文字按钮。
+   */
+  toolbarActions?: ReactNode;
+  /** Replaces the left file-type badge for an embedded workspace action. */
+  headerLeadingAction?: ReactNode;
+  /**
+   * 嵌入式工作区的标题动作可直接放在标题栏中，避免再被文件类型徽标的胶囊容器包一层。
+   * 默认保留原有徽标容器，避免影响普通聊天和产物预览。
+   */
+  headerLeadingActionBare?: boolean;
+}) {
   const { t } = useI18n();
   const { artifacts, setOpen, select } = useArtifacts();
   const { isMock, thread, publicShareCode } = useThread();
@@ -295,7 +296,7 @@ export function ArtifactFileDetail({
     enabled: isCodeFile && !useWriteFileStreaming,
   });
 
-  const canEditArtifact =
+  const canEditArtifact =
     language === "markdown" &&
     !useWriteFileStreaming &&
     !isSkillFile &&
@@ -303,36 +304,36 @@ export function ArtifactFileDetail({
   // 「AI 写作」md 展示开关：只要是可编辑的 markdown 就提供「AI 写作」视图（在 源码/预览 旁多一个
   // 切换项），用户可随时切过去体验划词「AI 改写」。默认仍是「预览」，避免编辑器在内容加载期间
   // 挂载导致白屏 + 避免复杂 md(表格/公式/HTML)误入有损编辑。
-  const canUseAiEditor = canEditArtifact;
-  const [draftContent, setDraftContent] = useState("");
-  const [hasLocalEdits, setHasLocalEdits] = useState(false);
-  const [documentRewriteDialogOpen, setDocumentRewriteDialogOpen] = useState(false);
-  const [documentRewritePresentationId, setDocumentRewritePresentationId] = useState<string | null>(null);
-  const updateArtifact = useUpdateArtifactContent();
-  const queryClient = useQueryClient();
-  const documentRewrite = useDocumentRewrite();
-  const imageCapabilities = useResearchCapabilities();
-  const rewritePresentation = useDocumentRewritePresentation();
-  const hydratedRewriteScopeRef = useRef<string | null>(null);
-  const mirroredRequirementsPlanRef = useRef<{ presentationId: string | null; plan: string }>({
-    presentationId: null,
-    plan: "",
-  });
-  const mirroredThinkingTextRef = useRef<{ presentationId: string | null; thinking: string }>({
-    presentationId: null,
-    thinking: "",
-  });
-  const documentRewriteActive = documentRewrite.isActive;
-  const imageGenerationAvailable = imageCapabilities.data?.imageGeneration?.available === true;
-  const maxGeneratedImages = imageCapabilities.data?.imageGeneration?.maxImages ?? 4;
-  const canUseFullDocumentRewrite = canEditArtifact && !hasLocalEdits;
-  const displayContent = documentRewriteActive
-    ? documentRewrite.run.draft
-    : (canEditArtifact ? draftContent : (content ?? ""));
+  const canUseAiEditor = canEditArtifact;
+  const [draftContent, setDraftContent] = useState("");
+  const [hasLocalEdits, setHasLocalEdits] = useState(false);
+  const [documentRewriteDialogOpen, setDocumentRewriteDialogOpen] = useState(false);
+  const [documentRewritePresentationId, setDocumentRewritePresentationId] = useState<string | null>(null);
+  const updateArtifact = useUpdateArtifactContent();
+  const queryClient = useQueryClient();
+  const documentRewrite = useDocumentRewrite();
+  const imageCapabilities = useResearchCapabilities();
+  const rewritePresentation = useDocumentRewritePresentation();
+  const hydratedRewriteScopeRef = useRef<string | null>(null);
+  const mirroredRequirementsPlanRef = useRef<{ presentationId: string | null; plan: string }>({
+    presentationId: null,
+    plan: "",
+  });
+  const mirroredThinkingTextRef = useRef<{ presentationId: string | null; thinking: string }>({
+    presentationId: null,
+    thinking: "",
+  });
+  const documentRewriteActive = documentRewrite.isActive;
+  const imageGenerationAvailable = imageCapabilities.data?.imageGeneration?.available === true;
+  const maxGeneratedImages = imageCapabilities.data?.imageGeneration?.maxImages ?? 4;
+  const canUseFullDocumentRewrite = canEditArtifact && !hasLocalEdits;
+  const displayContent = documentRewriteActive
+    ? documentRewrite.run.draft
+    : (canEditArtifact ? draftContent : (content ?? ""));
   const isAutoPreviewLanguage =
     language === "html" || language === "markdown" || language === "mermaid";
-  const isPreviewStreaming =
-    isAutoPreviewLanguage && (thread.isLoading || documentRewriteActive);
+  const isPreviewStreaming =
+    isAutoPreviewLanguage && (thread.isLoading || documentRewriteActive);
   const hasMultipleArtifacts = (artifacts?.length ?? 0) > 1;
   const fileTypeLabel = useMemo(() => {
     if (isImageFile(filepath)) return "IMG";
@@ -345,7 +346,7 @@ export function ArtifactFileDetail({
     return "FILE";
   }, [filepath, isSkillFile, isSpreadsheetFile, language]);
 
-  const [viewMode, setViewMode] = useState<"code" | "preview" | "edit">("code");
+  const [viewMode, setViewMode] = useState<"code" | "preview" | "edit">("code");
   const [allowAutoViewSwitch, setAllowAutoViewSwitch] = useState(true);
   const [installDialogOpen, setInstallDialogOpen] = useState(false);
   const [showPreviewSwitchPulse, setShowPreviewSwitchPulse] = useState(false);
@@ -358,346 +359,346 @@ export function ArtifactFileDetail({
     null,
   );
   const artifactContentRef = useRef<HTMLDivElement | null>(null);
-  const resumeButtonTimeoutRef = useRef<number | null>(null);
-
-  useEffect(() => {
-    if (!documentRewriteActive) return;
-    setAllowAutoViewSwitch(false);
-    setAutoScrollEnabled(true);
-    setShowResumeAutoScroll(false);
-    setViewMode("code");
-  }, [documentRewriteActive]);
+  const resumeButtonTimeoutRef = useRef<number | null>(null);
+
+  useEffect(() => {
+    if (!documentRewriteActive) return;
+    setAllowAutoViewSwitch(false);
+    setAutoScrollEnabled(true);
+    setShowResumeAutoScroll(false);
+    setViewMode("code");
+  }, [documentRewriteActive]);
 
   useEffect(() => {
     setDraftContent(content ?? "");
     setHasLocalEdits(false);
   }, [filepathFromProps]);
 
-  useEffect(() => {
-    if (!canEditArtifact || hasLocalEdits || documentRewriteActive) {
-      return;
-    }
-    setDraftContent(content ?? "");
-  }, [canEditArtifact, content, documentRewriteActive, hasLocalEdits]);
-
-  useEffect(() => {
-    if (
-      !canEditArtifact ||
-      !threadId ||
-      !filepath ||
-      isMock ||
-      useWriteFileStreaming ||
-      documentRewriteActive
-    ) {
-      return;
-    }
-    const scope = `${threadId}:${filepath}`;
-    if (hydratedRewriteScopeRef.current === scope) return;
-    hydratedRewriteScopeRef.current = scope;
-    let disposed = false;
-
-    const updatePresentation = (
-      presentationId: string,
-      event: DocumentRewriteStreamEvent,
-    ) => {
-      if (!rewritePresentation) return;
-      switch (event.type) {
-        case "snapshot_fixed":
-          rewritePresentation.update(presentationId, {
-            stage: "requirements",
-            fileName: event.fileName || getFileName(filepath),
-            originalCharCount: event.originalCharCount,
-            requirementsPlan: "",
-          });
-          break;
-        case "requirements_started":
-          rewritePresentation.update(presentationId, { stage: "requirements", requirementsPlan: "" });
-          break;
-        case "requirements_checkpoint":
-        case "requirements_completed":
-          rewritePresentation.update(presentationId, {
-            stage: "requirements",
-            requirementsPlan: event.content,
-          });
-          break;
-        case "requirements_resolved":
-          rewritePresentation.update(presentationId, {
-            stage: "writing",
-            ...(event.plan ? { requirementsPlan: event.plan } : {}),
-          });
-          break;
-        case "rewrite_delta":
-          rewritePresentation.update(presentationId, {
-            stage: "writing",
-            writtenCharCount: event.charCount,
-          });
-          break;
-        case "illustration_started":
-          rewritePresentation.update(presentationId, {
-            stage: "illustrating",
-            illustrationTarget: event.section,
-            maxGeneratedImages: event.total || 1,
-          });
-          break;
-        case "illustration_generated":
-          rewritePresentation.update(presentationId, {
-            stage: "illustrating",
-            illustrationTarget: event.section,
-            generatedImageCount: event.generatedCount ?? event.position,
-            maxGeneratedImages: event.total || 1,
-          });
-          break;
-        case "illustration_completed":
-          rewritePresentation.update(presentationId, {
-            stage: "illustrating",
-            generatedImageCount: event.generatedCount,
-            maxGeneratedImages: event.requestedCount || 1,
-            warnings: event.warnings,
-          });
-          break;
-        case "validation_started":
-          rewritePresentation.update(presentationId, { stage: "validation" });
-          break;
-        case "validation_completed":
-          rewritePresentation.update(presentationId, { warnings: event.warnings });
-          break;
-        case "comparison_ready":
-          rewritePresentation.update(presentationId, { summary: event.summary });
-          break;
-        case "commit_started":
-          rewritePresentation.update(presentationId, { stage: "committing" });
-          break;
-        case "committed":
-          rewritePresentation.update(presentationId, {
-            rewrittenContent: event.content,
-            versionId: event.versionId ?? null,
-          });
-          break;
-        case "done":
-          rewritePresentation.update(presentationId, {
-            stage: "completed",
-            versionId: event.versionId ?? null,
-          });
-          break;
-        case "conflict":
-          rewritePresentation.update(presentationId, { stage: "conflict", error: event.message });
-          break;
-        case "cancelled":
-          rewritePresentation.update(presentationId, { stage: "cancelled", error: event.message });
-          break;
-        case "error":
-          rewritePresentation.update(presentationId, { stage: "error", error: event.message });
-          break;
-        default:
-          break;
-      }
-    };
-
-    void (async () => {
-      try {
-        const jobs = await listDurableDocumentRewrites({ threadId, path: filepath });
-        const latest = jobs[0];
-        if (disposed || !latest) return;
-        // Restore prior terminal rewrites into the ordinary message timeline in
-        // chronological order.  The newest job is handled below because it may
-        // still be active and needs its SSE stream resumed.
-        for (const historical of jobs.slice(1).reverse()) {
-          const historicalResult = historical.result;
-          const historicalSummary = historicalResult.summary && typeof historicalResult.summary === "object"
-            ? historicalResult.summary as DocumentRewriteSummary
-            : null;
-          const historicalPresentationId = rewritePresentation?.create({
-            threadId,
-            source: { kind: "artifact", id: threadId, path: filepath },
-            fileName: getFileName(filepath),
-            instruction: historical.request.instruction,
-            style: historical.request.style,
-            modelName: historical.request.modelName,
-            generateImages: historical.request.generateImages,
-            maxGeneratedImages: historical.request.maxGeneratedImages,
-            originalContent: historical.request.originalContent,
-            rewrittenContent: typeof historicalResult.content === "string" ? historicalResult.content : null,
-            requirementsPlan: typeof historicalResult.requirementsPlan === "string"
-              ? historicalResult.requirementsPlan
-              : "",
-          });
-          if (!historicalPresentationId || !rewritePresentation) continue;
-          rewritePresentation.update(historicalPresentationId, {
-            stage: historical.status === "completed"
-              ? historicalResult.status === "conflict" ? "conflict" : "completed"
-              : historical.status === "cancelled" ? "cancelled" : "error",
-            summary: historicalSummary,
-            warnings: historicalSummary?.validationWarnings ?? [],
-            versionId: typeof historicalResult.versionId === "string" ? historicalResult.versionId : null,
-            error: historicalResult.status === "conflict"
-              ? "文件在改写期间已变化，未覆盖原文件。"
-              : historical.status === "cancelled"
-                ? "已停止全文改写，原文件未被修改。"
-                : historical.status === "failed" ? "全文改写未完成，原文件未被修改。" : null,
-          });
-        }
-        const result = latest.result;
-        const summary = result.summary && typeof result.summary === "object"
-          ? result.summary as DocumentRewriteSummary
-          : null;
-        const originalContent = latest.request.originalContent || draftContent;
-        const rewrittenContent = typeof result.content === "string" ? result.content : null;
-        const presentationId = rewritePresentation?.create({
-          threadId,
-          source: { kind: "artifact", id: threadId, path: filepath },
-          fileName: getFileName(filepath),
-          instruction: latest.request.instruction,
-          style: latest.request.style,
-          modelName: latest.request.modelName,
-          generateImages: latest.request.generateImages,
-          maxGeneratedImages: latest.request.maxGeneratedImages,
-          originalContent,
-          rewrittenContent,
-          requirementsPlan: typeof result.requirementsPlan === "string" ? result.requirementsPlan : "",
-        });
-        if (!presentationId || !rewritePresentation) return;
-        setDocumentRewritePresentationId(presentationId);
-
-        if (latest.status === "completed") {
-          rewritePresentation.update(presentationId, {
-            stage: result.status === "conflict" ? "conflict" : "completed",
-            summary,
-            warnings: summary?.validationWarnings ?? [],
-            versionId: typeof result.versionId === "string" ? result.versionId : null,
-            error: result.status === "conflict" ? "文件在改写期间已变化，未覆盖原文件。" : null,
-          });
-          if (rewrittenContent && result.status !== "conflict") {
-            setDraftContent(rewrittenContent);
-            setHasLocalEdits(false);
-            queryClient.setQueriesData(
-              { queryKey: ["artifact", filepath, threadId, isMock] },
-              { content: rewrittenContent, url: undefined },
-            );
-          }
-          return;
-        }
-        if (latest.status === "failed" || latest.status === "cancelled") {
-          rewritePresentation.update(presentationId, {
-            stage: latest.status === "cancelled" ? "cancelled" : "error",
-            summary,
-          });
-          return;
-        }
-
-        void documentRewrite.start(
-          {
-            threadId,
-            path: filepath,
-            instruction: latest.request.instruction,
-            style: latest.request.style,
-            modelName: latest.request.modelName ?? undefined,
-            generateImages: latest.request.generateImages,
-            maxGeneratedImages: latest.request.maxGeneratedImages,
-          },
-          {
-            jobId: latest.id,
-            stream: (signal) => streamDurableDocumentRewriteJob(
-              { threadId, path: filepath },
-              latest.id,
-              signal,
-            ),
-            onEvent: (event) => updatePresentation(presentationId, event),
-            onCommitted: (rewritten) => {
-              setDraftContent(rewritten);
-              setHasLocalEdits(false);
-              rewritePresentation.update(presentationId, { rewrittenContent: rewritten });
-              queryClient.setQueriesData(
-                { queryKey: ["artifact", filepath, threadId, isMock] },
-                { content: rewritten, url: undefined },
-              );
-            },
-          },
-        );
-      } catch {
-        // Existing artifacts remain available even if history hydration fails.
-      }
-    })();
-    return () => {
-      disposed = true;
-    };
-  }, [
-    canEditArtifact,
-    documentRewrite,
-    documentRewriteActive,
-    draftContent,
-    filepath,
-    isMock,
-    queryClient,
-    rewritePresentation,
-    threadId,
-    useWriteFileStreaming,
-  ]);
-
-  // The stream hook already coalesces requirements tokens with rAF. Mirror the
-  // coalesced plan into the ordinary message-list card instead of forcing a
-  // React context write for every individual SSE delta.
-  useEffect(() => {
-    const presentationId = documentRewritePresentationId;
-    const plan = documentRewrite.run.requirementsPlan;
-    if (!presentationId || !rewritePresentation || !plan) {
-      return;
-    }
-
-    // `update` replaces the presentation context value, which changes the
-    // context object in this effect's dependency list.  Only write when this
-    // particular card actually receives new text; otherwise React would
-    // re-enter this effect indefinitely after each context update.
-    const previous = mirroredRequirementsPlanRef.current;
-    if (previous.presentationId === presentationId && previous.plan === plan) {
-      return;
-    }
-    mirroredRequirementsPlanRef.current = { presentationId, plan };
-    rewritePresentation.update(presentationId, {
-      requirementsPlan: plan,
-    });
-  }, [
-    documentRewrite.run.requirementsPlan,
-    documentRewritePresentationId,
-    rewritePresentation,
-  ]);
-
-  // Thoughts use the same rAF coalescing as the draft, then are mirrored once
-  // per browser frame into the regular message-list card. They never touch
-  // the artifact Markdown or the durable rewrite checkpoint.
-  useEffect(() => {
-    const presentationId = documentRewritePresentationId;
-    const thinking = documentRewrite.run.thinkingText;
-    if (!presentationId || !rewritePresentation || !thinking) return;
-    const previous = mirroredThinkingTextRef.current;
-    if (previous.presentationId === presentationId && previous.thinking === thinking) return;
-    mirroredThinkingTextRef.current = { presentationId, thinking };
-    rewritePresentation.update(presentationId, { thinkingText: thinking });
-  }, [documentRewrite.run.thinkingText, documentRewritePresentationId, rewritePresentation]);
-
-  useEffect(() => {
-    const handleRewriteUndo = (event: Event) => {
-      const detail = (event as CustomEvent<{
-        source?: { kind?: string; id?: string; path?: string };
-        content?: string;
-      }>).detail;
-      if (
-        detail?.source?.kind !== "artifact" ||
-        detail.source.id !== threadId ||
-        detail.source.path !== filepath ||
-        typeof detail.content !== "string"
-      ) {
-        return;
-      }
-      setDraftContent(detail.content);
-      setHasLocalEdits(false);
-      queryClient.setQueriesData(
-        { queryKey: ["artifact", filepath, threadId, isMock] },
-        { content: detail.content, url: undefined },
-      );
-    };
-    window.addEventListener(DOCUMENT_REWRITE_UNDONE_EVENT, handleRewriteUndo);
-    return () => window.removeEventListener(DOCUMENT_REWRITE_UNDONE_EVENT, handleRewriteUndo);
-  }, [filepath, isMock, queryClient, threadId]);
+  useEffect(() => {
+    if (!canEditArtifact || hasLocalEdits || documentRewriteActive) {
+      return;
+    }
+    setDraftContent(content ?? "");
+  }, [canEditArtifact, content, documentRewriteActive, hasLocalEdits]);
+
+  useEffect(() => {
+    if (
+      !canEditArtifact ||
+      !threadId ||
+      !filepath ||
+      isMock ||
+      useWriteFileStreaming ||
+      documentRewriteActive
+    ) {
+      return;
+    }
+    const scope = `${threadId}:${filepath}`;
+    if (hydratedRewriteScopeRef.current === scope) return;
+    hydratedRewriteScopeRef.current = scope;
+    let disposed = false;
+
+    const updatePresentation = (
+      presentationId: string,
+      event: DocumentRewriteStreamEvent,
+    ) => {
+      if (!rewritePresentation) return;
+      switch (event.type) {
+        case "snapshot_fixed":
+          rewritePresentation.update(presentationId, {
+            stage: "requirements",
+            fileName: event.fileName || getFileName(filepath),
+            originalCharCount: event.originalCharCount,
+            requirementsPlan: "",
+          });
+          break;
+        case "requirements_started":
+          rewritePresentation.update(presentationId, { stage: "requirements", requirementsPlan: "" });
+          break;
+        case "requirements_checkpoint":
+        case "requirements_completed":
+          rewritePresentation.update(presentationId, {
+            stage: "requirements",
+            requirementsPlan: event.content,
+          });
+          break;
+        case "requirements_resolved":
+          rewritePresentation.update(presentationId, {
+            stage: "writing",
+            ...(event.plan ? { requirementsPlan: event.plan } : {}),
+          });
+          break;
+        case "rewrite_delta":
+          rewritePresentation.update(presentationId, {
+            stage: "writing",
+            writtenCharCount: event.charCount,
+          });
+          break;
+        case "illustration_started":
+          rewritePresentation.update(presentationId, {
+            stage: "illustrating",
+            illustrationTarget: event.section,
+            maxGeneratedImages: event.total || 1,
+          });
+          break;
+        case "illustration_generated":
+          rewritePresentation.update(presentationId, {
+            stage: "illustrating",
+            illustrationTarget: event.section,
+            generatedImageCount: event.generatedCount ?? event.position,
+            maxGeneratedImages: event.total || 1,
+          });
+          break;
+        case "illustration_completed":
+          rewritePresentation.update(presentationId, {
+            stage: "illustrating",
+            generatedImageCount: event.generatedCount,
+            maxGeneratedImages: event.requestedCount || 1,
+            warnings: event.warnings,
+          });
+          break;
+        case "validation_started":
+          rewritePresentation.update(presentationId, { stage: "validation" });
+          break;
+        case "validation_completed":
+          rewritePresentation.update(presentationId, { warnings: event.warnings });
+          break;
+        case "comparison_ready":
+          rewritePresentation.update(presentationId, { summary: event.summary });
+          break;
+        case "commit_started":
+          rewritePresentation.update(presentationId, { stage: "committing" });
+          break;
+        case "committed":
+          rewritePresentation.update(presentationId, {
+            rewrittenContent: event.content,
+            versionId: event.versionId ?? null,
+          });
+          break;
+        case "done":
+          rewritePresentation.update(presentationId, {
+            stage: "completed",
+            versionId: event.versionId ?? null,
+          });
+          break;
+        case "conflict":
+          rewritePresentation.update(presentationId, { stage: "conflict", error: event.message });
+          break;
+        case "cancelled":
+          rewritePresentation.update(presentationId, { stage: "cancelled", error: event.message });
+          break;
+        case "error":
+          rewritePresentation.update(presentationId, { stage: "error", error: event.message });
+          break;
+        default:
+          break;
+      }
+    };
+
+    void (async () => {
+      try {
+        const jobs = await listDurableDocumentRewrites({ threadId, path: filepath });
+        const latest = jobs[0];
+        if (disposed || !latest) return;
+        // Restore prior terminal rewrites into the ordinary message timeline in
+        // chronological order.  The newest job is handled below because it may
+        // still be active and needs its SSE stream resumed.
+        for (const historical of jobs.slice(1).reverse()) {
+          const historicalResult = historical.result;
+          const historicalSummary = historicalResult.summary && typeof historicalResult.summary === "object"
+            ? historicalResult.summary as DocumentRewriteSummary
+            : null;
+          const historicalPresentationId = rewritePresentation?.create({
+            threadId,
+            source: { kind: "artifact", id: threadId, path: filepath },
+            fileName: getFileName(filepath),
+            instruction: historical.request.instruction,
+            style: historical.request.style,
+            modelName: historical.request.modelName,
+            generateImages: historical.request.generateImages,
+            maxGeneratedImages: historical.request.maxGeneratedImages,
+            originalContent: historical.request.originalContent,
+            rewrittenContent: typeof historicalResult.content === "string" ? historicalResult.content : null,
+            requirementsPlan: typeof historicalResult.requirementsPlan === "string"
+              ? historicalResult.requirementsPlan
+              : "",
+          });
+          if (!historicalPresentationId || !rewritePresentation) continue;
+          rewritePresentation.update(historicalPresentationId, {
+            stage: historical.status === "completed"
+              ? historicalResult.status === "conflict" ? "conflict" : "completed"
+              : historical.status === "cancelled" ? "cancelled" : "error",
+            summary: historicalSummary,
+            warnings: historicalSummary?.validationWarnings ?? [],
+            versionId: typeof historicalResult.versionId === "string" ? historicalResult.versionId : null,
+            error: historicalResult.status === "conflict"
+              ? "文件在改写期间已变化，未覆盖原文件。"
+              : historical.status === "cancelled"
+                ? "已停止全文改写，原文件未被修改。"
+                : historical.status === "failed" ? "全文改写未完成，原文件未被修改。" : null,
+          });
+        }
+        const result = latest.result;
+        const summary = result.summary && typeof result.summary === "object"
+          ? result.summary as DocumentRewriteSummary
+          : null;
+        const originalContent = latest.request.originalContent || draftContent;
+        const rewrittenContent = typeof result.content === "string" ? result.content : null;
+        const presentationId = rewritePresentation?.create({
+          threadId,
+          source: { kind: "artifact", id: threadId, path: filepath },
+          fileName: getFileName(filepath),
+          instruction: latest.request.instruction,
+          style: latest.request.style,
+          modelName: latest.request.modelName,
+          generateImages: latest.request.generateImages,
+          maxGeneratedImages: latest.request.maxGeneratedImages,
+          originalContent,
+          rewrittenContent,
+          requirementsPlan: typeof result.requirementsPlan === "string" ? result.requirementsPlan : "",
+        });
+        if (!presentationId || !rewritePresentation) return;
+        setDocumentRewritePresentationId(presentationId);
+
+        if (latest.status === "completed") {
+          rewritePresentation.update(presentationId, {
+            stage: result.status === "conflict" ? "conflict" : "completed",
+            summary,
+            warnings: summary?.validationWarnings ?? [],
+            versionId: typeof result.versionId === "string" ? result.versionId : null,
+            error: result.status === "conflict" ? "文件在改写期间已变化，未覆盖原文件。" : null,
+          });
+          if (rewrittenContent && result.status !== "conflict") {
+            setDraftContent(rewrittenContent);
+            setHasLocalEdits(false);
+            queryClient.setQueriesData(
+              { queryKey: ["artifact", filepath, threadId, isMock] },
+              { content: rewrittenContent, url: undefined },
+            );
+          }
+          return;
+        }
+        if (latest.status === "failed" || latest.status === "cancelled") {
+          rewritePresentation.update(presentationId, {
+            stage: latest.status === "cancelled" ? "cancelled" : "error",
+            summary,
+          });
+          return;
+        }
+
+        void documentRewrite.start(
+          {
+            threadId,
+            path: filepath,
+            instruction: latest.request.instruction,
+            style: latest.request.style,
+            modelName: latest.request.modelName ?? undefined,
+            generateImages: latest.request.generateImages,
+            maxGeneratedImages: latest.request.maxGeneratedImages,
+          },
+          {
+            jobId: latest.id,
+            stream: (signal) => streamDurableDocumentRewriteJob(
+              { threadId, path: filepath },
+              latest.id,
+              signal,
+            ),
+            onEvent: (event) => updatePresentation(presentationId, event),
+            onCommitted: (rewritten) => {
+              setDraftContent(rewritten);
+              setHasLocalEdits(false);
+              rewritePresentation.update(presentationId, { rewrittenContent: rewritten });
+              queryClient.setQueriesData(
+                { queryKey: ["artifact", filepath, threadId, isMock] },
+                { content: rewritten, url: undefined },
+              );
+            },
+          },
+        );
+      } catch {
+        // Existing artifacts remain available even if history hydration fails.
+      }
+    })();
+    return () => {
+      disposed = true;
+    };
+  }, [
+    canEditArtifact,
+    documentRewrite,
+    documentRewriteActive,
+    draftContent,
+    filepath,
+    isMock,
+    queryClient,
+    rewritePresentation,
+    threadId,
+    useWriteFileStreaming,
+  ]);
+
+  // The stream hook already coalesces requirements tokens with rAF. Mirror the
+  // coalesced plan into the ordinary message-list card instead of forcing a
+  // React context write for every individual SSE delta.
+  useEffect(() => {
+    const presentationId = documentRewritePresentationId;
+    const plan = documentRewrite.run.requirementsPlan;
+    if (!presentationId || !rewritePresentation || !plan) {
+      return;
+    }
+
+    // `update` replaces the presentation context value, which changes the
+    // context object in this effect's dependency list.  Only write when this
+    // particular card actually receives new text; otherwise React would
+    // re-enter this effect indefinitely after each context update.
+    const previous = mirroredRequirementsPlanRef.current;
+    if (previous.presentationId === presentationId && previous.plan === plan) {
+      return;
+    }
+    mirroredRequirementsPlanRef.current = { presentationId, plan };
+    rewritePresentation.update(presentationId, {
+      requirementsPlan: plan,
+    });
+  }, [
+    documentRewrite.run.requirementsPlan,
+    documentRewritePresentationId,
+    rewritePresentation,
+  ]);
+
+  // Thoughts use the same rAF coalescing as the draft, then are mirrored once
+  // per browser frame into the regular message-list card. They never touch
+  // the artifact Markdown or the durable rewrite checkpoint.
+  useEffect(() => {
+    const presentationId = documentRewritePresentationId;
+    const thinking = documentRewrite.run.thinkingText;
+    if (!presentationId || !rewritePresentation || !thinking) return;
+    const previous = mirroredThinkingTextRef.current;
+    if (previous.presentationId === presentationId && previous.thinking === thinking) return;
+    mirroredThinkingTextRef.current = { presentationId, thinking };
+    rewritePresentation.update(presentationId, { thinkingText: thinking });
+  }, [documentRewrite.run.thinkingText, documentRewritePresentationId, rewritePresentation]);
+
+  useEffect(() => {
+    const handleRewriteUndo = (event: Event) => {
+      const detail = (event as CustomEvent<{
+        source?: { kind?: string; id?: string; path?: string };
+        content?: string;
+      }>).detail;
+      if (
+        detail?.source?.kind !== "artifact" ||
+        detail.source.id !== threadId ||
+        detail.source.path !== filepath ||
+        typeof detail.content !== "string"
+      ) {
+        return;
+      }
+      setDraftContent(detail.content);
+      setHasLocalEdits(false);
+      queryClient.setQueriesData(
+        { queryKey: ["artifact", filepath, threadId, isMock] },
+        { content: detail.content, url: undefined },
+      );
+    };
+    window.addEventListener(DOCUMENT_REWRITE_UNDONE_EVENT, handleRewriteUndo);
+    return () => window.removeEventListener(DOCUMENT_REWRITE_UNDONE_EVENT, handleRewriteUndo);
+  }, [filepath, isMock, queryClient, threadId]);
 
   useEffect(() => {
     setAllowAutoViewSwitch(true);
@@ -760,10 +761,10 @@ export function ArtifactFileDetail({
     [],
   );
 
-  useEffect(() => {
-    if (!(thread.isLoading || documentRewriteActive) || !autoScrollEnabled) {
-      return;
-    }
+  useEffect(() => {
+    if (!(thread.isLoading || documentRewriteActive) || !autoScrollEnabled) {
+      return;
+    }
 
     const tick = () => {
       scrollArtifactToBottom("auto");
@@ -772,26 +773,26 @@ export function ArtifactFileDetail({
     tick();
     const intervalId = window.setInterval(tick, 180);
     return () => window.clearInterval(intervalId);
-  }, [
-    autoScrollEnabled,
-    documentRewriteActive,
-    scrollArtifactToBottom,
-    thread.isLoading,
-  ]);
-
-  useEffect(() => {
-    if (!(thread.isLoading || documentRewriteActive) || !autoScrollEnabled) {
-      return;
-    }
+  }, [
+    autoScrollEnabled,
+    documentRewriteActive,
+    scrollArtifactToBottom,
+    thread.isLoading,
+  ]);
+
+  useEffect(() => {
+    if (!(thread.isLoading || documentRewriteActive) || !autoScrollEnabled) {
+      return;
+    }
 
     scrollArtifactToBottom("auto");
   }, [
     autoScrollEnabled,
-    displayContent,
-    documentRewriteActive,
-    scrollArtifactToBottom,
-    thread.isLoading,
-    viewMode,
+    displayContent,
+    documentRewriteActive,
+    scrollArtifactToBottom,
+    thread.isLoading,
+    viewMode,
   ]);
 
   useEffect(() => {
@@ -816,7 +817,7 @@ export function ArtifactFileDetail({
   }, []);
 
   useEffect(() => {
-    if (isCodeFile) {
+    if (isCodeFile || isWriteFileVirtual || !isArtifactApiPath(filepath)) {
       setSpreadsheetData(null);
       setBinaryPreviewUrl((prev) => {
         if (prev) URL.revokeObjectURL(prev);
@@ -863,7 +864,7 @@ export function ArtifactFileDetail({
         return null;
       });
     };
-  }, [filepath, threadId, isMock, isCodeFile, isSpreadsheetFile, publicShareCode]);
+  }, [filepath, threadId, isMock, isCodeFile, isSpreadsheetFile, isWriteFileVirtual, publicShareCode]);
 
   const handlePauseAutoScroll = useCallback(() => {
     if (!thread.isLoading || !autoScrollEnabled) {
@@ -888,8 +889,8 @@ export function ArtifactFileDetail({
     }, 1600);
   }, [scrollArtifactToBottom]);
 
-  const handleSaveArtifact = useCallback(async () => {
-    if (!canEditArtifact || updateArtifact.isPending || documentRewriteActive) {
+  const handleSaveArtifact = useCallback(async () => {
+    if (!canEditArtifact || updateArtifact.isPending || documentRewriteActive) {
       return;
     }
     try {
@@ -911,192 +912,192 @@ export function ArtifactFileDetail({
     filepath,
     isMock,
     threadId,
-    updateArtifact,
-    documentRewriteActive,
-  ]);
-
-  const handleStartDocumentRewrite = useCallback(
-    async (input: {
-      instruction: string;
-      style: "formal_analysis" | "professional" | "concise" | "readable";
-      modelName: string | null;
-      generateImages: boolean;
-      maxGeneratedImages: number;
-    }) => {
-      if (!canUseFullDocumentRewrite) {
-        toast.error(
-          hasLocalEdits
-            ? "请先保存当前 Markdown 修改后再进行全文改写。"
-            : "当前文件暂不支持全文改写。",
-        );
-        return;
-      }
-      setDocumentRewriteDialogOpen(false);
-      setAllowAutoViewSwitch(false);
-      setAutoScrollEnabled(true);
-      setViewMode("code");
-      const expectedHash = await sha256Content(draftContent);
-      const presentationId = rewritePresentation?.create({
-        threadId,
-        source: { kind: "artifact", id: threadId, path: filepath },
-        fileName: getFileName(filepath),
-        instruction: input.instruction,
-        style: input.style,
-        modelName: input.modelName,
-        generateImages: input.generateImages,
-        maxGeneratedImages: input.maxGeneratedImages,
-        originalContent: draftContent,
-      });
-      setDocumentRewritePresentationId(presentationId ?? null);
-      void documentRewrite.start(
-        {
-          threadId,
-          path: filepath,
-          instruction: input.instruction,
-          style: input.style,
-          modelName: input.modelName ?? undefined,
-          generateImages: input.generateImages,
-          maxGeneratedImages: input.maxGeneratedImages,
-          expectedHash,
-        },
-        {
-          onEvent: (event) => {
-            if (!presentationId || !rewritePresentation) return;
-            switch (event.type) {
-              case "snapshot_fixed":
-                rewritePresentation.update(presentationId, {
-                  stage: "requirements",
-                  fileName: event.fileName || getFileName(filepath),
-                  originalCharCount: event.originalCharCount,
-                  requirementsPlan: "",
-                });
-                break;
-              case "requirements_started":
-                rewritePresentation.update(presentationId, {
-                  stage: "requirements",
-                  requirementsPlan: "",
-                });
-                break;
-              case "requirements_checkpoint":
-              case "requirements_completed":
-                rewritePresentation.update(presentationId, {
-                  stage: "requirements",
-                  requirementsPlan: event.content,
-                });
-                break;
-              case "requirements_resolved":
-                rewritePresentation.update(presentationId, {
-                  stage: "writing",
-                  ...(event.plan ? { requirementsPlan: event.plan } : {}),
-                });
-                break;
-              case "rewrite_delta":
-                rewritePresentation.update(presentationId, {
-                  stage: "writing",
-                  writtenCharCount: event.charCount,
-                });
-                break;
-              case "illustration_started":
-                rewritePresentation.update(presentationId, {
-                  stage: "illustrating",
-                  illustrationTarget: event.section,
-                  maxGeneratedImages: event.total || 1,
-                });
-                break;
-              case "illustration_generated":
-                rewritePresentation.update(presentationId, {
-                  stage: "illustrating",
-                  illustrationTarget: event.section,
-                  generatedImageCount: event.generatedCount ?? event.position,
-                  maxGeneratedImages: event.total || 1,
-                });
-                break;
-              case "illustration_completed":
-                rewritePresentation.update(presentationId, {
-                  stage: "illustrating",
-                  generatedImageCount: event.generatedCount,
-                  maxGeneratedImages: event.requestedCount || 1,
-                  warnings: event.warnings,
-                });
-                break;
-              case "validation_started":
-                rewritePresentation.update(presentationId, { stage: "validation" });
-                break;
-              case "validation_completed":
-                rewritePresentation.update(presentationId, { warnings: event.warnings });
-                break;
-              case "comparison_ready":
-                rewritePresentation.update(presentationId, { summary: event.summary });
-                break;
-              case "commit_started":
-                rewritePresentation.update(presentationId, { stage: "committing" });
-                break;
-              case "committed":
-                rewritePresentation.update(presentationId, {
-                  versionId: event.versionId ?? null,
-                });
-                break;
-              case "done":
-                rewritePresentation.update(presentationId, {
-                  stage: "completed",
-                  versionId: event.versionId ?? null,
-                });
-                break;
-              case "conflict":
-                rewritePresentation.update(presentationId, {
-                  stage: "conflict",
-                  error: event.message,
-                });
-                break;
-              case "error":
-                rewritePresentation.update(presentationId, {
-                  stage: "error",
-                  error: event.message,
-                });
-                break;
-              default:
-                break;
-            }
-          },
-          onCommitted: (rewritten) => {
-            setDraftContent(rewritten);
-            setHasLocalEdits(false);
-            if (presentationId && rewritePresentation) {
-              rewritePresentation.update(presentationId, { rewrittenContent: rewritten });
-            }
-            queryClient.setQueriesData(
-              {
-                queryKey: ["artifact", filepath, threadId, isMock],
-              },
-              { content: rewritten, url: undefined },
-            );
-            toast.success("Markdown 全文改写完成，已安全替换原文件。");
-          },
-        },
-      );
-    },
-    [
-      canUseFullDocumentRewrite,
-      draftContent,
-      documentRewrite,
-      filepath,
-      hasLocalEdits,
-      isMock,
-      queryClient,
-      rewritePresentation,
-      threadId,
-    ],
-  );
-
-  const handleCancelDocumentRewrite = useCallback(() => {
-    documentRewrite.cancel();
-    if (documentRewritePresentationId && rewritePresentation) {
-      rewritePresentation.update(documentRewritePresentationId, {
-        stage: "cancelled",
-        error: "已停止全文改写，原文件未被修改。",
-      });
-    }
-  }, [documentRewrite, documentRewritePresentationId, rewritePresentation]);
+    updateArtifact,
+    documentRewriteActive,
+  ]);
+
+  const handleStartDocumentRewrite = useCallback(
+    async (input: {
+      instruction: string;
+      style: "formal_analysis" | "professional" | "concise" | "readable";
+      modelName: string | null;
+      generateImages: boolean;
+      maxGeneratedImages: number;
+    }) => {
+      if (!canUseFullDocumentRewrite) {
+        toast.error(
+          hasLocalEdits
+            ? "请先保存当前 Markdown 修改后再进行全文改写。"
+            : "当前文件暂不支持全文改写。",
+        );
+        return;
+      }
+      setDocumentRewriteDialogOpen(false);
+      setAllowAutoViewSwitch(false);
+      setAutoScrollEnabled(true);
+      setViewMode("code");
+      const expectedHash = await sha256Content(draftContent);
+      const presentationId = rewritePresentation?.create({
+        threadId,
+        source: { kind: "artifact", id: threadId, path: filepath },
+        fileName: getFileName(filepath),
+        instruction: input.instruction,
+        style: input.style,
+        modelName: input.modelName,
+        generateImages: input.generateImages,
+        maxGeneratedImages: input.maxGeneratedImages,
+        originalContent: draftContent,
+      });
+      setDocumentRewritePresentationId(presentationId ?? null);
+      void documentRewrite.start(
+        {
+          threadId,
+          path: filepath,
+          instruction: input.instruction,
+          style: input.style,
+          modelName: input.modelName ?? undefined,
+          generateImages: input.generateImages,
+          maxGeneratedImages: input.maxGeneratedImages,
+          expectedHash,
+        },
+        {
+          onEvent: (event) => {
+            if (!presentationId || !rewritePresentation) return;
+            switch (event.type) {
+              case "snapshot_fixed":
+                rewritePresentation.update(presentationId, {
+                  stage: "requirements",
+                  fileName: event.fileName || getFileName(filepath),
+                  originalCharCount: event.originalCharCount,
+                  requirementsPlan: "",
+                });
+                break;
+              case "requirements_started":
+                rewritePresentation.update(presentationId, {
+                  stage: "requirements",
+                  requirementsPlan: "",
+                });
+                break;
+              case "requirements_checkpoint":
+              case "requirements_completed":
+                rewritePresentation.update(presentationId, {
+                  stage: "requirements",
+                  requirementsPlan: event.content,
+                });
+                break;
+              case "requirements_resolved":
+                rewritePresentation.update(presentationId, {
+                  stage: "writing",
+                  ...(event.plan ? { requirementsPlan: event.plan } : {}),
+                });
+                break;
+              case "rewrite_delta":
+                rewritePresentation.update(presentationId, {
+                  stage: "writing",
+                  writtenCharCount: event.charCount,
+                });
+                break;
+              case "illustration_started":
+                rewritePresentation.update(presentationId, {
+                  stage: "illustrating",
+                  illustrationTarget: event.section,
+                  maxGeneratedImages: event.total || 1,
+                });
+                break;
+              case "illustration_generated":
+                rewritePresentation.update(presentationId, {
+                  stage: "illustrating",
+                  illustrationTarget: event.section,
+                  generatedImageCount: event.generatedCount ?? event.position,
+                  maxGeneratedImages: event.total || 1,
+                });
+                break;
+              case "illustration_completed":
+                rewritePresentation.update(presentationId, {
+                  stage: "illustrating",
+                  generatedImageCount: event.generatedCount,
+                  maxGeneratedImages: event.requestedCount || 1,
+                  warnings: event.warnings,
+                });
+                break;
+              case "validation_started":
+                rewritePresentation.update(presentationId, { stage: "validation" });
+                break;
+              case "validation_completed":
+                rewritePresentation.update(presentationId, { warnings: event.warnings });
+                break;
+              case "comparison_ready":
+                rewritePresentation.update(presentationId, { summary: event.summary });
+                break;
+              case "commit_started":
+                rewritePresentation.update(presentationId, { stage: "committing" });
+                break;
+              case "committed":
+                rewritePresentation.update(presentationId, {
+                  versionId: event.versionId ?? null,
+                });
+                break;
+              case "done":
+                rewritePresentation.update(presentationId, {
+                  stage: "completed",
+                  versionId: event.versionId ?? null,
+                });
+                break;
+              case "conflict":
+                rewritePresentation.update(presentationId, {
+                  stage: "conflict",
+                  error: event.message,
+                });
+                break;
+              case "error":
+                rewritePresentation.update(presentationId, {
+                  stage: "error",
+                  error: event.message,
+                });
+                break;
+              default:
+                break;
+            }
+          },
+          onCommitted: (rewritten) => {
+            setDraftContent(rewritten);
+            setHasLocalEdits(false);
+            if (presentationId && rewritePresentation) {
+              rewritePresentation.update(presentationId, { rewrittenContent: rewritten });
+            }
+            queryClient.setQueriesData(
+              {
+                queryKey: ["artifact", filepath, threadId, isMock],
+              },
+              { content: rewritten, url: undefined },
+            );
+            toast.success("Markdown 全文改写完成，已安全替换原文件。");
+          },
+        },
+      );
+    },
+    [
+      canUseFullDocumentRewrite,
+      draftContent,
+      documentRewrite,
+      filepath,
+      hasLocalEdits,
+      isMock,
+      queryClient,
+      rewritePresentation,
+      threadId,
+    ],
+  );
+
+  const handleCancelDocumentRewrite = useCallback(() => {
+    documentRewrite.cancel();
+    if (documentRewritePresentationId && rewritePresentation) {
+      rewritePresentation.update(documentRewritePresentationId, {
+        stage: "cancelled",
+        error: "已停止全文改写，原文件未被修改。",
+      });
+    }
+  }, [documentRewrite, documentRewritePresentationId, rewritePresentation]);
 
   // 发布入库：仅当当前路由是智能体会话（agents/:agent_id/chats/…）且该智能体
   // 配置了入库模板名（template_name）时，md 产物右上角才出现发布按钮。
@@ -1211,18 +1212,18 @@ export function ArtifactFileDetail({
     <Artifact className={cn(className)}>
       <ArtifactHeader className="flex flex-wrap items-center gap-3 px-4 py-3">
         <div className="flex min-w-0 items-center gap-2">
-          <div
-            className={cn(
-              "inline-flex min-w-0 items-center gap-2",
-              !headerLeadingActionBare &&
-                "bg-muted/65 rounded-full border border-black/6 p-1 shadow-sm dark:border-white/8",
-            )}
-          >
-            {headerLeadingAction ?? (
-              <span className="bg-background text-muted-foreground inline-flex h-7 shrink-0 items-center rounded-full border border-black/6 px-2.5 text-[10px] font-semibold tracking-[0.16em] dark:border-white/8">
-                {fileTypeLabel}
-              </span>
-            )}
+          <div
+            className={cn(
+              "inline-flex min-w-0 items-center gap-2",
+              !headerLeadingActionBare &&
+                "bg-muted/65 rounded-full border border-black/6 p-1 shadow-sm dark:border-white/8",
+            )}
+          >
+            {headerLeadingAction ?? (
+              <span className="bg-background text-muted-foreground inline-flex h-7 shrink-0 items-center rounded-full border border-black/6 px-2.5 text-[10px] font-semibold tracking-[0.16em] dark:border-white/8">
+                {fileTypeLabel}
+              </span>
+            )}
             {!hideFileName && (
             <ArtifactTitle className="min-w-0">
               {/* markdown：隐藏文件名（仅留 MD 徽标），把横向空间让给工具栏，避免窄面板下
@@ -1272,7 +1273,7 @@ export function ArtifactFileDetail({
                   }
                 }}
               >
-                {canUseAiEditor && !documentRewriteActive && (
+                {canUseAiEditor && !documentRewriteActive && (
                   <ToggleGroupItem
                     className="text-muted-foreground h-8 min-w-10 rounded-full border-0 bg-transparent px-3 shadow-none data-[state=on]:bg-background data-[state=on]:text-foreground data-[state=on]:shadow-[0_6px_14px_-10px_rgba(15,23,42,0.35)]"
                     value="edit"
@@ -1314,31 +1315,31 @@ export function ArtifactFileDetail({
                 onClick={() => void handlePublishToKnowledge()}
               />
             )}
-            {canEditArtifact && (
-              <ArtifactAction
-                icon={updateArtifact.isPending ? LoaderIcon : SaveIcon}
-                label="保存 Markdown"
-                tooltip={hasLocalEdits ? "保存 Markdown 修改" : "Markdown 已保存"}
-                disabled={!hasLocalEdits || updateArtifact.isPending || documentRewriteActive}
-                onClick={handleSaveArtifact}
-              />
-            )}
-            {toolbarActions}
-            {canEditArtifact && (
-              <ArtifactAction
-                icon={documentRewriteActive ? LoaderIcon : SparklesIcon}
-                label={documentRewriteActive ? "正在全文改写" : "AI 全文改写"}
-                tooltip={
-                  documentRewriteActive
-                    ? "正在生成临时草稿，原文件尚未被覆盖"
-                    : hasLocalEdits
-                      ? "请先保存当前 Markdown 修改"
-                      : "使用 AI 重写当前完整 Markdown"
-                }
-                disabled={documentRewriteActive || !canUseFullDocumentRewrite}
-                onClick={() => setDocumentRewriteDialogOpen(true)}
-              />
-            )}
+            {canEditArtifact && (
+              <ArtifactAction
+                icon={updateArtifact.isPending ? LoaderIcon : SaveIcon}
+                label="保存 Markdown"
+                tooltip={hasLocalEdits ? "保存 Markdown 修改" : "Markdown 已保存"}
+                disabled={!hasLocalEdits || updateArtifact.isPending || documentRewriteActive}
+                onClick={handleSaveArtifact}
+              />
+            )}
+            {toolbarActions}
+            {canEditArtifact && (
+              <ArtifactAction
+                icon={documentRewriteActive ? LoaderIcon : SparklesIcon}
+                label={documentRewriteActive ? "正在全文改写" : "AI 全文改写"}
+                tooltip={
+                  documentRewriteActive
+                    ? "正在生成临时草稿，原文件尚未被覆盖"
+                    : hasLocalEdits
+                      ? "请先保存当前 Markdown 修改"
+                      : "使用 AI 重写当前完整 Markdown"
+                }
+                disabled={documentRewriteActive || !canUseFullDocumentRewrite}
+                onClick={() => setDocumentRewriteDialogOpen(true)}
+              />
+            )}
             {!useWriteFileStreaming && filepath.endsWith(".skill") && (
               <Tooltip content={t.toolCalls.skillInstallTooltip}>
                 <ArtifactAction
@@ -1445,33 +1446,33 @@ export function ArtifactFileDetail({
         className="relative p-0"
         onWheelCapture={handlePauseAutoScroll}
       >
-        {isApplyingEdit && (
+        {isApplyingEdit && (
           <div className="absolute right-4 bottom-4 z-20 inline-flex items-center gap-2 rounded-full border border-[#d8b878] bg-[#fff3cf]/95 px-3 py-1.5 text-xs text-[#6d5625] shadow-sm">
             <span className="h-3.5 w-0.5 animate-pulse rounded-full bg-[#9b7a2f]" />
             正在改写 Markdown
           </div>
-        )}
-        {documentRewriteActive && (
-          <div className="absolute right-4 bottom-4 z-20 inline-flex items-center gap-2 rounded-full border border-[#d8b878] bg-[#fff3cf]/95 px-3 py-1.5 text-xs text-[#6d5625] shadow-sm">
-            <LoaderIcon className="size-3.5 animate-spin" />
-            {documentRewrite.run.stage === "requirements"
-              ? "正在理解改写需求，原文件未被修改"
-              : documentRewrite.run.stage === "validation"
-              ? "正在校验 Markdown"
-              : documentRewrite.run.stage === "committing"
-                ? "正在安全替换原文件"
-                : "正在写入临时草稿 · " +
-                  documentRewrite.run.writtenCharCount.toLocaleString() +
-                  " 字"}
-            <button
-              type="button"
-              className="ml-1 rounded px-1.5 py-0.5 font-medium hover:bg-[#ead9a6]"
-              onClick={handleCancelDocumentRewrite}
-            >
-              停止
-            </button>
-          </div>
-        )}
+        )}
+        {documentRewriteActive && (
+          <div className="absolute right-4 bottom-4 z-20 inline-flex items-center gap-2 rounded-full border border-[#d8b878] bg-[#fff3cf]/95 px-3 py-1.5 text-xs text-[#6d5625] shadow-sm">
+            <LoaderIcon className="size-3.5 animate-spin" />
+            {documentRewrite.run.stage === "requirements"
+              ? "正在理解改写需求，原文件未被修改"
+              : documentRewrite.run.stage === "validation"
+              ? "正在校验 Markdown"
+              : documentRewrite.run.stage === "committing"
+                ? "正在安全替换原文件"
+                : "正在写入临时草稿 · " +
+                  documentRewrite.run.writtenCharCount.toLocaleString() +
+                  " 字"}
+            <button
+              type="button"
+              className="ml-1 rounded px-1.5 py-0.5 font-medium hover:bg-[#ead9a6]"
+              onClick={handleCancelDocumentRewrite}
+            >
+              停止
+            </button>
+          </div>
+        )}
         {showResumeAutoScroll && (
           <button
             type="button"
@@ -1482,7 +1483,7 @@ export function ArtifactFileDetail({
             滑动到底部并继续自动下滑
           </button>
         )}
-        {viewMode === "edit" && canUseAiEditor && !documentRewriteActive && (
+        {viewMode === "edit" && canUseAiEditor && !documentRewriteActive && (
           <MarkdownAiEditor
             // 编辑用原始内容（与源码模式一致，不脱敏）；保存仍走头部「保存 Markdown」按钮。
             markdown={displayContent ?? ""}
@@ -1501,10 +1502,10 @@ export function ArtifactFileDetail({
               <ArtifactFilePreview
                 content={disableDesensitize ? (displayContent ?? "") : desensitize(displayContent ?? "")}
                 language={language ?? "text"}
-                threadId={threadId}
-                publicShareCode={publicShareCode}
-                researchSessionId={researchSessionId}
-                animated={showPreviewSwitchPulse}
+                threadId={threadId}
+                publicShareCode={publicShareCode}
+                researchSessionId={researchSessionId}
+                animated={showPreviewSwitchPulse}
                 activeCursor={isApplyingEdit}
               />
             )}
@@ -1517,9 +1518,9 @@ export function ArtifactFileDetail({
                   ? (displayContent ?? "")
                   : desensitize(displayContent ?? "")
               }
-              readonly={!canEditArtifact || documentRewriteActive}
-              onChange={
-                canEditArtifact && !documentRewriteActive
+              readonly={!canEditArtifact || documentRewriteActive}
+              onChange={
+                canEditArtifact && !documentRewriteActive
                   ? (value) => {
                       setDraftContent(value);
                       setHasLocalEdits(true);
@@ -1551,51 +1552,51 @@ export function ArtifactFileDetail({
             </div>
           ))}
       </ArtifactContent>
-      <SkillInstallDialog
+      <SkillInstallDialog
         open={installDialogOpen}
         onOpenChange={setInstallDialogOpen}
         threadId={threadId}
-        filepath={filepath}
-      />
-      <DocumentRewriteDialog
-        open={documentRewriteDialogOpen}
-        onOpenChange={setDocumentRewriteDialogOpen}
-        fileName={getFileName(filepath)}
-        charCount={(displayContent ?? "").replace(/\s/g, "").length}
-        imageGenerationAvailable={imageGenerationAvailable}
-        maxGeneratedImages={maxGeneratedImages}
-        onStart={handleStartDocumentRewrite}
-      />
-    </Artifact>
+        filepath={filepath}
+      />
+      <DocumentRewriteDialog
+        open={documentRewriteDialogOpen}
+        onOpenChange={setDocumentRewriteDialogOpen}
+        fileName={getFileName(filepath)}
+        charCount={(displayContent ?? "").replace(/\s/g, "").length}
+        imageGenerationAvailable={imageGenerationAvailable}
+        maxGeneratedImages={maxGeneratedImages}
+        onStart={handleStartDocumentRewrite}
+      />
+    </Artifact>
   );
 }
 
-function SandboxPreviewImage({
-  src,
-  alt,
-  threadId,
-  publicShareCode,
-  researchSessionId,
-  ...props
-}: React.ImgHTMLAttributes<HTMLImageElement> & {
-  threadId: string;
-  publicShareCode?: string;
-  researchSessionId?: string;
-}) {
-  if (!src || typeof src !== "string") {
-    return null;
-  }
-
-  if (src.startsWith("deep-research://")) {
-    return researchSessionId ? (
-      <ProtectedResearchReportImage
-        {...props}
-        alt={alt}
-        sessionId={researchSessionId}
-        src={src}
-      />
-    ) : null;
-  }
+function SandboxPreviewImage({
+  src,
+  alt,
+  threadId,
+  publicShareCode,
+  researchSessionId,
+  ...props
+}: React.ImgHTMLAttributes<HTMLImageElement> & {
+  threadId: string;
+  publicShareCode?: string;
+  researchSessionId?: string;
+}) {
+  if (!src || typeof src !== "string") {
+    return null;
+  }
+
+  if (src.startsWith("deep-research://")) {
+    return researchSessionId ? (
+      <ProtectedResearchReportImage
+        {...props}
+        alt={alt}
+        sessionId={researchSessionId}
+        src={src}
+      />
+    ) : null;
+  }
 
   let url = src;
   if (src.startsWith("/mnt/")) {
@@ -1619,108 +1620,108 @@ function SandboxPreviewImage({
       src={url}
       alt={alt}
     />
-  );
-}
-
-/** Fetches a private deep-research image with the normal auth client. */
-function ProtectedResearchReportImage({
-  sessionId,
-  src,
-  alt,
-  ...props
-}: React.ImgHTMLAttributes<HTMLImageElement> & {
-  sessionId: string;
-}) {
-  const [objectUrl, setObjectUrl] = useState<string | null>(null);
-  const [loadFailed, setLoadFailed] = useState(false);
-  const [retryKey, setRetryKey] = useState(0);
-
-  useEffect(() => {
-    setObjectUrl(null);
-    setLoadFailed(false);
-    if (!src?.startsWith("deep-research://")) {
-      return;
-    }
-    const name = src.slice("deep-research://".length);
-    if (!name) {
-      setLoadFailed(true);
-      return;
-    }
-    const controller = new AbortController();
-    let nextUrl: string | null = null;
-    let disposed = false;
-    void (async () => {
-      try {
-        const response = await apiFetch(
-          `${getBackendBaseURL()}/api/deep-research/sessions/${encodeURIComponent(sessionId)}/artifacts/${encodeURIComponent(name)}`,
-          { method: "GET", signal: controller.signal },
-        );
-        if (!response.ok) {
-          throw new Error(`Unable to load report image (${response.status})`);
-        }
-        const blob = await response.blob();
-        if (!blob.size) {
-          throw new Error("Report image is empty");
-        }
-        nextUrl = URL.createObjectURL(blob);
-        if (disposed) return;
-        setObjectUrl(nextUrl);
-      } catch (error) {
-        if (!disposed && !(error instanceof DOMException && error.name === "AbortError")) {
-          // Never let an optional illustration break Markdown rendering, but don't
-          // leave the user with a misleading infinite loading label either.
-          setLoadFailed(true);
-        }
-      }
-    })();
-    return () => {
-      disposed = true;
-      controller.abort();
-      if (nextUrl) URL.revokeObjectURL(nextUrl);
-    };
-  }, [retryKey, sessionId, src]);
-
-  if (!objectUrl) {
-    if (loadFailed) {
-      return (
-        <span className="my-3 flex items-center gap-2 rounded-md border border-amber-200 bg-amber-50 px-3 py-2 text-xs text-amber-800 dark:border-amber-900/70 dark:bg-amber-950/30 dark:text-amber-300">
-          报告配图加载失败
-          <button
-            type="button"
-            className="font-medium underline underline-offset-2 hover:opacity-80"
-            onClick={() => setRetryKey((value) => value + 1)}
-          >
-            重试
-          </button>
-        </span>
-      );
-    }
-    return <span className="block text-xs text-muted-foreground">正在加载报告配图…</span>;
-  }
-  return (
-    <img
-      {...props}
-      alt={alt || "研究报告配图"}
-      className={cn("my-3 max-w-full overflow-hidden rounded-lg border", props.className)}
-      src={objectUrl}
-    />
-  );
-}
+  );
+}
+
+/** Fetches a private deep-research image with the normal auth client. */
+function ProtectedResearchReportImage({
+  sessionId,
+  src,
+  alt,
+  ...props
+}: React.ImgHTMLAttributes<HTMLImageElement> & {
+  sessionId: string;
+}) {
+  const [objectUrl, setObjectUrl] = useState<string | null>(null);
+  const [loadFailed, setLoadFailed] = useState(false);
+  const [retryKey, setRetryKey] = useState(0);
+
+  useEffect(() => {
+    setObjectUrl(null);
+    setLoadFailed(false);
+    if (!src?.startsWith("deep-research://")) {
+      return;
+    }
+    const name = src.slice("deep-research://".length);
+    if (!name) {
+      setLoadFailed(true);
+      return;
+    }
+    const controller = new AbortController();
+    let nextUrl: string | null = null;
+    let disposed = false;
+    void (async () => {
+      try {
+        const response = await apiFetch(
+          `${getBackendBaseURL()}/api/deep-research/sessions/${encodeURIComponent(sessionId)}/artifacts/${encodeURIComponent(name)}`,
+          { method: "GET", signal: controller.signal },
+        );
+        if (!response.ok) {
+          throw new Error(`Unable to load report image (${response.status})`);
+        }
+        const blob = await response.blob();
+        if (!blob.size) {
+          throw new Error("Report image is empty");
+        }
+        nextUrl = URL.createObjectURL(blob);
+        if (disposed) return;
+        setObjectUrl(nextUrl);
+      } catch (error) {
+        if (!disposed && !(error instanceof DOMException && error.name === "AbortError")) {
+          // Never let an optional illustration break Markdown rendering, but don't
+          // leave the user with a misleading infinite loading label either.
+          setLoadFailed(true);
+        }
+      }
+    })();
+    return () => {
+      disposed = true;
+      controller.abort();
+      if (nextUrl) URL.revokeObjectURL(nextUrl);
+    };
+  }, [retryKey, sessionId, src]);
+
+  if (!objectUrl) {
+    if (loadFailed) {
+      return (
+        <span className="my-3 flex items-center gap-2 rounded-md border border-amber-200 bg-amber-50 px-3 py-2 text-xs text-amber-800 dark:border-amber-900/70 dark:bg-amber-950/30 dark:text-amber-300">
+          报告配图加载失败
+          <button
+            type="button"
+            className="font-medium underline underline-offset-2 hover:opacity-80"
+            onClick={() => setRetryKey((value) => value + 1)}
+          >
+            重试
+          </button>
+        </span>
+      );
+    }
+    return <span className="block text-xs text-muted-foreground">正在加载报告配图…</span>;
+  }
+  return (
+    <img
+      {...props}
+      alt={alt || "研究报告配图"}
+      className={cn("my-3 max-w-full overflow-hidden rounded-lg border", props.className)}
+      src={objectUrl}
+    />
+  );
+}
 
 export function ArtifactFilePreview({
   content,
   language,
-  threadId,
-  publicShareCode,
-  researchSessionId,
-  animated = false,
+  threadId,
+  publicShareCode,
+  researchSessionId,
+  animated = false,
   activeCursor = false,
 }: {
   content: string;
   language: string;
-  threadId: string;
-  publicShareCode?: string;
-  researchSessionId?: string;
+  threadId: string;
+  publicShareCode?: string;
+  researchSessionId?: string;
   animated?: boolean;
   activeCursor?: boolean;
 }) {
@@ -1784,7 +1785,7 @@ export function ArtifactFilePreview({
         );
       },
     };
-  }, [content, publicShareCode, researchSessionId, threadId]);
+  }, [content, publicShareCode, researchSessionId, threadId]);
 
   useEffect(() => {
     if (language !== "html") {
@@ -1849,26 +1850,26 @@ export function ArtifactFilePreview({
           animated && "animate-[sandbox-preview-enter_320ms_ease-out]",
         )}
       >
-          <Streamdown
-            className="size-full"
-            {...streamdownPlugins}
-            // react-markdown's safe default strips unknown protocols before the
-            // custom `img` renderer sees them.  Deep-research images use this
-            // private pseudo URL and are then fetched through the authenticated
-            // artifact endpoint in `SandboxPreviewImage`.
-            urlTransform={(url) =>
-              url.startsWith("deep-research://")
-                ? url
-                : defaultUrlTransform(url)
-            }
-            components={{
+          <Streamdown
+            className="size-full"
+            {...streamdownPlugins}
+            // react-markdown's safe default strips unknown protocols before the
+            // custom `img` renderer sees them.  Deep-research images use this
+            // private pseudo URL and are then fetched through the authenticated
+            // artifact endpoint in `SandboxPreviewImage`.
+            urlTransform={(url) =>
+              url.startsWith("deep-research://")
+                ? url
+                : defaultUrlTransform(url)
+            }
+            components={{
             ...markdownComponents,
             img: (props) => (
               <SandboxPreviewImage
                 {...props}
-                threadId={threadId}
-                publicShareCode={publicShareCode}
-                researchSessionId={researchSessionId}
+                threadId={threadId}
+                publicShareCode={publicShareCode}
+                researchSessionId={researchSessionId}
               />
             ),
           }}
diff --git a/frontend-web/src/components/workspace/messages/message-group.tsx b/frontend-web/src/components/workspace/messages/message-group.tsx
index 634deb28..f94c157c 100644
--- a/frontend-web/src/components/workspace/messages/message-group.tsx
+++ b/frontend-web/src/components/workspace/messages/message-group.tsx
@@ -1,21 +1,21 @@
 import type { Message } from "@langchain/langgraph-sdk";
 import {
-  BookOpenTextIcon,
-  CheckCircle2Icon,
-  ChevronDownIcon,
-  ChevronUp,
+  BookOpenTextIcon,
+  CheckCircle2Icon,
+  ChevronDownIcon,
+  ChevronUp,
   FolderOpenIcon,
   GlobeIcon,
-  LightbulbIcon,
-  ListTodoIcon,
-  Loader2Icon,
+  LightbulbIcon,
+  ListTodoIcon,
+  Loader2Icon,
   MessageCircleQuestionMarkIcon,
   NotebookPenIcon,
   SearchIcon,
   SquareTerminalIcon,
   WrenchIcon,
 } from "lucide-react";
-import { useEffect, useMemo, useState } from "react";
+import { useEffect, useMemo, useState } from "react";
 
 import {
   ChainOfThought,
@@ -31,20 +31,20 @@ import {
   CollapsibleContent,
   CollapsibleTrigger,
 } from "@/components/ui/collapsible";
-import {
-  Dialog,
+import {
+  Dialog,
   DialogContent,
   DialogDescription,
-  DialogHeader,
-  DialogTitle,
-} from "@/components/ui/dialog";
-import {
-  buildWriteFileVirtualUrl,
-  hasCompleteArtifactExtension,
-  normalizeStreamingArtifactPath,
-  provisionalWriteFilePath,
-} from "@/core/artifacts/streaming-write-preview";
-import { useI18n } from "@/core/i18n/hooks";
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
+import {
+  buildWriteFileVirtualUrl,
+  hasCompleteArtifactExtension,
+  normalizeStreamingArtifactPath,
+  provisionalWriteFilePath,
+} from "@/core/artifacts/streaming-write-preview";
+import { useI18n } from "@/core/i18n/hooks";
 import {
   normalizeSearchResults,
   resolveSearchQuery,
@@ -58,13 +58,13 @@ import { useRehypeSplitWordsIntoSpans } from "@/core/rehype";
 import { useLocalSettings } from "@/core/settings";
 import { useSkills } from "@/core/skills/hooks";
 import {
-  buildSkillDisplayMap,
-  findDisplayConfigForTool,
-  isDisplaySamplePayload,
-  normalizeDefaultDisplaySources,
-  shouldUseDefaultCitationMode,
-  type RuntimeDisplaySource,
-} from "@/core/skill-display/runtime";
+  buildSkillDisplayMap,
+  findDisplayConfigForTool,
+  isDisplaySamplePayload,
+  normalizeDefaultDisplaySources,
+  shouldUseDefaultCitationMode,
+  type RuntimeDisplaySource,
+} from "@/core/skill-display/runtime";
 import { normalizeDisplaySources } from "@/core/skill-display/display-adapter";
 import { extractTitleFromMarkdown } from "@/core/utils/markdown";
 import { env } from "@/env";
@@ -235,7 +235,7 @@ export function MessageGroup({
   );
 }
 
-function ToolCall({
+function ToolCall({
   id,
   messageId,
   name,
@@ -257,45 +257,45 @@ function ToolCall({
   ragModeEnabled?: boolean;
 }) {
   const { t } = useI18n();
-  const displayMatch =
-    result !== undefined && isDisplaySamplePayload(result)
-      ? null
-      : (findDisplayConfigForTool(name, skillDisplayMap, args) ??
-        null);
+  const displayMatch =
+    result !== undefined && isDisplaySamplePayload(result)
+      ? null
+      : (findDisplayConfigForTool(name, skillDisplayMap, args) ??
+        null);
   const displayItems =
     displayMatch && result !== undefined
-      ? normalizeDisplaySources(result, displayMatch.display).map((item, index) => ({
-          ...item,
-          index: index + 1,
-          skillName: displayMatch.skillName,
-          mode: item.displayMode ?? displayMatch.display.mode,
-        }))
+      ? normalizeDisplaySources(result, displayMatch.display).map((item, index) => ({
+          ...item,
+          index: index + 1,
+          skillName: displayMatch.skillName,
+          mode: item.displayMode ?? displayMatch.display.mode,
+        }))
       : [];
-  if (displayItems.length > 0) {
+  if (displayItems.length > 0) {
     return (
       <ChainOfThoughtStep
         key={id}
-        label={
-          displayMatch?.display.mode === "citation" || !displayMatch
-            ? "检索参考来源"
-            : `获取 ${displayItems.length} 条结果`
-        }
+        label={
+          displayMatch?.display.mode === "citation" || !displayMatch
+            ? "检索参考来源"
+            : `获取 ${displayItems.length} 条结果`
+        }
         icon={SearchIcon}
       >
         <DisplayResultsList results={displayItems} />
       </ChainOfThoughtStep>
     );
-  }
-
-  // Deep Research uses a virtual tool call for each durable writing phase.
-  // Rendering it here keeps its lifecycle in the very same ChainOfThought
-  // component as ordinary Q&A retrieval and sandbox tool calls.
-  if (name === "deep_research_progress") {
-    return <DeepResearchProgressStep id={id} args={args} />;
-  }
-
-  const searchItems = normalizeSearchResults(result);
-  if (ragModeEnabled && shouldUseDefaultCitationMode(name, result, args) && searchItems.length > 0) {
+  }
+
+  // Deep Research uses a virtual tool call for each durable writing phase.
+  // Rendering it here keeps its lifecycle in the very same ChainOfThought
+  // component as ordinary Q&A retrieval and sandbox tool calls.
+  if (name === "deep_research_progress") {
+    return <DeepResearchProgressStep id={id} args={args} />;
+  }
+
+  const searchItems = normalizeSearchResults(result);
+  if (ragModeEnabled && shouldUseDefaultCitationMode(name, result, args) && searchItems.length > 0) {
     const defaultItems = normalizeDefaultDisplaySources(result).map((item, index) => ({
       ...item,
       index: index + 1,
@@ -308,19 +308,19 @@ function ToolCall({
       </ChainOfThoughtStep>
     );
   }
-  if (name === "web_search" || searchItems.length > 0) {
-    const query = resolveSearchQuery(args, result);
-    let label: React.ReactNode = t.toolCalls.searchForRelatedInfo;
-    if (query) {
-      label =
-        name === "web_search"
-          ? `知识库检索 "${query}"`
-          : t.toolCalls.searchFor(query);
-    } else if (name === "web_search") {
-      label = "知识库检索";
-    }
-    return (
-      <ChainOfThoughtStep key={id} label={label} icon={SearchIcon}>
+  if (name === "web_search" || searchItems.length > 0) {
+    const query = resolveSearchQuery(args, result);
+    let label: React.ReactNode = t.toolCalls.searchForRelatedInfo;
+    if (query) {
+      label =
+        name === "web_search"
+          ? `知识库检索 "${query}"`
+          : t.toolCalls.searchFor(query);
+    } else if (name === "web_search") {
+      label = "知识库检索";
+    }
+    return (
+      <ChainOfThoughtStep key={id} label={label} icon={SearchIcon}>
         {searchItems.length > 0 && (
           <WebSearchResultsList results={searchItems} />
         )}
@@ -437,18 +437,18 @@ function ToolCall({
     if (!description) {
       description = t.toolCalls.writeFile;
     }
-    return (
-      <ArtifactWriteToolCall
-        id={id}
-        messageId={messageId}
-        name={name}
-        args={args}
-        result={result}
-        description={description}
-        isLast={isLast}
-        isLoading={isLoading}
-      />
-    );
+    return (
+      <ArtifactWriteToolCall
+        id={id}
+        messageId={messageId}
+        name={name}
+        args={args}
+        result={result}
+        description={description}
+        isLast={isLast}
+        isLoading={isLoading}
+      />
+    );
   } else if (name === "bash") {
     const description: string | undefined = (args as { description: string })
       ?.description;
@@ -509,161 +509,164 @@ function ToolCall({
         icon={WrenchIcon}
       ></ChainOfThoughtStep>
     );
-  }
-}
-
-function DeepResearchProgressStep({
-  id,
-  args,
-}: {
-  id?: string;
-  args: Record<string, unknown>;
-}) {
-  const label = typeof args.label === "string" && args.label.trim()
-    ? args.label
-    : "正在撰写研究报告";
-  const detail = typeof args.detail === "string" ? args.detail.trim() : "";
-  const thinking = typeof args.thinking === "string" ? args.thinking.trim() : "";
-  const active = args.status !== "complete";
-  const [thinkingOpen, setThinkingOpen] = useState(false);
-
-  useEffect(() => {
-    if (active && thinking) setThinkingOpen(true);
-  }, [active, thinking]);
-
-  return (
-    <ChainOfThoughtStep
-      key={id}
-      status={active ? "active" : "complete"}
-      icon={active
-        ? <Loader2Icon className="text-primary size-4 animate-spin" />
-        : <CheckCircle2Icon className="size-4 text-emerald-600 dark:text-emerald-400" />}
-      label={
-        <span className="flex flex-wrap items-center gap-x-2 gap-y-0.5">
-          <span>{label}</span>
-          <span className={active ? "text-primary text-xs" : "text-muted-foreground text-xs"}>
-            {active ? "进行中" : "已完成"}
-          </span>
-        </span>
-      }
-    >
-      {detail && (
-        <div className="text-muted-foreground text-xs leading-5">
-          {detail}
-        </div>
-      )}
-      {thinking && (
-        <Collapsible className="mt-2" onOpenChange={setThinkingOpen} open={thinkingOpen}>
-          <CollapsibleTrigger asChild>
-            <Button
-              aria-label={thinkingOpen ? "收起模型思考" : "展开模型思考"}
-              className="h-7 gap-1.5 px-2 text-xs"
-              size="sm"
-              type="button"
-              variant="ghost"
-            >
-              <LightbulbIcon className="size-3.5 text-amber-600 dark:text-amber-300" />
-              <span>模型思考</span>
-              <span className="text-muted-foreground">{active ? "思考中" : "已完成"}</span>
-              <ChevronDownIcon className={cn("size-3.5 transition-transform", thinkingOpen && "rotate-180")} />
-            </Button>
-          </CollapsibleTrigger>
-          <CollapsibleContent>
-            <p aria-live={active ? "polite" : undefined} className="sr-only" role={active ? "status" : undefined}>
-              {active ? "模型思考内容正在更新" : "模型思考内容已完成"}
-            </p>
-            <pre className="bg-muted/45 text-muted-foreground mt-1 max-h-56 overflow-auto rounded-lg border px-3 py-2 text-xs leading-5 whitespace-pre-wrap break-words">
-              {thinking}
-            </pre>
-          </CollapsibleContent>
-        </Collapsible>
-      )}
-    </ChainOfThoughtStep>
-  );
-}
-
-function ArtifactWriteToolCall({
-  id,
-  messageId,
-  name,
-  args,
-  result,
-  description,
-  isLast,
-  isLoading,
-}: {
-  id?: string;
-  messageId?: string;
-  name: "write_file" | "str_replace";
-  args: Record<string, unknown>;
-  result?: string | Record<string, unknown>;
-  description: string;
-  isLast: boolean;
-  isLoading: boolean;
-}) {
-  const artifacts = useArtifactsOptional();
-  const openStreamedArtifact = artifacts?.openStreamedArtifact;
-  const rawPath = typeof args.path === "string" ? args.path : "";
-  const content = typeof args.content === "string" ? args.content : "";
-  const normalizedPath = normalizeStreamingArtifactPath(rawPath);
-  const hasUsablePath =
-    Boolean(normalizedPath) && hasCompleteArtifactExtension(normalizedPath);
-  const sourcePath = hasUsablePath
-    ? normalizedPath
-    : name === "write_file" && content.trim()
-      ? provisionalWriteFilePath(content)
-      : null;
-  const previewKey = messageId && id ? `${messageId}:${id}` : null;
-  const artifactPath =
-    sourcePath && name === "write_file" && messageId && id
-      ? buildWriteFileVirtualUrl({ path: sourcePath, messageId, toolCallId: id })
-      : sourcePath;
-
-  useEffect(() => {
-    if (
-      !openStreamedArtifact ||
-      !artifactPath ||
-      !previewKey ||
-      !isLoading ||
-      !isLast ||
-      result !== undefined
-    ) {
-      return;
-    }
-    openStreamedArtifact(artifactPath, previewKey);
-  }, [
-    artifactPath,
-    isLast,
-    isLoading,
-    openStreamedArtifact,
-    previewKey,
-    result,
-  ]);
-
-  return (
-    <ChainOfThoughtStep
-      key={id}
-      className={cn(artifactPath && "cursor-pointer")}
-      label={description}
-      icon={NotebookPenIcon}
-      onClick={() => {
-        if (!artifactPath || !artifacts) return;
-        artifacts.select(artifactPath);
-        artifacts.setOpen(true);
-      }}
-    >
-      {(normalizedPath || sourcePath) && (
-        <ChainOfThoughtSearchResult className="cursor-pointer">
-          {normalizedPath || sourcePath}
-        </ChainOfThoughtSearchResult>
-      )}
-    </ChainOfThoughtStep>
-  );
-}
-
-interface GenericCoTStep<T extends string = string> {
-  id?: string;
-  messageId?: string;
+  }
+}
+
+function DeepResearchProgressStep({
+  id,
+  args,
+}: {
+  id?: string;
+  args: Record<string, unknown>;
+}) {
+  const label = typeof args.label === "string" && args.label.trim()
+    ? args.label
+    : "正在撰写研究报告";
+  const detail = typeof args.detail === "string" ? args.detail.trim() : "";
+  const thinking = typeof args.thinking === "string" ? args.thinking.trim() : "";
+  const active = args.status !== "complete";
+  const [thinkingOpen, setThinkingOpen] = useState(false);
+
+  useEffect(() => {
+    if (active && thinking) setThinkingOpen(true);
+  }, [active, thinking]);
+
+  return (
+    <ChainOfThoughtStep
+      key={id}
+      status={active ? "active" : "complete"}
+      icon={active
+        ? <Loader2Icon className="text-primary size-4 animate-spin" />
+        : <CheckCircle2Icon className="size-4 text-emerald-600 dark:text-emerald-400" />}
+      label={
+        <span className="flex flex-wrap items-center gap-x-2 gap-y-0.5">
+          <span>{label}</span>
+          <span className={active ? "text-primary text-xs" : "text-muted-foreground text-xs"}>
+            {active ? "进行中" : "已完成"}
+          </span>
+        </span>
+      }
+    >
+      {detail && (
+        <div className="text-muted-foreground text-xs leading-5">
+          {detail}
+        </div>
+      )}
+      {thinking && (
+        <Collapsible className="mt-2" onOpenChange={setThinkingOpen} open={thinkingOpen}>
+          <CollapsibleTrigger asChild>
+            <Button
+              aria-label={thinkingOpen ? "收起模型思考" : "展开模型思考"}
+              className="h-7 gap-1.5 px-2 text-xs"
+              size="sm"
+              type="button"
+              variant="ghost"
+            >
+              <LightbulbIcon className="size-3.5 text-amber-600 dark:text-amber-300" />
+              <span>模型思考</span>
+              <span className="text-muted-foreground">{active ? "思考中" : "已完成"}</span>
+              <ChevronDownIcon className={cn("size-3.5 transition-transform", thinkingOpen && "rotate-180")} />
+            </Button>
+          </CollapsibleTrigger>
+          <CollapsibleContent>
+            <p aria-live={active ? "polite" : undefined} className="sr-only" role={active ? "status" : undefined}>
+              {active ? "模型思考内容正在更新" : "模型思考内容已完成"}
+            </p>
+            <pre className="bg-muted/45 text-muted-foreground mt-1 max-h-56 overflow-auto rounded-lg border px-3 py-2 text-xs leading-5 whitespace-pre-wrap break-words">
+              {thinking}
+            </pre>
+          </CollapsibleContent>
+        </Collapsible>
+      )}
+    </ChainOfThoughtStep>
+  );
+}
+
+function ArtifactWriteToolCall({
+  id,
+  messageId,
+  name,
+  args,
+  result,
+  description,
+  isLast,
+  isLoading,
+}: {
+  id?: string;
+  messageId?: string;
+  name: "write_file" | "str_replace";
+  args: Record<string, unknown>;
+  result?: string | Record<string, unknown>;
+  description: string;
+  isLast: boolean;
+  isLoading: boolean;
+}) {
+  const artifacts = useArtifactsOptional();
+  const openStreamedArtifact = artifacts?.openStreamedArtifact;
+  const rawPath = typeof args.path === "string" ? args.path : "";
+  const content = typeof args.content === "string" ? args.content : "";
+  const normalizedPath = normalizeStreamingArtifactPath(rawPath);
+  const hasUsablePath =
+    Boolean(normalizedPath) && hasCompleteArtifactExtension(normalizedPath);
+  const sourcePath = hasUsablePath
+    ? normalizedPath
+    : name === "write_file" && content.trim()
+      ? provisionalWriteFilePath(content)
+      : null;
+  const previewKey = messageId && id ? `${messageId}:${id}` : null;
+  // Never select a bare provisional name like `未命名文件.md` — the artifacts
+  // API only serves `/mnt/user-data/...` paths and would 400. Wait until the
+  // tool call has ids so we can open a write-file: memory preview instead.
+  const artifactPath =
+    sourcePath && name === "write_file" && messageId && id
+      ? buildWriteFileVirtualUrl({ path: sourcePath, messageId, toolCallId: id })
+      : null;
+
+  useEffect(() => {
+    if (
+      !openStreamedArtifact ||
+      !artifactPath ||
+      !previewKey ||
+      !isLoading ||
+      !isLast ||
+      result !== undefined
+    ) {
+      return;
+    }
+    openStreamedArtifact(artifactPath, previewKey);
+  }, [
+    artifactPath,
+    isLast,
+    isLoading,
+    openStreamedArtifact,
+    previewKey,
+    result,
+  ]);
+
+  return (
+    <ChainOfThoughtStep
+      key={id}
+      className={cn(artifactPath && "cursor-pointer")}
+      label={description}
+      icon={NotebookPenIcon}
+      onClick={() => {
+        if (!artifactPath || !artifacts) return;
+        artifacts.select(artifactPath);
+        artifacts.setOpen(true);
+      }}
+    >
+      {(normalizedPath || sourcePath) && (
+        <ChainOfThoughtSearchResult className="cursor-pointer">
+          {normalizedPath || sourcePath}
+        </ChainOfThoughtSearchResult>
+      )}
+    </ChainOfThoughtStep>
+  );
+}
+
+interface GenericCoTStep<T extends string = string> {
+  id?: string;
+  messageId?: string;
   type: T;
 }
 
@@ -766,7 +769,7 @@ function DisplayResultsList({ results }: { results: RuntimeDisplaySource[] }) {
             open && "rotate-180",
           )}
         />
-        <span>{results.length} 条真实返回结果</span>
+        <span>{results.length} 条真实返回结果</span>
       </CollapsibleTrigger>
       <CollapsibleContent className="mt-2 flex flex-col gap-2">
         {results.map((item) => (
diff --git a/frontend-web/src/core/artifacts/hooks.ts b/frontend-web/src/core/artifacts/hooks.ts
index 0e9818ac..0f76854f 100644
--- a/frontend-web/src/core/artifacts/hooks.ts
+++ b/frontend-web/src/core/artifacts/hooks.ts
@@ -6,6 +6,7 @@ import { useThread } from "@/components/workspace/messages/context";
 import { isImageFile } from "../utils/files";
 
 import { loadArtifactContent, loadArtifactContentFromToolCall } from "./loader";
+import { isArtifactApiPath } from "./streaming-write-preview";
 import { updateArtifactContent } from "./api";
 
 function isWriteFileStreamingUrl(filepath: string): boolean {
@@ -101,7 +102,7 @@ export function useArtifactContent({
     queryFn: () => {
       return loadArtifactContent({ filepath, threadId, isMock, publicShareCode });
     },
-    enabled,
+    enabled: Boolean(enabled) && !useWriteFileStreaming && isArtifactApiPath(filepath),
     refetchInterval: thread.isLoading ? 1000 : false,
     // Cache artifact content for 5 minutes to avoid repeated fetches (especially for .skill ZIP extraction)
     staleTime: 5 * 60 * 1000,
diff --git a/frontend-web/src/core/artifacts/streaming-write-preview.test.ts b/frontend-web/src/core/artifacts/streaming-write-preview.test.ts
new file mode 100644
index 00000000..76f394c7
--- /dev/null
+++ b/frontend-web/src/core/artifacts/streaming-write-preview.test.ts
@@ -0,0 +1,32 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  isArtifactApiPath,
+  isProvisionalStreamingArtifactPath,
+  provisionalWriteFilePath,
+} from "./streaming-write-preview";
+
+test("provisionalWriteFilePath uses html only for html documents", () => {
+  assert.equal(provisionalWriteFilePath("# title"), "未命名文件.md");
+  assert.equal(provisionalWriteFilePath("<!DOCTYPE html><html>"), "未命名文件.html");
+  assert.equal(provisionalWriteFilePath("<html lang='zh'>"), "未命名文件.html");
+});
+
+test("isProvisionalStreamingArtifactPath matches the streaming placeholder names", () => {
+  assert.equal(isProvisionalStreamingArtifactPath("未命名文件.md"), true);
+  assert.equal(isProvisionalStreamingArtifactPath("/未命名文件.html"), true);
+  assert.equal(isProvisionalStreamingArtifactPath("mnt/user-data/outputs/report.md"), false);
+});
+
+test("isArtifactApiPath rejects write-file URLs and placeholder names", () => {
+  assert.equal(isArtifactApiPath("未命名文件.md"), false);
+  assert.equal(
+    isArtifactApiPath(
+      "write-file:未命名文件.md?message_id=m1&tool_call_id=t1&language=markdown",
+    ),
+    false,
+  );
+  assert.equal(isArtifactApiPath("mnt/user-data/outputs/report.md"), true);
+  assert.equal(isArtifactApiPath("/mnt/user-data/outputs/report.md"), true);
+});
diff --git a/frontend-web/src/core/artifacts/streaming-write-preview.ts b/frontend-web/src/core/artifacts/streaming-write-preview.ts
index bccccd5b..c2ec791f 100644
--- a/frontend-web/src/core/artifacts/streaming-write-preview.ts
+++ b/frontend-web/src/core/artifacts/streaming-write-preview.ts
@@ -23,6 +23,11 @@ export function hasCompleteArtifactExtension(path: string): boolean {
   return /\.[a-z0-9]{2,12}$/i.test(filename);
 }
 
+export const PROVISIONAL_WRITE_FILE_NAMES = new Set([
+  "未命名文件.md",
+  "未命名文件.html",
+]);
+
 export function provisionalWriteFilePath(content: string): string {
   const head = content.slice(0, 256).trimStart().toLowerCase();
   if (head.startsWith("<!doctype html") || head.startsWith("<html")) {
@@ -31,6 +36,29 @@ export function provisionalWriteFilePath(content: string): string {
   return "未命名文件.md";
 }
 
+export function isProvisionalStreamingArtifactPath(path: string): boolean {
+  const pathname =
+    normalizeStreamingArtifactPath(path).split(/[?#]/, 1)[0] ?? "";
+  const filename = pathname.split("/").filter(Boolean).at(-1) ?? "";
+  return PROVISIONAL_WRITE_FILE_NAMES.has(filename);
+}
+
+/** Paths the artifacts HTTP API can actually serve (sandbox virtual paths). */
+export function isArtifactApiPath(path: string): boolean {
+  if (!path || path.startsWith("write-file:")) {
+    return false;
+  }
+  if (isProvisionalStreamingArtifactPath(path)) {
+    return false;
+  }
+  const normalized = path.replace(/^\/+/, "").replace(/\\/g, "/");
+  return (
+    normalized === "mnt/user-data" ||
+    normalized.startsWith("mnt/user-data/") ||
+    normalized.startsWith("mnt/skills/")
+  );
+}
+
 export function languageOfStreamingArtifact(
   path: string,
 ): StreamingArtifactLanguage | null {
diff --git a/frontend-web/src/core/threads/hooks.ts b/frontend-web/src/core/threads/hooks.ts
index 5c235bb1..5f64fa67 100644
--- a/frontend-web/src/core/threads/hooks.ts
+++ b/frontend-web/src/core/threads/hooks.ts
@@ -24,79 +24,83 @@ import type { UploadedFileInfo } from "../uploads";
 import { promptInputFilePartToFile, uploadFiles } from "../uploads";
 
 import type { AgentThread, AgentThreadState } from "./types";
+import {
+  isAbortLikeError,
+  isTransientStreamTransportError,
+} from "./thread-access-error";
 
-export type ToolEndEvent = {
-  name: string;
-  data: unknown;
-  toolCallId?: string;
-};
-
-export type ToolStartEvent = ToolEndEvent;
+export type ToolEndEvent = {
+  name: string;
+  data: unknown;
+  toolCallId?: string;
+};
 
-export type ThreadStreamOptions = {
-  threadId?: string | null | undefined;
-  context: LocalSettings["context"];
-  isMock?: boolean;
-  assistantId?: string;
-  /**
-   * Per-page run behaviour.  Most chats keep the SDK defaults; long-running
-   * workspace flows can opt into a resumable stream without changing global
-   * chat semantics.
-   */
-  runOptions?: {
-    onDisconnect?: "cancel" | "continue";
-    multitaskStrategy?: "reject" | "rollback" | "interrupt" | "enqueue";
-  };
+export type ToolStartEvent = ToolEndEvent;
+
+export type ThreadStreamOptions = {
+  threadId?: string | null | undefined;
+  context: LocalSettings["context"];
+  isMock?: boolean;
+  assistantId?: string;
+  /**
+   * Per-page run behaviour.  Most chats keep the SDK defaults; long-running
+   * workspace flows can opt into a resumable stream without changing global
+   * chat semantics.
+   */
+  runOptions?: {
+    onDisconnect?: "cancel" | "continue";
+    multitaskStrategy?: "reject" | "rollback" | "interrupt" | "enqueue";
+  };
   /** 额外写到新建 thread 的 metadata（与 agent_id 合并）。
    *  任务深链用 `{ taskId }` 把对话挂到任务下（1:N），列表按 metadata.taskId 过滤。 */
   threadMetadata?: Record<string, unknown>;
-  onStart?: (threadId: string) => void;
-  onFinish?: (state: AgentThreadState) => void;
-  onToolStart?: (event: ToolStartEvent) => void;
-  onToolEnd?: (event: ToolEndEvent) => void;
-};
+  onStart?: (threadId: string) => void;
+  onFinish?: (state: AgentThreadState) => void;
+  onToolStart?: (event: ToolStartEvent) => void;
+  onToolEnd?: (event: ToolEndEvent) => void;
+};
 
-type SendMessageOptions = {
-  additionalKwargs?: Record<string, unknown>;
-  /**
-   * Extra human-context messages submitted before the visible user message.
-   * They are persisted with `hide_from_ui` so the model receives rich business
-   * context without dumping long prompts into the conversation surface.
-   */
-  hiddenContext?:
-    | string
-    | {
-        text: string;
-        name?: string;
-        additionalKwargs?: Record<string, unknown>;
-      }
-    | Array<{
-        text: string;
-        name?: string;
-        additionalKwargs?: Record<string, unknown>;
-      }>;
-};
-
-type ThreadTitleRefreshState = Pick<AgentThreadState, "title"> & {
-  title_provisional?: boolean;
-};
-
-function normalizeHiddenContextMessages(options?: SendMessageOptions) {
-  const value = options?.hiddenContext;
-  if (!value) return [];
-  const items =
-    typeof value === "string"
-      ? [{ text: value }]
-      : Array.isArray(value)
-        ? value
-        : [value];
-  return items
-    .map((item) => ({
-      ...item,
-      text: item.text.trim(),
-    }))
-    .filter((item) => item.text.length > 0);
-}
+type SendMessageOptions = {
+  additionalKwargs?: Record<string, unknown>;
+  /**
+   * Extra human-context messages submitted before the visible user message.
+   * They are persisted with `hide_from_ui` so the model receives rich business
+   * context without dumping long prompts into the conversation surface.
+   */
+  hiddenContext?:
+    | string
+    | {
+        text: string;
+        name?: string;
+        additionalKwargs?: Record<string, unknown>;
+      }
+    | Array<{
+        text: string;
+        name?: string;
+        additionalKwargs?: Record<string, unknown>;
+      }>;
+};
+
+type ThreadTitleRefreshState = Pick<AgentThreadState, "title"> & {
+  title_provisional?: boolean;
+};
+
+function normalizeHiddenContextMessages(options?: SendMessageOptions) {
+  const value = options?.hiddenContext;
+  if (!value) return [];
+  const items =
+    typeof value === "string"
+      ? [{ text: value }]
+      : Array.isArray(value)
+        ? value
+        : [value];
+  return items
+    .map((item) => ({
+      ...item,
+      text: item.text.trim(),
+    }))
+    .filter((item) => item.text.length > 0);
+}
 
 function normalizeStoredRunId(runId: string | null): string | null {
   if (!runId) {
@@ -206,7 +210,7 @@ export async function stopThreadRun(
   }
 }
 
-function getStreamErrorMessage(error: unknown): string {
+function getStreamErrorMessage(error: unknown): string {
   if (typeof error === "string" && error.trim()) {
     return error;
   }
@@ -226,52 +230,52 @@ function getStreamErrorMessage(error: unknown): string {
       return nestedError;
     }
   }
-  return "Request failed.";
-}
-
-const TERMINAL_RUN_STATUSES = new Set([
-  "success",
-  "error",
-  "timeout",
-  "interrupted",
-]);
-
-// A completed server run normally sends a terminal SSE event.  In local
-// development, however, a Vite hot update, a proxy disconnect, or a brief
-// network interruption can make the browser miss that final event while the
-// backend continues (and successfully completes) the run.  Do not probe on
-// every render: only treat the stream as suspicious after it has been quiet
-// for a while, then reconcile it from the authoritative run/state endpoints.
-const STREAM_RECONCILIATION_IDLE_MS = 12_000;
-const STREAM_RECONCILIATION_POLL_MS = 5_000;
-// A run can legitimately be quiet while a long tool call is in progress, so
-// reconnect more conservatively than the terminal-status check above.  The
-// reconnection only replaces the local SSE reader; the backend run keeps going.
-const STREAM_RECONNECT_IDLE_MS = 30_000;
-const STREAM_RECONNECT_MAX_ATTEMPTS = 3;
-
-async function fetchThreadTitleRefreshState(
-  threadId: string,
-  signal?: AbortSignal,
-): Promise<ThreadTitleRefreshState | null> {
-  const response = await apiFetch(
-    `${getBackendBaseURL()}/api/threads/${encodeURIComponent(threadId)}/state`,
-    { signal },
-  );
-  if (!response.ok) {
-    return null;
-  }
-  const json = (await response.json()) as {
-    values?: { title?: string; title_provisional?: boolean };
-  };
-  if (!json.values) {
-    return null;
-  }
-  return {
-    title: json.values.title ?? "",
-    title_provisional: json.values.title_provisional,
-  };
-}
+  return "Request failed.";
+}
+
+const TERMINAL_RUN_STATUSES = new Set([
+  "success",
+  "error",
+  "timeout",
+  "interrupted",
+]);
+
+// A completed server run normally sends a terminal SSE event.  In local
+// development, however, a Vite hot update, a proxy disconnect, or a brief
+// network interruption can make the browser miss that final event while the
+// backend continues (and successfully completes) the run.  Do not probe on
+// every render: only treat the stream as suspicious after it has been quiet
+// for a while, then reconcile it from the authoritative run/state endpoints.
+const STREAM_RECONCILIATION_IDLE_MS = 12_000;
+const STREAM_RECONCILIATION_POLL_MS = 5_000;
+// A run can legitimately be quiet while a long tool call / slow model write is
+// in progress. Reconnect only after a long stall; replacing the local reader
+// must NOT cancel the backend run (see reconnect below).
+const STREAM_RECONNECT_IDLE_MS = 90_000;
+const STREAM_RECONNECT_MAX_ATTEMPTS = 3;
+
+async function fetchThreadTitleRefreshState(
+  threadId: string,
+  signal?: AbortSignal,
+): Promise<ThreadTitleRefreshState | null> {
+  const response = await apiFetch(
+    `${getBackendBaseURL()}/api/threads/${encodeURIComponent(threadId)}/state`,
+    { signal },
+  );
+  if (!response.ok) {
+    return null;
+  }
+  const json = (await response.json()) as {
+    values?: { title?: string; title_provisional?: boolean };
+  };
+  if (!json.values) {
+    return null;
+  }
+  return {
+    title: json.values.title ?? "",
+    title_provisional: json.values.title_provisional,
+  };
+}
 
 /**
  * Detect "thread not found" / forbidden errors from the LangGraph SDK.
@@ -319,37 +323,37 @@ function isRunNotFoundError(message: string): boolean {
  * 「already has an active run」。匹配 HTTP 409、英文兜底文案，或后端已中文化
  * 的提示，统一映射成一句友好的中文。
  */
-function isActiveRunConflictError(message: string): boolean {
-  return (
-    /\b409\b/.test(message) ||
-    /already has an active run/i.test(message) ||
-    /还在生成回答/.test(message)
-  );
-}
-
-function isModelConcurrencyLimitError(message: string): boolean {
-  return (
-    /\b429\b/.test(message) ||
-    /并发已达到上限/.test(message) ||
-    /并发调用已达到上限/.test(message) ||
-    /使用人数较多/.test(message) ||
-    /too many requests/i.test(message)
-  );
-}
-
-function friendlySendLimitMessage(message: string): string | null {
-  if (isActiveRunConflictError(message)) {
-    return "当前对话还在生成回答，请等待本轮回复结束，或先点“停止”再发送新的问题。";
-  }
-  if (isModelConcurrencyLimitError(message)) {
-    return /当前账号对该模型/.test(message)
-      ? "当前账号对该模型的并发调用已达到上限，请等待已有回答结束后再试。"
-      : "当前使用人数较多，请稍等一下再试。";
-  }
-  return null;
-}
-
-function buildCurrentUserLabel(): string {
+function isActiveRunConflictError(message: string): boolean {
+  return (
+    /\b409\b/.test(message) ||
+    /already has an active run/i.test(message) ||
+    /还在生成回答/.test(message)
+  );
+}
+
+function isModelConcurrencyLimitError(message: string): boolean {
+  return (
+    /\b429\b/.test(message) ||
+    /并发已达到上限/.test(message) ||
+    /并发调用已达到上限/.test(message) ||
+    /使用人数较多/.test(message) ||
+    /too many requests/i.test(message)
+  );
+}
+
+function friendlySendLimitMessage(message: string): string | null {
+  if (isActiveRunConflictError(message)) {
+    return "当前对话还在生成回答，请等待本轮回复结束，或先点“停止”再发送新的问题。";
+  }
+  if (isModelConcurrencyLimitError(message)) {
+    return /当前账号对该模型/.test(message)
+      ? "当前账号对该模型的并发调用已达到上限，请等待已有回答结束后再试。"
+      : "当前使用人数较多，请稍等一下再试。";
+  }
+  return null;
+}
+
+function buildCurrentUserLabel(): string {
   const auth = getStoredAuth();
   if (!auth) {
     return "未登录";
@@ -424,24 +428,24 @@ function lastHumanFromChatModelInput(input: unknown): string {
       if (Array.isArray(m)) m.forEach(push);
       else if (m != null) flat.push(m);
     };
-    push(raw);
-    for (let i = flat.length - 1; i >= 0; i--) {
-      const m = flat[i];
-      if (!m || typeof m !== "object") continue;
-      const obj = m as Record<string, unknown>;
-      const type = obj.type ?? obj.role;
-      if (type === "human" || type === "user") {
-        const kwargs = obj.additional_kwargs;
-        if (
-          kwargs &&
-          typeof kwargs === "object" &&
-          (kwargs as Record<string, unknown>).hide_from_ui === true
-        ) {
-          continue;
-        }
-        const text = textFromChatModelOutput(m);
-        if (text) return text;
-      }
+    push(raw);
+    for (let i = flat.length - 1; i >= 0; i--) {
+      const m = flat[i];
+      if (!m || typeof m !== "object") continue;
+      const obj = m as Record<string, unknown>;
+      const type = obj.type ?? obj.role;
+      if (type === "human" || type === "user") {
+        const kwargs = obj.additional_kwargs;
+        if (
+          kwargs &&
+          typeof kwargs === "object" &&
+          (kwargs as Record<string, unknown>).hide_from_ui === true
+        ) {
+          continue;
+        }
+        const text = textFromChatModelOutput(m);
+        if (text) return text;
+      }
     }
   } catch {
     /* 取不到忽略 */
@@ -452,45 +456,45 @@ function lastHumanFromChatModelInput(input: unknown): string {
 export function useThreadStream({
   threadId,
   context,
-  isMock,
-  assistantId,
-  runOptions,
-  threadMetadata,
-  onStart,
-  onFinish,
-  onToolStart,
-  onToolEnd,
-}: ThreadStreamOptions) {
+  isMock,
+  assistantId,
+  runOptions,
+  threadMetadata,
+  onStart,
+  onFinish,
+  onToolStart,
+  onToolEnd,
+}: ThreadStreamOptions) {
   const { t } = useI18n();
   const [localSettings] = useLocalSettings();
   // Track the thread ID that is currently streaming to handle thread changes during streaming
   const [onStreamThreadId, setOnStreamThreadId] = useState(() => threadId);
   // Ref to track current thread ID across async callbacks without causing re-renders,
   // and to allow access to the current thread id in onUpdateEvent
-  const threadIdRef = useRef<string | null>(threadId ?? null);
-  const startedRef = useRef(false);
-  const lastStreamActivityAtRef = useRef(0);
-  const streamReconciliationInFlightRef = useRef(false);
-  const streamReconnectAttemptsRef = useRef(0);
-  const streamReconnectFailureToastShownRef = useRef(false);
-
-  const markStreamActivity = useCallback(() => {
-    lastStreamActivityAtRef.current = Date.now();
-    streamReconnectAttemptsRef.current = 0;
-    streamReconnectFailureToastShownRef.current = false;
-  }, []);
+  const threadIdRef = useRef<string | null>(threadId ?? null);
+  const startedRef = useRef(false);
+  const lastStreamActivityAtRef = useRef(0);
+  const streamReconciliationInFlightRef = useRef(false);
+  const streamReconnectAttemptsRef = useRef(0);
+  const streamReconnectFailureToastShownRef = useRef(false);
 
-  const listeners = useRef({
-    onStart,
-    onFinish,
-    onToolStart,
-    onToolEnd,
-  });
+  const markStreamActivity = useCallback(() => {
+    lastStreamActivityAtRef.current = Date.now();
+    streamReconnectAttemptsRef.current = 0;
+    streamReconnectFailureToastShownRef.current = false;
+  }, []);
+
+  const listeners = useRef({
+    onStart,
+    onFinish,
+    onToolStart,
+    onToolEnd,
+  });
 
   // Keep listeners ref updated with latest callbacks
-  useEffect(() => {
-    listeners.current = { onStart, onFinish, onToolStart, onToolEnd };
-  }, [onStart, onFinish, onToolStart, onToolEnd]);
+  useEffect(() => {
+    listeners.current = { onStart, onFinish, onToolStart, onToolEnd };
+  }, [onStart, onFinish, onToolStart, onToolEnd]);
 
   useEffect(() => {
     const normalizedThreadId = threadId ?? null;
@@ -511,14 +515,14 @@ export function useThreadStream({
     }
   }, []);
 
-  const handleStreamStart = useCallback(
-    (_threadId: string) => {
-      threadIdRef.current = _threadId;
-      markStreamActivity();
-      _handleOnStart(_threadId);
-    },
-    [_handleOnStart, markStreamActivity],
-  );
+  const handleStreamStart = useCallback(
+    (_threadId: string) => {
+      threadIdRef.current = _threadId;
+      markStreamActivity();
+      _handleOnStart(_threadId);
+    },
+    [_handleOnStart, markStreamActivity],
+  );
 
   const queryClient = useQueryClient();
   const updateSubtask = useUpdateSubtask();
@@ -526,6 +530,9 @@ export function useThreadStream({
   const runMetadataStorageRef = useRef<
     ReturnType<typeof getRunMetadataStorage> | undefined
   >(undefined);
+  const joinStreamRef = useRef<(runId: string) => Promise<unknown>>(
+    async () => undefined,
+  );
 
   if (
     typeof window !== "undefined" &&
@@ -542,8 +549,8 @@ export function useThreadStream({
       ? () => runMetadataStorageRef.current!
       : false,
     fetchStateHistory: { limit: 1 },
-    onCreated(meta) {
-      handleStreamStart(meta.thread_id);
+    onCreated(meta) {
+      handleStreamStart(meta.thread_id);
       setOnStreamThreadId(meta.thread_id);
       const metadataAgentId = context.agent_id ?? context.agent_name;
       const extraMetadata =
@@ -557,9 +564,9 @@ export function useThreadStream({
           .threads.update(meta.thread_id, { metadata })
           .catch(() => ({}));
       }
-    },
-    onLangChainEvent(event) {
-      markStreamActivity();
+    },
+    onLangChainEvent(event) {
+      markStreamActivity();
       // 操作日志(Y-Log)：每一次大模型调用结束都各上报一条（一次 LLM 调用 = 一条），
       // 让问答日志尽量「多、全」——一个问答轮次里 lead agent / 子代理的每次模型调用
       // 都会落一条。门控与失败静默都在 writeYLog 内部处理，绝不影响问答。
@@ -581,35 +588,35 @@ export function useThreadStream({
         } catch {
           /* 上报绝不影响问答 */
         }
-      }
-    },
-    // The SDK emits UI tool lifecycle events on the dedicated `tools` stream
-    // mode. `events` is a separate LangChain trace channel; using it for UI
-    // reactions can miss a tool that the conversation has already rendered.
-    onToolEvent:
-      onToolStart || onToolEnd
-        ? (event) => {
-            markStreamActivity();
-            if (event.event === "on_tool_start") {
-              listeners.current.onToolStart?.({
-                name: event.name,
-                data: event.input,
-                toolCallId: event.toolCallId,
-              });
-              return;
-            }
-            if (event.event === "on_tool_end") {
-              listeners.current.onToolEnd?.({
-                name: event.name,
-                data: event.output,
-                toolCallId: event.toolCallId,
-              });
-            }
-          }
-        : undefined,
-    onUpdateEvent(data) {
-      markStreamActivity();
-      const updates: Array<Partial<AgentThreadState> | null> = Object.values(
+      }
+    },
+    // The SDK emits UI tool lifecycle events on the dedicated `tools` stream
+    // mode. `events` is a separate LangChain trace channel; using it for UI
+    // reactions can miss a tool that the conversation has already rendered.
+    onToolEvent:
+      onToolStart || onToolEnd
+        ? (event) => {
+            markStreamActivity();
+            if (event.event === "on_tool_start") {
+              listeners.current.onToolStart?.({
+                name: event.name,
+                data: event.input,
+                toolCallId: event.toolCallId,
+              });
+              return;
+            }
+            if (event.event === "on_tool_end") {
+              listeners.current.onToolEnd?.({
+                name: event.name,
+                data: event.output,
+                toolCallId: event.toolCallId,
+              });
+            }
+          }
+        : undefined,
+    onUpdateEvent(data) {
+      markStreamActivity();
+      const updates: Array<Partial<AgentThreadState> | null> = Object.values(
         data || {},
       );
       for (const update of updates) {
@@ -630,10 +637,10 @@ export function useThreadStream({
           );
         }
       }
-    },
-    onCustomEvent(event: unknown) {
-      markStreamActivity();
-      if (
+    },
+    onCustomEvent(event: unknown) {
+      markStreamActivity();
+      if (
         typeof event === "object" &&
         event !== null &&
         "type" in event &&
@@ -648,20 +655,20 @@ export function useThreadStream({
         return;
       }
 
-      if (
-        typeof event === "object" &&
-        event !== null &&
-        "type" in event &&
-        event.type === "llm_retry" &&
+      if (
+        typeof event === "object" &&
+        event !== null &&
+        "type" in event &&
+        event.type === "llm_retry" &&
         "message" in event &&
-        typeof event.message === "string" &&
-        event.message.trim()
-      ) {
-        // The backend is already handling this with bounded retry/backoff.
-        // Surfacing every transient model retry as a toast made normal model
-        // stalls look like repeated "network fluctuation" failures.
-        return;
-      }
+        typeof event.message === "string" &&
+        event.message.trim()
+      ) {
+        // The backend is already handling this with bounded retry/backoff.
+        // Surfacing every transient model retry as a toast made normal model
+        // stalls look like repeated "network fluctuation" failures.
+        return;
+      }
 
       // Context compression about to run a (blocking) summarization LLM call —
       // surface a transient hint so the wait before the answer streams isn't a
@@ -678,11 +685,35 @@ export function useThreadStream({
         const e = event as { type: "context_compacting"; message: string };
         toast(e.message);
       }
-    },
-    onError(error) {
-      markStreamActivity();
-      setOptimisticMessages([]);
+    },
+    onError(error) {
+      markStreamActivity();
       const message = getStreamErrorMessage(error);
+      // Replacing a stalled local SSE reader aborts the in-flight fetch. That
+      // is expected and must not look like a user-facing "network" failure.
+      if (isAbortLikeError(error)) {
+        return;
+      }
+      // A dropped SSE while the backend run is still alive: rejoin instead of
+      // toasting "Failed to fetch" / 网络波动 and leaving the answer half-done.
+      if (isTransientStreamTransportError(message)) {
+        const staleThreadId = threadIdRef.current ?? onStreamThreadId ?? null;
+        const runId = staleThreadId
+          ? runMetadataStorageRef.current?.getItem(`lg:stream:${staleThreadId}`)
+          : null;
+        if (
+          runId &&
+          streamReconnectAttemptsRef.current < STREAM_RECONNECT_MAX_ATTEMPTS
+        ) {
+          streamReconnectAttemptsRef.current += 1;
+          lastStreamActivityAtRef.current = Date.now();
+          void joinStreamRef.current(runId).catch(() => {
+            // Reconciliation will retry while the run stays non-terminal.
+          });
+          return;
+        }
+      }
+      setOptimisticMessages([]);
       // A stale auto-reconnect ("Run <id> not found") after a backend restart:
       // drop the dirty ``lg:stream:{threadId}`` key so switching back into this
       // conversation stops re-firing the same 404, and render from history
@@ -731,29 +762,29 @@ export function useThreadStream({
         }
         return;
       }
-      // 上一轮还没结束又发了新问题（409）或并发达到上限（429）：
-      // 给一句明确的中文提示，而不是把原始 HTTP 错误抛给用户。
-      const friendly = friendlySendLimitMessage(message);
-      if (friendly) {
-        toast.info(friendly);
-        return;
-      }
-      toast.error(message);
-    },
-    onFinish(state) {
-      markStreamActivity();
-      listeners.current.onFinish?.(state.values);
-      void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
-    },
+      // 上一轮还没结束又发了新问题（409）或并发达到上限（429）：
+      // 给一句明确的中文提示，而不是把原始 HTTP 错误抛给用户。
+      const friendly = friendlySendLimitMessage(message);
+      if (friendly) {
+        toast.info(friendly);
+        return;
+      }
+      toast.error(message);
+    },
+    onFinish(state) {
+      markStreamActivity();
+      listeners.current.onFinish?.(state.values);
+      void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
+    },
   });
 
   // Optimistic messages shown before the server stream responds
-  const [optimisticMessages, setOptimisticMessages] = useState<Message[]>([]);
-  const [isUploading, setIsUploading] = useState(false);
-  const [threadValueOverrides, setThreadValueOverrides] = useState<
-    Partial<AgentThreadState>
-  >({});
-  const sendInFlightRef = useRef(false);
+  const [optimisticMessages, setOptimisticMessages] = useState<Message[]>([]);
+  const [isUploading, setIsUploading] = useState(false);
+  const [threadValueOverrides, setThreadValueOverrides] = useState<
+    Partial<AgentThreadState>
+  >({});
+  const sendInFlightRef = useRef(false);
   // Carries the ask time of an in-flight send until the server-assigned human
   // message id shows up, so we can bind the timestamp to the real id (see the
   // reconciliation effect below). ``known`` is the set of human ids that
@@ -767,136 +798,147 @@ export function useThreadStream({
   // Keep a ref to the latest `thread` so the threadId-change effect can stop
   // an in-flight stream without re-running on every render that produces a
   // new `thread` identity.
-  const threadStreamRef = useRef(thread);
-  threadStreamRef.current = thread;
-
-  useEffect(() => {
-    const activeThreadId = threadIdRef.current ?? onStreamThreadId ?? null;
-    if (!activeThreadId || typeof window === "undefined") {
-      return;
-    }
-
-    let disposed = false;
-    let refreshTimer: number | null = null;
-
-    const reconcileRun = async () => {
-      if (
-        disposed ||
-        streamReconciliationInFlightRef.current ||
-        Date.now() - lastStreamActivityAtRef.current < STREAM_RECONCILIATION_IDLE_MS
-      ) {
-        return;
-      }
-
-      const storage = runMetadataStorageRef.current;
-      const runId = storage?.getItem(`lg:stream:${activeThreadId}`);
-      if (!runId) return;
-
-      streamReconciliationInFlightRef.current = true;
-      try {
-        const client = getAPIClient(isMock);
-        const run = await client.runs.get(activeThreadId, runId);
-        if (disposed) {
-          return;
-        }
-
-        if (!TERMINAL_RUN_STATUSES.has(run.status)) {
-          // ``useStream`` retries one failed connection on its own.  If that
-          // reader quietly stalls, however, its internal queue never gets a
-          // terminal error and the page remains frozen despite the backend
-          // continuing the run.  Abort only the local reader, then join the
-          // same run so no work or tokens are lost server-side.
-          if (Date.now() - lastStreamActivityAtRef.current < STREAM_RECONNECT_IDLE_MS) {
-            return;
-          }
-
-          if (streamReconnectAttemptsRef.current >= STREAM_RECONNECT_MAX_ATTEMPTS) {
-            if (!streamReconnectFailureToastShownRef.current) {
-              streamReconnectFailureToastShownRef.current = true;
-              toast.error("回答仍在后台处理中，但页面连接暂未恢复；请稍后返回此会话查看结果。");
-            }
-            return;
-          }
-
-          streamReconnectAttemptsRef.current += 1;
-          // Avoid enqueueing another reconnect before this new reader has had
-          // enough time to receive its first event.  A genuine event resets
-          // the attempt counter through ``markStreamActivity``.
-          lastStreamActivityAtRef.current = Date.now();
-
-          const stream = threadStreamRef.current;
-          void Promise.resolve(stream.stop())
-            .catch(() => {
-              // Stopping a stale local reader is best-effort; joining is still
-              // useful if the SDK already considers the stream stopped.
-            })
-            .finally(() => {
-              if (disposed || threadIdRef.current !== activeThreadId) return;
-              void stream.joinStream(runId).catch(() => {
-                // The status poll will either reconcile a terminal run or
-                // schedule the next bounded reconnect attempt.
-              });
-            });
-          return;
-        }
-
-        // The server is already terminal, so the existing SSE listener cannot
-        // receive any more useful events.  Load the checkpoint directly before
-        // resetting the SDK stream; this preserves the normal onFinish side
-        // effects (e.g. marking a position delivery complete) even when the
-        // browser missed the terminal event or already reported a transport
-        // error and dropped ``isLoading``.
-        const finalState = await client.threads.getState(activeThreadId);
-        if (disposed) {
-          return;
-        }
-
-        storage?.removeItem(`lg:stream:${activeThreadId}`);
-        streamReconnectAttemptsRef.current = 0;
-        streamReconnectFailureToastShownRef.current = false;
-        if (run.status === "success") {
-          setOptimisticMessages([]);
-          setThreadValueOverrides(finalState.values as Partial<AgentThreadState>);
-          listeners.current.onFinish?.(finalState.values as AgentThreadState);
-          void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
-        } else {
-          setThreadValueOverrides(finalState.values as Partial<AgentThreadState>);
-          toast.error("本轮生成未能完成，已同步当前对话内容，可重新发起请求。");
-        }
-
-        // Changing the controlled thread id clears only the local SDK stream
-        // (it does not cancel the already-terminal backend run). Switching it
-        // back immediately makes useStream fetch the persisted messages, so
-        // the page exits the false loading state without a manual refresh.
-        setOnStreamThreadId(null);
-        refreshTimer = window.setTimeout(() => {
-          if (!disposed && threadIdRef.current === activeThreadId) {
-            setOnStreamThreadId(activeThreadId);
-          }
-        }, 0);
-      } catch {
-        // A transient status lookup failure must not disrupt a real stream;
-        // the next polling interval will try again if it is still quiet.
-      } finally {
-        if (!disposed) {
-          streamReconciliationInFlightRef.current = false;
-        }
-      }
-    };
-
-    const interval = window.setInterval(
-      () => void reconcileRun(),
-      STREAM_RECONCILIATION_POLL_MS,
-    );
-
-    return () => {
-      disposed = true;
-      window.clearInterval(interval);
-      if (refreshTimer !== null) {
-        window.clearTimeout(refreshTimer);
-      }
-    };
-  }, [isMock, onStreamThreadId, queryClient, thread.isLoading]);
+  const threadStreamRef = useRef(thread);
+  threadStreamRef.current = thread;
+  joinStreamRef.current = (runId: string) => thread.joinStream(runId);
+
+  useEffect(() => {
+    const activeThreadId = threadIdRef.current ?? onStreamThreadId ?? null;
+    if (!activeThreadId || typeof window === "undefined") {
+      return;
+    }
+
+    let disposed = false;
+    let refreshTimer: number | null = null;
+
+    const reconcileRun = async () => {
+      if (
+        disposed ||
+        streamReconciliationInFlightRef.current ||
+        Date.now() - lastStreamActivityAtRef.current < STREAM_RECONCILIATION_IDLE_MS
+      ) {
+        return;
+      }
+
+      const storage = runMetadataStorageRef.current;
+      const runId = storage?.getItem(`lg:stream:${activeThreadId}`);
+      if (!runId) return;
+
+      streamReconciliationInFlightRef.current = true;
+      try {
+        const client = getAPIClient(isMock);
+        const run = await client.runs.get(activeThreadId, runId);
+        if (disposed) {
+          return;
+        }
+
+        if (!TERMINAL_RUN_STATUSES.has(run.status)) {
+          // ``useStream`` retries one failed connection on its own.  If that
+          // reader quietly stalls, however, its internal queue never gets a
+          // terminal error and the page remains frozen despite the backend
+          // continuing the run.
+          //
+          // SDK ``stop()`` is *not* a local-only abort: its onStop hook calls
+          // ``runs.cancel`` and deletes ``lg:stream:{threadId}``, which is
+          // exactly "答一半就不答了". Hide the run id first so stop() only
+          // aborts the browser reader, then join the still-running server run.
+          if (Date.now() - lastStreamActivityAtRef.current < STREAM_RECONNECT_IDLE_MS) {
+            return;
+          }
+
+          if (streamReconnectAttemptsRef.current >= STREAM_RECONNECT_MAX_ATTEMPTS) {
+            if (!streamReconnectFailureToastShownRef.current) {
+              streamReconnectFailureToastShownRef.current = true;
+              toast.error("回答仍在后台处理中，但页面连接暂未恢复；请稍后返回此会话查看结果。");
+            }
+            return;
+          }
+
+          streamReconnectAttemptsRef.current += 1;
+          // Avoid enqueueing another reconnect before this new reader has had
+          // enough time to receive its first event.  A genuine event resets
+          // the attempt counter through ``markStreamActivity``.
+          lastStreamActivityAtRef.current = Date.now();
+
+          const stream = threadStreamRef.current;
+          storage?.removeItem(`lg:stream:${activeThreadId}`);
+          void Promise.resolve(stream.stop())
+            .catch(() => {
+              // Stopping a stale local reader is best-effort; joining is still
+              // useful if the SDK already considers the stream stopped.
+            })
+            .finally(() => {
+              if (disposed || threadIdRef.current !== activeThreadId) return;
+              try {
+                storage?.setItem(`lg:stream:${activeThreadId}`, runId);
+              } catch {
+                /* noop */
+              }
+              void stream.joinStream(runId).catch(() => {
+                // The status poll will either reconcile a terminal run or
+                // schedule the next bounded reconnect attempt.
+              });
+            });
+          return;
+        }
+
+        // The server is already terminal, so the existing SSE listener cannot
+        // receive any more useful events.  Load the checkpoint directly before
+        // resetting the SDK stream; this preserves the normal onFinish side
+        // effects (e.g. marking a position delivery complete) even when the
+        // browser missed the terminal event or already reported a transport
+        // error and dropped ``isLoading``.
+        const finalState = await client.threads.getState(activeThreadId);
+        if (disposed) {
+          return;
+        }
+
+        storage?.removeItem(`lg:stream:${activeThreadId}`);
+        streamReconnectAttemptsRef.current = 0;
+        streamReconnectFailureToastShownRef.current = false;
+        if (run.status === "success") {
+          setOptimisticMessages([]);
+          setThreadValueOverrides(finalState.values as Partial<AgentThreadState>);
+          listeners.current.onFinish?.(finalState.values as AgentThreadState);
+          void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
+        } else {
+          setThreadValueOverrides(finalState.values as Partial<AgentThreadState>);
+          toast.error("本轮生成未能完成，已同步当前对话内容，可重新发起请求。");
+        }
+
+        // Changing the controlled thread id clears only the local SDK stream
+        // (it does not cancel the already-terminal backend run). Switching it
+        // back immediately makes useStream fetch the persisted messages, so
+        // the page exits the false loading state without a manual refresh.
+        setOnStreamThreadId(null);
+        refreshTimer = window.setTimeout(() => {
+          if (!disposed && threadIdRef.current === activeThreadId) {
+            setOnStreamThreadId(activeThreadId);
+          }
+        }, 0);
+      } catch {
+        // A transient status lookup failure must not disrupt a real stream;
+        // the next polling interval will try again if it is still quiet.
+      } finally {
+        if (!disposed) {
+          streamReconciliationInFlightRef.current = false;
+        }
+      }
+    };
+
+    const interval = window.setInterval(
+      () => void reconcileRun(),
+      STREAM_RECONCILIATION_POLL_MS,
+    );
+
+    return () => {
+      disposed = true;
+      window.clearInterval(interval);
+      if (refreshTimer !== null) {
+        window.clearTimeout(refreshTimer);
+      }
+    };
+  }, [isMock, onStreamThreadId, queryClient, thread.isLoading]);
 
   // Reset thread-local pending UI state when the caller actually switches AWAY
   // from a thread (threadId becomes nullish). This is the "click 新对话 / open
@@ -909,13 +951,13 @@ export function useThreadStream({
   // clearing optimistic messages in that case is exactly what made submitted
   // questions visually disappear — the live run that just started would be
   // aborted by the very effect intended to reset stale state.
-  useEffect(() => {
-    if (threadId != null) {
-      // Forward direction: starting or continuing with a real thread.
-      // No reset needed; the upstream useStream will load history for this id.
-      setThreadValueOverrides({});
-      return;
-    }
+  useEffect(() => {
+    if (threadId != null) {
+      // Forward direction: starting or continuing with a real thread.
+      // No reset needed; the upstream useStream will load history for this id.
+      setThreadValueOverrides({});
+      return;
+    }
     const prevThread = threadStreamRef.current;
     if (prevThread?.isLoading) {
       try {
@@ -927,89 +969,89 @@ export function useThreadStream({
     startedRef.current = false;
     sendInFlightRef.current = false;
     prevMsgCountRef.current = 0;
-    setOptimisticMessages([]);
-    setIsUploading(false);
-    setThreadValueOverrides({});
-  }, [threadId]);
-
-  useEffect(() => {
-    const activeThreadId = threadIdRef.current ?? onStreamThreadId ?? null;
-    const effectiveTitleProvisional =
-      (threadValueOverrides.title_provisional ??
-        thread.values?.title_provisional) === true;
-
-    if (!activeThreadId || thread.isLoading || !effectiveTitleProvisional) {
-      return;
-    }
-
-    let cancelled = false;
-    let timeoutId: ReturnType<typeof setTimeout> | null = null;
-    const controller = new AbortController();
-
-    const poll = async () => {
-      while (!cancelled) {
-        try {
-          const nextState = await fetchThreadTitleRefreshState(
-            activeThreadId,
-            controller.signal,
-          );
-          if (cancelled || !nextState) {
-            return;
-          }
-
-          setThreadValueOverrides((prev) => ({
-            ...prev,
-            title: nextState.title,
-            title_provisional: nextState.title_provisional,
-          }));
-
-          if (nextState.title) {
-            updateCachedThreadLists(queryClient, (threads) =>
-              threads.map((t) =>
-                t.thread_id === activeThreadId
-                  ? {
-                      ...t,
-                      values: {
-                        ...t.values,
-                        title: nextState.title,
-                        title_provisional: nextState.title_provisional,
-                      },
-                    }
-                  : t,
-              ),
-            );
-          }
-
-          if (nextState.title_provisional !== true) {
-            void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
-            return;
-          }
-        } catch {
-          return;
-        }
-
-        await new Promise<void>((resolve) => {
-          timeoutId = setTimeout(resolve, 2000);
-        });
-      }
-    };
-
-    void poll();
-
-    return () => {
-      cancelled = true;
-      controller.abort();
-      if (timeoutId) {
-        clearTimeout(timeoutId);
-      }
-    };
-  }, [
-    onStreamThreadId,
-    queryClient,
-    thread.isLoading,
-    thread.values?.title_provisional,
-    threadValueOverrides.title_provisional,
-  ]);
+    setOptimisticMessages([]);
+    setIsUploading(false);
+    setThreadValueOverrides({});
+  }, [threadId]);
+
+  useEffect(() => {
+    const activeThreadId = threadIdRef.current ?? onStreamThreadId ?? null;
+    const effectiveTitleProvisional =
+      (threadValueOverrides.title_provisional ??
+        thread.values?.title_provisional) === true;
+
+    if (!activeThreadId || thread.isLoading || !effectiveTitleProvisional) {
+      return;
+    }
+
+    let cancelled = false;
+    let timeoutId: ReturnType<typeof setTimeout> | null = null;
+    const controller = new AbortController();
+
+    const poll = async () => {
+      while (!cancelled) {
+        try {
+          const nextState = await fetchThreadTitleRefreshState(
+            activeThreadId,
+            controller.signal,
+          );
+          if (cancelled || !nextState) {
+            return;
+          }
+
+          setThreadValueOverrides((prev) => ({
+            ...prev,
+            title: nextState.title,
+            title_provisional: nextState.title_provisional,
+          }));
+
+          if (nextState.title) {
+            updateCachedThreadLists(queryClient, (threads) =>
+              threads.map((t) =>
+                t.thread_id === activeThreadId
+                  ? {
+                      ...t,
+                      values: {
+                        ...t.values,
+                        title: nextState.title,
+                        title_provisional: nextState.title_provisional,
+                      },
+                    }
+                  : t,
+              ),
+            );
+          }
+
+          if (nextState.title_provisional !== true) {
+            void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
+            return;
+          }
+        } catch {
+          return;
+        }
+
+        await new Promise<void>((resolve) => {
+          timeoutId = setTimeout(resolve, 2000);
+        });
+      }
+    };
+
+    void poll();
+
+    return () => {
+      cancelled = true;
+      controller.abort();
+      if (timeoutId) {
+        clearTimeout(timeoutId);
+      }
+    };
+  }, [
+    onStreamThreadId,
+    queryClient,
+    thread.isLoading,
+    thread.values?.title_provisional,
+    threadValueOverrides.title_provisional,
+  ]);
 
   // Clear optimistic when server messages arrive (count increases)
   useEffect(() => {
@@ -1196,71 +1238,71 @@ export function useThreadStream({
           }),
         );
 
-        const mergedContext = {
-          ...context,
-          ...extraContext,
-        };
-        const selectedLlmWikiIds = Array.isArray(
-          mergedContext.llmwiki_knowledge_base_ids,
-        )
-          ? mergedContext.llmwiki_knowledge_base_ids
-          : [];
-        const ragModeEnabled =
-          localSettings.display.ragModeEnabled ||
-          isThreadRagModeLocked(threadId) ||
-          selectedLlmWikiIds.length > 0;
-        if (ragModeEnabled) {
-          lockThreadRagMode(threadId);
-        }
+        const mergedContext = {
+          ...context,
+          ...extraContext,
+        };
+        const selectedLlmWikiIds = Array.isArray(
+          mergedContext.llmwiki_knowledge_base_ids,
+        )
+          ? mergedContext.llmwiki_knowledge_base_ids
+          : [];
+        const ragModeEnabled =
+          localSettings.display.ragModeEnabled ||
+          isThreadRagModeLocked(threadId) ||
+          selectedLlmWikiIds.length > 0;
+        if (ragModeEnabled) {
+          lockThreadRagMode(threadId);
+        }
 
         const contextCompressionEnabled =
           localSettings.display.contextCompressionEnabled ?? false;
 
-        const hiddenContextMessages = normalizeHiddenContextMessages(options);
-        const submittedMessages: Message[] = [
-          ...hiddenContextMessages.map((item) => ({
-            type: "human" as const,
-            ...(item.name ? { name: item.name } : {}),
-            content: [
-              {
-                type: "text" as const,
-                text: item.text,
-              },
-            ],
-            additional_kwargs: {
-              ...item.additionalKwargs,
-              hide_from_ui: true,
-            },
-          })),
-          {
-            type: "human" as const,
-            content: [
-              {
-                type: "text" as const,
-                text,
-              },
-            ],
-            additional_kwargs: {
-              ...options?.additionalKwargs,
-              client_ts: clientTs,
-              ...(filesForSubmit.length > 0
-                ? { files: filesForSubmit }
-                : {}),
-            },
-          },
-        ];
-
-        await thread.submit(
-          {
-            messages: submittedMessages,
-          },
-          {
-            threadId: threadId,
-            streamSubgraphs: true,
-            streamResumable: true,
-            onDisconnect: runOptions?.onDisconnect,
-            multitaskStrategy: runOptions?.multitaskStrategy,
-            config: {
+        const hiddenContextMessages = normalizeHiddenContextMessages(options);
+        const submittedMessages: Message[] = [
+          ...hiddenContextMessages.map((item) => ({
+            type: "human" as const,
+            ...(item.name ? { name: item.name } : {}),
+            content: [
+              {
+                type: "text" as const,
+                text: item.text,
+              },
+            ],
+            additional_kwargs: {
+              ...item.additionalKwargs,
+              hide_from_ui: true,
+            },
+          })),
+          {
+            type: "human" as const,
+            content: [
+              {
+                type: "text" as const,
+                text,
+              },
+            ],
+            additional_kwargs: {
+              ...options?.additionalKwargs,
+              client_ts: clientTs,
+              ...(filesForSubmit.length > 0
+                ? { files: filesForSubmit }
+                : {}),
+            },
+          },
+        ];
+
+        await thread.submit(
+          {
+            messages: submittedMessages,
+          },
+          {
+            threadId: threadId,
+            streamSubgraphs: true,
+            streamResumable: true,
+            onDisconnect: runOptions?.onDisconnect,
+            multitaskStrategy: runOptions?.multitaskStrategy,
+            config: {
               recursion_limit: 1000,
             },
             context: {
@@ -1287,59 +1329,59 @@ export function useThreadStream({
           },
         );
         void queryClient.invalidateQueries({ queryKey: ["threads", "search"] });
-      } catch (error) {
-        const message =
-          error instanceof Error ? error.message : String(error);
-        const friendly = friendlySendLimitMessage(message);
-        if (friendly) {
-          setOptimisticMessages((messages) => {
-            const human = messages.find((item) => item.type === "human");
-            const kept = human ? [human] : [];
-            return [
-              ...kept,
-              {
-                type: "ai",
-                id: `opt-ai-limit-${Date.now()}`,
-                content: friendly,
-                additional_kwargs: { element: "task" },
-              } as Message,
-            ];
-          });
-          setIsUploading(false);
-          return;
-        }
-        setOptimisticMessages([]);
-        setIsUploading(false);
-        throw error;
-      } finally {
+      } catch (error) {
+        const message =
+          error instanceof Error ? error.message : String(error);
+        const friendly = friendlySendLimitMessage(message);
+        if (friendly) {
+          setOptimisticMessages((messages) => {
+            const human = messages.find((item) => item.type === "human");
+            const kept = human ? [human] : [];
+            return [
+              ...kept,
+              {
+                type: "ai",
+                id: `opt-ai-limit-${Date.now()}`,
+                content: friendly,
+                additional_kwargs: { element: "task" },
+              } as Message,
+            ];
+          });
+          setIsUploading(false);
+          return;
+        }
+        setOptimisticMessages([]);
+        setIsUploading(false);
+        throw error;
+      } finally {
         sendInFlightRef.current = false;
       }
     },
-    [thread, _handleOnStart, t.uploads.uploadingFiles, context, localSettings.display.ragModeEnabled, queryClient, runOptions],
+    [thread, _handleOnStart, t.uploads.uploadingFiles, context, localSettings.display.ragModeEnabled, queryClient, runOptions],
   );
 
   // Merge thread with optimistic messages for display
-  const mergedValues =
-    Object.keys(threadValueOverrides).length > 0
-      ? {
-          ...thread.values,
-          ...threadValueOverrides,
-        }
-      : thread.values;
-
-  const mergedMessages =
-    Array.isArray(mergedValues.messages)
-      ? (mergedValues.messages as Message[])
-      : thread.messages;
-
-  const mergedThread =
-    optimisticMessages.length > 0 || mergedValues !== thread.values
-      ? ({
-          ...thread,
-          values: mergedValues,
-          messages: [...mergedMessages, ...optimisticMessages],
-        } as typeof thread)
-      : thread;
+  const mergedValues =
+    Object.keys(threadValueOverrides).length > 0
+      ? {
+          ...thread.values,
+          ...threadValueOverrides,
+        }
+      : thread.values;
+
+  const mergedMessages =
+    Array.isArray(mergedValues.messages)
+      ? (mergedValues.messages as Message[])
+      : thread.messages;
+
+  const mergedThread =
+    optimisticMessages.length > 0 || mergedValues !== thread.values
+      ? ({
+          ...thread,
+          values: mergedValues,
+          messages: [...mergedMessages, ...optimisticMessages],
+        } as typeof thread)
+      : thread;
 
   // 第 4 个返回值 `onStreamThreadId` = 底层 useStream 当前实际绑定的线程 id（新建/未保存时为 null）。
   // 调用方据此判断「流是否已切到全新线程」，避免在切换会话的那一帧把消息发进上一个会话
@@ -1595,8 +1637,8 @@ export function useDeleteThread() {
  * `MessageList`) so the removal shows immediately; a reload then reads the
  * persisted, already-trimmed state.
  */
-export function useDeleteMessage() {
-  return useMutation({
+export function useDeleteMessage() {
+  return useMutation({
     mutationFn: async ({
       threadId,
       messageId,
@@ -1626,92 +1668,92 @@ export function useDeleteMessage() {
       // Fall back to the requested id so the caller can always hide something.
       return body.deleted_ids?.length ? body.deleted_ids : [messageId];
     },
-  });
-}
-
-/**
- * Clear all messages from a thread checkpoint. The caller should immediately
- * hide the returned ids locally because the active stream cache may still hold
- * the old message objects until a reload/refetch reads the trimmed checkpoint.
- */
-export function useClearThreadMessages() {
-  return useMutation({
-    mutationFn: async ({
-      threadId,
-    }: {
-      threadId: string;
-    }): Promise<string[]> => {
-      const response = await apiFetch(
-        `${getBackendBaseURL()}/api/threads/${encodeURIComponent(
-          threadId,
-        )}/messages`,
-        {
-          method: "DELETE",
-        },
-      );
-
-      if (!response.ok) {
-        const error = await response
-          .json()
-          .catch(() => ({ detail: "清空对话失败。" }));
-        throw new Error(error.detail ?? "清空对话失败。");
-      }
-
-      const body = (await response.json().catch(() => ({}))) as {
-        deleted_ids?: string[];
-      };
-      return body.deleted_ids ?? [];
-    },
-  });
-}
-
-/**
- * Persist an in-place message edit in the latest thread checkpoint.
- *
- * This is opt-in UI behaviour: most chat pages keep their existing
- * "edit question and resubmit" affordance, while position roundtable can pass
- * this mutation down to save the original message content itself.
- */
-export function useEditMessage() {
-  return useMutation({
-    mutationFn: async ({
-      threadId,
-      messageId,
-      content,
-    }: {
-      threadId: string;
-      messageId: string;
-      content: string;
-    }): Promise<Message> => {
-      const response = await apiFetch(
-        `${getBackendBaseURL()}/api/threads/${encodeURIComponent(
-          threadId,
-        )}/messages/${encodeURIComponent(messageId)}`,
-        {
-          method: "PATCH",
-          headers: { "Content-Type": "application/json" },
-          body: JSON.stringify({ content }),
-        },
-      );
-
-      if (!response.ok) {
-        const error = await response
-          .json()
-          .catch(() => ({ detail: "消息保存失败。" }));
-        throw new Error(error.detail ?? "消息保存失败。");
-      }
-
-      const body = (await response.json().catch(() => ({}))) as {
-        message?: Message;
-      };
-      return body.message ?? ({ id: messageId, type: "human", content } as Message);
-    },
-  });
-}
-
-/**
- * Merge metadata into a conversation's record via the Gateway
- * `PATCH /api/threads/{id}` route. Used to persist per-conversation flags such
+  });
+}
+
+/**
+ * Clear all messages from a thread checkpoint. The caller should immediately
+ * hide the returned ids locally because the active stream cache may still hold
+ * the old message objects until a reload/refetch reads the trimmed checkpoint.
+ */
+export function useClearThreadMessages() {
+  return useMutation({
+    mutationFn: async ({
+      threadId,
+    }: {
+      threadId: string;
+    }): Promise<string[]> => {
+      const response = await apiFetch(
+        `${getBackendBaseURL()}/api/threads/${encodeURIComponent(
+          threadId,
+        )}/messages`,
+        {
+          method: "DELETE",
+        },
+      );
+
+      if (!response.ok) {
+        const error = await response
+          .json()
+          .catch(() => ({ detail: "清空对话失败。" }));
+        throw new Error(error.detail ?? "清空对话失败。");
+      }
+
+      const body = (await response.json().catch(() => ({}))) as {
+        deleted_ids?: string[];
+      };
+      return body.deleted_ids ?? [];
+    },
+  });
+}
+
+/**
+ * Persist an in-place message edit in the latest thread checkpoint.
+ *
+ * This is opt-in UI behaviour: most chat pages keep their existing
+ * "edit question and resubmit" affordance, while position roundtable can pass
+ * this mutation down to save the original message content itself.
+ */
+export function useEditMessage() {
+  return useMutation({
+    mutationFn: async ({
+      threadId,
+      messageId,
+      content,
+    }: {
+      threadId: string;
+      messageId: string;
+      content: string;
+    }): Promise<Message> => {
+      const response = await apiFetch(
+        `${getBackendBaseURL()}/api/threads/${encodeURIComponent(
+          threadId,
+        )}/messages/${encodeURIComponent(messageId)}`,
+        {
+          method: "PATCH",
+          headers: { "Content-Type": "application/json" },
+          body: JSON.stringify({ content }),
+        },
+      );
+
+      if (!response.ok) {
+        const error = await response
+          .json()
+          .catch(() => ({ detail: "消息保存失败。" }));
+        throw new Error(error.detail ?? "消息保存失败。");
+      }
+
+      const body = (await response.json().catch(() => ({}))) as {
+        message?: Message;
+      };
+      return body.message ?? ({ id: messageId, type: "human", content } as Message);
+    },
+  });
+}
+
+/**
+ * Merge metadata into a conversation's record via the Gateway
+ * `PATCH /api/threads/{id}` route. Used to persist per-conversation flags such
  * as `is_pinned` (置顶) and `is_favorite` (收藏) — a conversation belongs to a
  * single user, so these live directly on the thread metadata (no join table).
  * Updates the `["threads", "search"]` cache optimistically so the UI reflects
@@ -1787,29 +1829,29 @@ export function useRenameThread() {
     mutationFn: async ({
       threadId,
       title,
-    }: {
-      threadId: string;
-      title: string;
-    }) => {
-      await apiClient.threads.updateState(threadId, {
-        values: { title, title_provisional: false },
-      });
-    },
-    onSuccess(_, { threadId, title }) {
-      updateCachedThreadLists(queryClient, (threads) =>
-        threads.map((t) =>
+    }: {
+      threadId: string;
+      title: string;
+    }) => {
+      await apiClient.threads.updateState(threadId, {
+        values: { title, title_provisional: false },
+      });
+    },
+    onSuccess(_, { threadId, title }) {
+      updateCachedThreadLists(queryClient, (threads) =>
+        threads.map((t) =>
           t.thread_id === threadId
             ? {
                 ...t,
-                values: {
-                  ...t.values,
-                  title,
-                  title_provisional: false,
-                },
-              }
-            : t,
-        ),
-      );
+                values: {
+                  ...t.values,
+                  title,
+                  title_provisional: false,
+                },
+              }
+            : t,
+        ),
+      );
     },
   });
 }
diff --git a/frontend-web/src/core/threads/thread-access-error.ts b/frontend-web/src/core/threads/thread-access-error.ts
index dd803081..4b01f74f 100644
--- a/frontend-web/src/core/threads/thread-access-error.ts
+++ b/frontend-web/src/core/threads/thread-access-error.ts
@@ -62,6 +62,37 @@ export function isThreadNotAccessibleError(message: string): boolean {
   );
 }
 
+export function isAbortLikeError(error: unknown): boolean {
+  if (error instanceof DOMException && error.name === "AbortError") {
+    return true;
+  }
+  if (error instanceof Error && error.name === "AbortError") {
+    return true;
+  }
+  const message = getStreamErrorMessage(error).toLowerCase();
+  return (
+    message.includes("aborterror") ||
+    message.includes("the operation was aborted") ||
+    message.includes("bodystreambuffer")
+  );
+}
+
+export function isTransientStreamTransportError(message: string): boolean {
+  const lowered = message.toLowerCase();
+  return (
+    /failed to fetch/i.test(message) ||
+    lowered.includes("networkerror") ||
+    lowered.includes("network error") ||
+    lowered.includes("load failed") ||
+    lowered.includes("err_connection") ||
+    lowered.includes("err_incomplete") ||
+    lowered.includes("err_network") ||
+    lowered.includes("econnreset") ||
+    lowered.includes("econnaborted") ||
+    /fetch failed/i.test(message)
+  );
+}
+
 /** Build a label for the *current* logged-in identity (email → user_id → 未知). */
 export function buildCurrentUserLabel(): string {
   const auth = getStoredAuth();
diff --git a/frontend-web/src/eightbf-roundtable/components/EightBfStep1Workspace.tsx b/frontend-web/src/eightbf-roundtable/components/EightBfStep1Workspace.tsx
index 3ca451a2..2af55a28 100644
--- a/frontend-web/src/eightbf-roundtable/components/EightBfStep1Workspace.tsx
+++ b/frontend-web/src/eightbf-roundtable/components/EightBfStep1Workspace.tsx
@@ -167,14 +167,27 @@ export function EightBfStep1Sidebar({
   taskCard,
   businessChain,
   intentReady,
+  onCollapse,
 }: {
   taskCard?: ReactNode;
   businessChain?: ReactNode;
   intentReady: object | null;
+  onCollapse?: () => void;
 }) {
   return (
     <div className="eightbf-roundtable__step1-sidebar position-roundtable-entry-sidebar">
       {taskCard}
+      {onCollapse && !taskCard && (
+        <button
+          type="button"
+          className="position-roundtable-intent-config-collapse-btn ml-auto"
+          onClick={onCollapse}
+          aria-label="收起左侧面板"
+          title="收起左侧面板"
+        >
+          <img src={collapsePanelIcon} alt="" aria-hidden="true" />
+        </button>
+      )}
       <EightBfIntentDelivery intentReady={intentReady} businessChain={businessChain} />
     </div>
   );
diff --git a/frontend-web/src/eightbf-roundtable/pages/EightBfRoundtablePage.tsx b/frontend-web/src/eightbf-roundtable/pages/EightBfRoundtablePage.tsx
index ed99b6e3..870fa65e 100644
--- a/frontend-web/src/eightbf-roundtable/pages/EightBfRoundtablePage.tsx
+++ b/frontend-web/src/eightbf-roundtable/pages/EightBfRoundtablePage.tsx
@@ -267,6 +267,7 @@ export default function EightBfRoundtablePage({ compactChrome = false }: { compa
       newTaskLabel="新建会话"
       hideDefaultStep1RightSidebar
       step2HeaderTitle={`${configuredChain?.title || "8BF 业务链"} · 多智能体会商`}
+      step3HeaderTitle={`${configuredChain?.title || "8BF 业务链"} · 方案总结`}
       renderStep1={(props) => (
         <EightBfStep1Panel
           {...props}
@@ -275,15 +276,17 @@ export default function EightBfRoundtablePage({ compactChrome = false }: { compa
           onConfigureChain={openChainSettings}
         />
       )}
-      renderStep1LeftSidebar={({ intentReady }) => (
+      renderStep1LeftSidebar={({ intentReady, onCollapse, submittedSeatKeys, onSeatClick }) => (
         <EightBfStep1Sidebar
           intentReady={intentReady}
+          onCollapse={onCollapse}
           taskCard={taskId ? (
             <EightBfTaskCard
               task={task}
               dictionaries={taskDictionaries}
               loading={taskLoading}
               error={taskError}
+              onCollapse={onCollapse}
             />
           ) : undefined}
           businessChain={
@@ -291,6 +294,8 @@ export default function EightBfRoundtablePage({ compactChrome = false }: { compa
               chain={configuredChain}
               loading={isLoading}
               embedded
+              submittedSeatKeys={submittedSeatKeys}
+              onSeatClick={onSeatClick}
               className="position-roundtable-intent-delivery-flow eightbf-roundtable__business-chain-flow"
             />
           }
diff --git a/frontend-web/src/eightbf-roundtable/styles/step3.css b/frontend-web/src/eightbf-roundtable/styles/step3.css
index 35936ad7..9e0ab901 100644
--- a/frontend-web/src/eightbf-roundtable/styles/step3.css
+++ b/frontend-web/src/eightbf-roundtable/styles/step3.css
@@ -76,22 +76,70 @@
   background: #21958a;
 }
 
-/* 第三步只保留「总结报告 + 沙箱」。沿用第一、二步的 4px 面板语言。 */
-.dark .eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable__step3-source-panel {
-  border: 1px solid rgb(43 143 254 / 50%);
-  border-radius: 4px;
-  background: #032650;
-  padding: 12px;
+/* 第三步：8BF 左栏与第一步相同，对话区去掉原外层圆角白框，沿用第一、二步深蓝面板。 */
+.dark .eightbf-roundtable[data-roundtable-step="3"] > main {
+  padding: 12px 0;
 }
 
-.dark .eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable__step3-report-panel {
+.dark .eightbf-roundtable[data-roundtable-step="3"] > main[data-step2-sidebar-expanded="true"] {
+  gap: 0;
+}
+
+.dark .eightbf-roundtable[data-roundtable-step="3"] > main[data-step2-sidebar-expanded="false"] {
+  gap: 10px;
+}
+
+.dark .eightbf-roundtable[data-roundtable-step="3"] #middle-viewport {
   border-color: rgb(43 143 254 / 50%);
-  border-radius: 4px !important;
+  border-radius: 4px;
   background: #032650;
   box-shadow: none;
 }
 
+.dark .eightbf-roundtable[data-roundtable-step="3"] #left-sidebar[data-sidebar-expanded="true"] {
+  width: 374px;
+  padding: 0 12px;
+}
+
+.dark .eightbf-roundtable[data-roundtable-step="3"] #left-sidebar[data-sidebar-expanded="false"] {
+  width: 80px;
+  padding: 0 12px;
+}
+
+.eightbf-roundtable .eightbf-roundtable-step3-chat {
+  min-height: 0;
+  background: #032650;
+}
+
+.eightbf-roundtable .eightbf-roundtable-step3-log {
+  background: #032650;
+  border: 0;
+  box-shadow: none;
+}
+
+.eightbf-roundtable .eightbf-roundtable-step3-chat .position-roundtable-intent-header-actions button:disabled {
+  cursor: not-allowed;
+  opacity: 0.55;
+}
+
+.eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable-step3-log .text-slate-700,
+.eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable-step3-log .text-slate-500 {
+  color: #aaceff;
+}
+
+.eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable-step3-log .text-slate-400 {
+  color: #8aa0c4;
+}
+
 /* PositionIntentInput is the shared Step 1/2 composer; Step 3 uses the exact same frame. */
 .dark .eightbf-roundtable[data-roundtable-step="3"] .eightbf-roundtable-step3-input {
   flex: 0 0 auto;
 }
+
+@media (max-width: 1280px) {
+  .dark .eightbf-roundtable[data-roundtable-step="3"] #left-sidebar[data-sidebar-expanded="true"] { width: 326px; }
+}
+
+@media (max-width: 1024px) {
+  .dark .eightbf-roundtable[data-roundtable-step="3"] #left-sidebar[data-sidebar-expanded="true"] { width: 294px; }
+}
diff --git a/frontend-web/src/position-roundtable/components/PositionBusinessChainFlow.tsx b/frontend-web/src/position-roundtable/components/PositionBusinessChainFlow.tsx
index d3d85eff..5b65efbd 100644
--- a/frontend-web/src/position-roundtable/components/PositionBusinessChainFlow.tsx
+++ b/frontend-web/src/position-roundtable/components/PositionBusinessChainFlow.tsx
@@ -5,7 +5,7 @@
  * 不会读取或写入岗位会商的会话、岗位节点状态。
  */
 import { useRef, useState } from "react";
-import { CheckCircle2, Circle, Search } from "lucide-react";
+import { Check, Search } from "lucide-react";
 
 import {
   Dialog,
@@ -34,6 +34,14 @@ export interface PositionBusinessChainFlowProps {
    * border and background; this flow keeps only its title row and canvas.
    */
   embedded?: boolean;
+  /**
+   * Identity keys of seats whose Markdown artifact has been submitted.
+   * Matched against `seat.agent_id` and `seat.name` (case-insensitive).
+   * Green filled check = submitted only, same as 岗位会商 `is-delivered`.
+   */
+  submittedSeatKeys?: readonly string[];
+  /** Click a seat node. Host opens the deliverable dialog when a submission exists. */
+  onSeatClick?: (seat: ChainSeat) => void;
 }
 
 function getFlowStages(chain: BusinessChain): FlowStage[] {
@@ -51,13 +59,27 @@ function getFlowStages(chain: BusinessChain): FlowStage[] {
   return chain.seats.map((seat) => ({ goal: null, seats: [seat] }));
 }
 
+function isSeatSubmitted(seat: ChainSeat, submittedSeatKeys: ReadonlySet<string>): boolean {
+  return submittedSeatKeys.has(seat.agent_id.trim().toLowerCase())
+    || submittedSeatKeys.has((seat.name ?? "").trim().toLowerCase());
+}
+
 export function PositionBusinessChainFlow({
   chain,
   loading = false,
   className,
   embedded = false,
+  submittedSeatKeys,
+  onSeatClick,
 }: PositionBusinessChainFlowProps) {
   const [dialogOpen, setDialogOpen] = useState(false);
+  const submittedKeys = new Set(
+    (submittedSeatKeys ?? []).map((key) => key.trim().toLowerCase()).filter(Boolean),
+  );
+  const handleSeatClick = (seat: ChainSeat) => {
+    onSeatClick?.(seat);
+    setDialogOpen(false);
+  };
 
   return (
     <section
@@ -112,14 +134,26 @@ export function PositionBusinessChainFlow({
         </div>
       ) : (
         <>
-          <BusinessChainCanvas chain={chain} embedded={embedded} className="min-h-0 flex-1" />
+          <BusinessChainCanvas
+            chain={chain}
+            embedded={embedded}
+            submittedKeys={submittedKeys}
+            onSeatClick={onSeatClick ? handleSeatClick : undefined}
+            className="min-h-0 flex-1"
+          />
           <Dialog open={dialogOpen} onOpenChange={setDialogOpen}>
             <DialogContent className="flex h-[86vh] w-[96vw] max-w-[1180px] flex-col gap-0 overflow-hidden p-0">
               <DialogHeader className="shrink-0 border-b px-5 py-4 dark:border-[#2b8ffe]/25">
                 <DialogTitle className="text-base font-semibold">{chain.title} · 业务链条流程图</DialogTitle>
               </DialogHeader>
               <div className="min-h-0 flex-1 p-4">
-                <BusinessChainCanvas chain={chain} expanded className="h-full" />
+                <BusinessChainCanvas
+                  chain={chain}
+                  expanded
+                  submittedKeys={submittedKeys}
+                  onSeatClick={onSeatClick ? handleSeatClick : undefined}
+                  className="h-full"
+                />
               </div>
             </DialogContent>
           </Dialog>
@@ -133,11 +167,15 @@ function BusinessChainCanvas({
   chain,
   expanded = false,
   embedded = false,
+  submittedKeys,
+  onSeatClick,
   className,
 }: {
   chain: BusinessChain;
   expanded?: boolean;
   embedded?: boolean;
+  submittedKeys: ReadonlySet<string>;
+  onSeatClick?: (seat: ChainSeat) => void;
   className?: string;
 }) {
   const [view, setView] = useState({ tx: 0, ty: 0 });
@@ -175,6 +213,7 @@ function BusinessChainCanvas({
       onDoubleClick={() => setView({ tx: 0, ty: 0 })}
       onPointerDown={(event) => {
         if (event.button !== 0) return;
+        if ((event.target as HTMLElement | null)?.closest?.(".pr-flow-card")) return;
         dragRef.current = { x: event.clientX, y: event.clientY, tx: view.tx, ty: view.ty };
         setPanning(true);
         event.currentTarget.setPointerCapture(event.pointerId);
@@ -217,6 +256,8 @@ function BusinessChainCanvas({
                       accent={accent}
                       width={nodeWidth}
                       compact={embedded}
+                      completed={isSeatSubmitted(seat, submittedKeys)}
+                      onClick={onSeatClick ? () => onSeatClick(seat) : undefined}
                     />
                   );
                 })}
@@ -277,6 +318,7 @@ function FlowNode({
   completed = false,
   width,
   compact = false,
+  onClick,
 }: {
   title: string;
   description: string;
@@ -284,25 +326,27 @@ function FlowNode({
   completed?: boolean;
   width: number;
   compact?: boolean;
+  onClick?: () => void;
 }) {
-  const StatusIcon = completed ? CheckCircle2 : Circle;
-  return (
-    <article
-      className={cn(
-        "relative overflow-hidden rounded-xl border border-slate-200 bg-white p-3 pr-10 shadow-sm dark:border-[#2b8ffe]/40 dark:bg-[#0a2d58]",
-        compact && "rounded-lg",
-      )}
-      style={{ width, borderLeftWidth: 5, borderLeftColor: accent }}
-    >
+  const className = cn(
+    "pr-flow-card relative overflow-hidden rounded-xl border border-slate-200 bg-white p-3 pr-10 text-left font-[inherit] shadow-sm dark:border-[#2b8ffe]/40 dark:bg-[#0a2d58]",
+    compact && "rounded-lg",
+    completed && "border-[#36b987]/60",
+    onClick && "cursor-pointer transition hover:-translate-y-0.5 hover:shadow-md",
+  );
+  const style = { width, borderLeftWidth: 5, borderLeftColor: accent };
+  const body = (
+    <>
       <span
         className={cn(
-          "absolute right-2 top-2 flex size-6 items-center justify-center rounded-full border bg-white shadow-sm dark:bg-[#0d3768]",
+          "absolute right-2 top-2 grid size-5 place-items-center rounded-full",
           completed
-            ? "border-emerald-500 text-emerald-500"
-            : "border-slate-300 text-slate-400 dark:border-[#8aa0c4] dark:text-[#8aa0c4]",
+            ? "border-0 bg-[#36b987] text-white"
+            : "border-2 border-[#78a7e8] bg-transparent text-white",
         )}
+        title={completed ? "已完成" : "待提交"}
       >
-        <StatusIcon className="size-3.5" strokeWidth={2.5} />
+        {completed ? <Check className="size-3" strokeWidth={3} /> : null}
       </span>
       <p className="truncate text-sm font-extrabold leading-5 text-slate-900 dark:text-[#e8edf5]" title={title}>
         {title}
@@ -310,6 +354,25 @@ function FlowNode({
       <p className="mt-0.5 truncate text-xs font-semibold leading-4" style={{ color: accent }} title={description}>
         {description}
       </p>
+    </>
+  );
+  if (onClick) {
+    return (
+      <button
+        type="button"
+        className={className}
+        style={style}
+        title={completed ? "已完成 · 点击查看产物" : "点击查看产物"}
+        onClick={onClick}
+        onPointerDown={(event) => event.stopPropagation()}
+      >
+        {body}
+      </button>
+    );
+  }
+  return (
+    <article className={className} style={style}>
+      {body}
     </article>
   );
 }
diff --git a/frontend-web/src/roundtable-planning/components/HighFidelityReport.tsx b/frontend-web/src/roundtable-planning/components/HighFidelityReport.tsx
index 79d9fc76..34d98be8 100644
--- a/frontend-web/src/roundtable-planning/components/HighFidelityReport.tsx
+++ b/frontend-web/src/roundtable-planning/components/HighFidelityReport.tsx
@@ -59,6 +59,8 @@ interface SeatDelivery {
 }
 
 interface HighFidelityReportProps {
+  useStep1Chrome?: boolean;
+  headerTitle?: string;
   threadIds: ThreadIdMap | null;
   coordinatorName: string | null;
   /** The most recent leader-agent text — rendered as the final consensus. */
@@ -120,6 +122,8 @@ function formatGeneratedAt(d: Date): string {
 }
 
 export const HighFidelityReport: React.FC<HighFidelityReportProps> = ({
+  useStep1Chrome = false,
+  headerTitle,
   threadIds,
   coordinatorName,
   consensusText,
@@ -433,6 +437,8 @@ export const HighFidelityReport: React.FC<HighFidelityReportProps> = ({
   if (summaryMode) {
     return (
       <Step3SummaryMode
+        useStep1Chrome={useStep1Chrome}
+        headerTitle={headerTitle}
         threadIds={threadIds}
         coordinatorName={coordinatorName}
         consensusText={consensusText}
diff --git a/frontend-web/src/roundtable-planning/components/Step3Panel.tsx b/frontend-web/src/roundtable-planning/components/Step3Panel.tsx
index 6b309355..36b271c9 100644
--- a/frontend-web/src/roundtable-planning/components/Step3Panel.tsx
+++ b/frontend-web/src/roundtable-planning/components/Step3Panel.tsx
@@ -23,6 +23,9 @@ import { useMemo } from "react";
 import type { TaskArtifactSubmissionController } from "@/roundtable-planning/lib/task-artifact-submission";
 
 export interface Step3PanelProps {
+  /** 8BF 第三步对话区与第一、二步共用深蓝顶栏；默认不改变原会商。 */
+  useStep1Chrome?: boolean;
+  headerTitle?: string;
   threadIds: ThreadIdMap | null;
   coordinatorName: string | null;
   consensusText: string;
@@ -60,6 +63,8 @@ export interface Step3PanelProps {
 
 export function Step3Panel(props: Step3PanelProps) {
   const {
+    useStep1Chrome = false,
+    headerTitle,
     threadIds,
     coordinatorName,
     consensusText,
@@ -108,6 +113,8 @@ export function Step3Panel(props: Step3PanelProps) {
 
   return (
     <HighFidelityReport
+      useStep1Chrome={useStep1Chrome}
+      headerTitle={headerTitle}
       threadIds={threadIds}
       coordinatorName={coordinatorName}
       consensusText={consensusText}
diff --git a/frontend-web/src/roundtable-planning/components/Step3SummaryMode.tsx b/frontend-web/src/roundtable-planning/components/Step3SummaryMode.tsx
index 0c04a4a5..94921a96 100644
--- a/frontend-web/src/roundtable-planning/components/Step3SummaryMode.tsx
+++ b/frontend-web/src/roundtable-planning/components/Step3SummaryMode.tsx
@@ -59,6 +59,8 @@ interface SeatDelivery {
 }
 
 interface Step3SummaryModeProps {
+  useStep1Chrome?: boolean;
+  headerTitle?: string;
   threadIds: ThreadIdMap | null;
   coordinatorName: string | null;
   consensusText: string;
@@ -81,6 +83,8 @@ interface Step3SummaryModeProps {
 type SourceModal = "consensus" | "seats" | "files" | null;
 
 export function Step3SummaryMode({
+  useStep1Chrome = false,
+  headerTitle,
   threadIds,
   coordinatorName,
   consensusText,
@@ -208,34 +212,37 @@ export function Step3SummaryMode({
 
   return (
     <div className="flex h-full min-h-0 flex-col text-slate-800">
-      {/* 顶栏 */}
-      <div className="shrink-0 flex items-center justify-between gap-3 border-b border-slate-100 bg-gradient-to-r from-slate-50 to-white px-6 py-3.5 flex-wrap">
-        <div className="flex items-center gap-2.5">
-          <Sparkles className="w-5 h-5 text-primary" />
-          <h3 className="text-sm font-black text-slate-900 tracking-tight">方案总结 · 报告</h3>
-          <span className="inline-flex items-center gap-1.5 text-[10px] font-bold text-primary bg-[var(--brand-200)]/60 border border-red-200/50 px-2 py-0.5 rounded-full">
-            {(phase === "creating" || phase === "streaming") && (
-              <Loader2 className="w-3 h-3 animate-spin" />
-            )}
-            {phase === "done" && <CheckCircle className="w-3 h-3 text-emerald-600" />}
-            {statusLabel}
-          </span>
+      {/* 顶栏。8BF 改走对话区内的第一步同款顶栏，这里不再套一层。 */}
+      {!useStep1Chrome && (
+        <div className="shrink-0 flex items-center justify-between gap-3 border-b border-slate-100 bg-gradient-to-r from-slate-50 to-white px-6 py-3.5 flex-wrap">
+          <div className="flex items-center gap-2.5">
+            <Sparkles className="w-5 h-5 text-primary" />
+            <h3 className="text-sm font-black text-slate-900 tracking-tight">方案总结 · 报告</h3>
+            <span className="inline-flex items-center gap-1.5 text-[10px] font-bold text-primary bg-[var(--brand-200)]/60 border border-red-200/50 px-2 py-0.5 rounded-full">
+              {(phase === "creating" || phase === "streaming") && (
+                <Loader2 className="w-3 h-3 animate-spin" />
+              )}
+              {phase === "done" && <CheckCircle className="w-3 h-3 text-emerald-600" />}
+              {statusLabel}
+            </span>
+          </div>
+          <div className="flex items-center gap-2">
+            <button
+              type="button"
+              onClick={() => redraw()}
+              disabled={phase === "creating" || phase === "streaming"}
+              className="bg-white border border-slate-200 text-slate-700 hover:bg-slate-50 disabled:opacity-50 disabled:cursor-not-allowed text-[10.5px] font-bold px-3 py-1.5 rounded-xl flex items-center gap-1 transition"
+            >
+              <RefreshCw className="w-3.5 h-3.5 text-slate-500" />
+              重新生成
+            </button>
+          </div>
         </div>
-        <div className="flex items-center gap-2">
-          <button
-            type="button"
-            onClick={() => redraw()}
-            disabled={phase === "creating" || phase === "streaming"}
-            className="bg-white border border-slate-200 text-slate-700 hover:bg-slate-50 disabled:opacity-50 disabled:cursor-not-allowed text-[10.5px] font-bold px-3 py-1.5 rounded-xl flex items-center gap-1 transition"
-          >
-            <RefreshCw className="w-3.5 h-3.5 text-slate-500" />
-            重新生成
-          </button>
-        </div>
-      </div>
+      )}
 
-      {/* 主体：左源卡 + 右沙箱 */}
-      <div className="flex-1 min-h-0 flex gap-3 p-3">
+      {/* 主体：左源卡 + 右沙箱。8BF 左栏改用第一步任务/意图区，这里只留对话面板。 */}
+      <div className={cn("flex-1 min-h-0 flex", !useStep1Chrome && "gap-3 p-3")}>
+        {!useStep1Chrome && (
         <aside
           data-step3-source-panel
           className={cn(
@@ -317,11 +324,16 @@ export function Step3SummaryMode({
             </>
           )}
         </aside>
+        )}
 
         {/* 右栏：智能体进度 + Markdown 沙箱（复用第 2 步）。 */}
         <section
           data-step3-report-panel
-          className="eightbf-roundtable__step3-report-panel relative flex-1 min-w-0 rounded-2xl border border-slate-200/60 bg-white overflow-hidden"
+          className={cn(
+            "relative flex-1 min-w-0 overflow-hidden",
+            !useStep1Chrome &&
+              "eightbf-roundtable__step3-report-panel rounded-2xl border border-slate-200/60 bg-white",
+          )}
         >
           <Step2SandboxLayout
             activeThreadId={activeArtifactThreadId ?? summaryThreadId}
@@ -330,6 +342,8 @@ export function Step3SummaryMode({
             taskArtifactSubmission={taskArtifactSubmission}
           >
             <AgentProgressPanel
+              useStep1Chrome={useStep1Chrome}
+              headerTitle={headerTitle}
               phase={phase}
               dialogues={displayDialogues}
               error={error}
@@ -453,6 +467,8 @@ function CollapsedSourceCard({
 // ── 右栏：智能体进度面板（沙箱的 60% 区域）+ 底部对话输入框 ──────────────────
 
 function AgentProgressPanel({
+  useStep1Chrome = false,
+  headerTitle,
   phase,
   dialogues,
   error,
@@ -468,6 +484,8 @@ function AgentProgressPanel({
   setSelectedModel,
   taskArtifactSubmission,
 }: {
+  useStep1Chrome?: boolean;
+  headerTitle?: string;
   phase: UseStep3SummaryReturn["phase"];
   dialogues: UseStep3SummaryReturn["dialogues"];
   error: string | null;
@@ -524,22 +542,53 @@ function AgentProgressPanel({
   };
 
   return (
-    <div className="flex h-full min-h-0 flex-col bg-slate-50/20">
-      <div className="shrink-0 flex items-center gap-2 border-b border-slate-100 bg-white px-4 py-2.5">
-        <div className="flex items-center gap-2 min-w-0">
-          <div className="w-6 h-6 shrink-0 rounded-lg bg-gradient-to-tr from-primary to-[var(--brand-200)] flex items-center justify-center text-white text-xs shadow-sm">
-            报
+    <div
+      className={cn(
+        "flex h-full min-h-0 flex-col",
+        useStep1Chrome
+          ? "position-roundtable-intent-panel eightbf-roundtable-intent-panel eightbf-roundtable-step3-chat"
+          : "bg-slate-50/20",
+      )}
+    >
+      {useStep1Chrome ? (
+        <div className="shrink-0 flex items-center justify-between gap-3">
+          <div className="position-roundtable-intent-header-title">
+            <span aria-hidden="true" />
+            <h2>{headerTitle || "方案总结"}</h2>
           </div>
-          <div className="leading-tight min-w-0">
-            <div className="text-xs font-bold text-slate-800 truncate">方案总结报告智能体</div>
-            <div className="text-[10px] text-slate-400 truncate">据各席位成果撰写 Markdown 总结报告</div>
+          <div className="position-roundtable-intent-header-actions">
+            <button
+              type="button"
+              onClick={onRetry}
+              disabled={phase === "creating" || phase === "streaming"}
+            >
+              重新生成
+            </button>
           </div>
         </div>
-      </div>
+      ) : (
+        <div className="shrink-0 flex items-center gap-2 border-b border-slate-100 bg-white px-4 py-2.5">
+          <div className="flex items-center gap-2 min-w-0">
+            <div className="w-6 h-6 shrink-0 rounded-lg bg-gradient-to-tr from-primary to-[var(--brand-200)] flex items-center justify-center text-white text-xs shadow-sm">
+              报
+            </div>
+            <div className="leading-tight min-w-0">
+              <div className="text-xs font-bold text-slate-800 truncate">方案总结报告智能体</div>
+              <div className="text-[10px] text-slate-400 truncate">据各席位成果撰写 Markdown 总结报告</div>
+            </div>
+          </div>
+        </div>
+      )}
 
       {/* 消息列表 —— 与第 2 步同款气泡（流式正文 + 工具步骤卡 + 文件卡）。 */}
       <div className="relative flex-1 min-h-0">
-        <div ref={scrollRef} className="size-full overflow-y-auto overflow-x-hidden p-4 space-y-4 bg-white">
+        <div
+          ref={scrollRef}
+          className={cn(
+            "size-full overflow-y-auto overflow-x-hidden p-4 space-y-4",
+            useStep1Chrome ? "eightbf-roundtable-step3-log" : "bg-white",
+          )}
+        >
           {phase === "creating" && dialogues.length === 0 && (
             <div className="flex items-center gap-2 text-xs text-slate-500">
               <Loader2 className="w-3.5 h-3.5 animate-spin text-primary" />
diff --git a/frontend-web/src/roundtable-planning/hooks/useTaskArtifactSubmission.ts b/frontend-web/src/roundtable-planning/hooks/useTaskArtifactSubmission.ts
index 7dfbca9d..ce413a3c 100644
--- a/frontend-web/src/roundtable-planning/hooks/useTaskArtifactSubmission.ts
+++ b/frontend-web/src/roundtable-planning/hooks/useTaskArtifactSubmission.ts
@@ -193,6 +193,13 @@ export function useTaskArtifactSubmission(
     return operation;
   }, [config, resolveTarget]);
 
+  const submittedRecords = useMemo(
+    () => Object.values(entries)
+      .filter((entry) => entry.state === "submitted" && entry.record?.submitted)
+      .map((entry) => entry.record as RoundtableArtifactSubmissionRecord),
+    [entries],
+  );
+
   return useMemo(() => {
     if (!config) return undefined;
     return {
@@ -202,6 +209,7 @@ export function useTaskArtifactSubmission(
       stateFor: (target) => entries[recordKey(resolveTarget(target))]?.state || "idle",
       errorFor: (target) => entries[recordKey(resolveTarget(target))]?.error || null,
       submit,
+      submittedRecords,
     } satisfies TaskArtifactSubmissionController;
-  }, [config, entries, resolveTarget, submit]);
+  }, [config, entries, resolveTarget, submit, submittedRecords]);
 }
diff --git a/frontend-web/src/roundtable-planning/lib/match-seat-submission.ts b/frontend-web/src/roundtable-planning/lib/match-seat-submission.ts
new file mode 100644
index 00000000..297a4f5d
--- /dev/null
+++ b/frontend-web/src/roundtable-planning/lib/match-seat-submission.ts
@@ -0,0 +1,92 @@
+import type { RoundtableArtifactSubmissionRecord } from "@/roundtable-planning/api/artifact-submissions";
+import type { ThreadIdMap } from "@/roundtable-planning/api/multi-agent";
+import type { ChainSeat } from "@/roundtable-planning/lib/business-chain";
+import { getDisplayNameFor, type SelectedAgent } from "@/roundtable-planning/lib/roundtable-constants";
+
+function norm(value: string | null | undefined): string {
+  return (value ?? "").trim().toLowerCase();
+}
+
+function sourceKeyOf(record: RoundtableArtifactSubmissionRecord): string {
+  const raw = (record.artifact.sourceKey ?? "").trim();
+  if (!raw || raw.toLowerCase().startsWith("thread:")) return "";
+  return raw;
+}
+
+/**
+ * Match a chain seat to a submitted Markdown artifact.
+ *
+ * Submissions are keyed by the graph agent name (`threadIds` key) or UUID;
+ * chain seats expose both `agent_id` and display `name`.
+ */
+export function findSeatSubmission(
+  seat: ChainSeat,
+  records: RoundtableArtifactSubmissionRecord[],
+  selectedAgents: SelectedAgent[],
+  threadIds: ThreadIdMap | null,
+): RoundtableArtifactSubmissionRecord | null {
+  const selected = selectedAgents.find((agent) => agent.agent_id === seat.agent_id);
+  const aliases = new Set(
+    [
+      seat.agent_id,
+      seat.name,
+      selected?.agent_id,
+      selected?.name,
+      selected ? getDisplayNameFor(selected) : "",
+    ]
+      .map(norm)
+      .filter(Boolean),
+  );
+
+  const hits = records.filter((record) => {
+    if (!record.submitted) return false;
+    const sourceKey = norm(sourceKeyOf(record));
+    if (sourceKey && aliases.has(sourceKey)) return true;
+    if (!threadIds) return false;
+    const owner = Object.entries(threadIds).find(([, id]) => id === record.artifact.threadId)?.[0];
+    if (owner && aliases.has(norm(owner))) return true;
+    for (const alias of aliases) {
+      const mapped = threadIds[alias];
+      if (mapped && mapped === record.artifact.threadId) return true;
+    }
+    const byName = threadIds[seat.name] ?? (selected ? threadIds[selected.name] : undefined);
+    return Boolean(byName && byName === record.artifact.threadId);
+  });
+
+  if (hits.length === 0) return null;
+  return hits
+    .slice()
+    .sort((a, b) => (b.submittedAt ?? "").localeCompare(a.submittedAt ?? ""))[0] ?? null;
+}
+
+/** Identity keys the flowchart can match against `seat.agent_id` / `seat.name`. */
+export function submittedSeatKeysFor(
+  seats: ChainSeat[],
+  records: RoundtableArtifactSubmissionRecord[],
+  selectedAgents: SelectedAgent[],
+  threadIds: ThreadIdMap | null,
+): string[] {
+  const keys = new Set<string>();
+  for (const record of records) {
+    if (!record.submitted) continue;
+    const sourceKey = sourceKeyOf(record);
+    if (sourceKey) keys.add(norm(sourceKey));
+    if (threadIds) {
+      const owner = Object.entries(threadIds).find(([, id]) => id === record.artifact.threadId)?.[0];
+      if (owner) keys.add(norm(owner));
+    }
+  }
+  for (const seat of seats) {
+    if (!findSeatSubmission(seat, records, selectedAgents, threadIds)) continue;
+    keys.add(norm(seat.agent_id));
+    if (seat.name) keys.add(norm(seat.name));
+  }
+  for (const agent of selectedAgents) {
+    const seat = { agent_id: agent.agent_id, name: agent.name };
+    if (!findSeatSubmission(seat, records, selectedAgents, threadIds)) continue;
+    keys.add(norm(agent.agent_id));
+    keys.add(norm(agent.name));
+    keys.add(norm(getDisplayNameFor(agent)));
+  }
+  return [...keys];
+}
diff --git a/frontend-web/src/roundtable-planning/lib/task-artifact-submission.ts b/frontend-web/src/roundtable-planning/lib/task-artifact-submission.ts
index d9a1d5e1..de257493 100644
--- a/frontend-web/src/roundtable-planning/lib/task-artifact-submission.ts
+++ b/frontend-web/src/roundtable-planning/lib/task-artifact-submission.ts
@@ -37,4 +37,6 @@ export interface TaskArtifactSubmissionController {
   stateFor: (target: TaskArtifactTarget) => TaskArtifactSubmissionState;
   errorFor: (target: TaskArtifactTarget) => string | null;
   submit: (target: TaskArtifactTarget) => Promise<RoundtableArtifactSubmissionRecord | null>;
+  /** Task-scoped ledger rows that have been formally submitted. */
+  submittedRecords: RoundtableArtifactSubmissionRecord[];
 }
diff --git a/frontend-web/src/roundtable-planning/pages/RoundtablePlanningPage.tsx b/frontend-web/src/roundtable-planning/pages/RoundtablePlanningPage.tsx
index 7a03cbc6..e3ea2bfe 100644
--- a/frontend-web/src/roundtable-planning/pages/RoundtablePlanningPage.tsx
+++ b/frontend-web/src/roundtable-planning/pages/RoundtablePlanningPage.tsx
@@ -135,6 +135,7 @@ import {
 import {
   buildChainSeatSelection,
   type BusinessChain,
+  type ChainSeat,
   type SeatSelectionResult,
 } from "@/roundtable-planning/lib/business-chain";
 import { DEFAULT_SEAT_MODE, type SeatMode } from "@/roundtable-planning/lib/seat-mode";
@@ -156,6 +157,14 @@ import { emitWujieEvent, isWujieEnv, onWujieEvent, readWujieProps } from "@/core
 import { collectRoundtableDeliverables } from "@/roundtable-planning/lib/roundtable-deliverables";
 import { useTaskArtifactSubmission } from "@/roundtable-planning/hooks/useTaskArtifactSubmission";
 import type { TaskArtifactSubmissionConfig } from "@/roundtable-planning/lib/task-artifact-submission";
+import {
+  findSeatSubmission,
+  submittedSeatKeysFor,
+} from "@/roundtable-planning/lib/match-seat-submission";
+import {
+  AnalysisResultDetailDialog,
+  type AnalysisResultCardItem,
+} from "@/components/analysis-results";
 
 /**
  * 业务码 → 任务工作区业务码（``TaskBusiness``），用于深链 taskId 模式底部「快捷跳转」栏
@@ -320,6 +329,7 @@ export default function RoundtablePlanningPage({
   hideDefaultStep1RightSidebar = false,
   step2HeaderTitle,
   step2HeaderRightSlot,
+  step3HeaderTitle,
   /** 独立业务页的工作区品牌区，取代通用步骤导航。 */
   headerLeftSlot,
   /** 放在历史记录后面的独立业务操作或状态。 */
@@ -353,7 +363,12 @@ export default function RoundtablePlanningPage({
     step2SeatStubMessages: Record<string, unknown[]>;
     step3Summary: DraftStep3SummarySnapshot | null;
   }) => ReactNode;
-  renderStep1LeftSidebar?: (context: { intentReady: object | null }) => ReactNode;
+  renderStep1LeftSidebar?: (context: {
+    intentReady: object | null;
+    onCollapse?: () => void;
+    submittedSeatKeys?: string[];
+    onSeatClick?: (seat: ChainSeat) => void;
+  }) => ReactNode;
   renderStep2LeftSidebarHeader?: (context: {
     intentReady: object | null;
     onCollapse: () => void;
@@ -363,6 +378,8 @@ export default function RoundtablePlanningPage({
   step2HeaderTitle?: string;
   /** 8BF 第二步顶栏右侧附加操作（如返回）。 */
   step2HeaderRightSlot?: ReactNode;
+  /** 8BF 第三步对话区标题，与第一、二步顶栏同一套样式。 */
+  step3HeaderTitle?: string;
   headerLeftSlot?: ReactNode;
   headerActionAfterHistory?: ReactNode;
   hideHeaderSaveDraft?: boolean;
@@ -482,11 +499,11 @@ export default function RoundtablePlanningPage({
       consensusEmittedRef.current = true;
     }
   }, [inWujieEmbed]);
-  // 带 taskId 时，先按任务回显最新草稿再决定是否 autoStart。用 state 而非 ref：
+  // 带存储键 / 深链 taskId 时，先回显最新草稿再决定是否 autoStart。用 state 而非 ref：
   // 解析完成需触发重渲染让 C2 effect 重跑（否则 intentThreadId 先就绪会错过 autoStart）。
-  // 无 taskId 时初始即「已解析」，autoStart 照常。
+  // 无存储键时初始即「已解析」，autoStart 照常。8BF 走 storageTaskId，不依赖 prefill.taskId。
   const [taskRestoreResolved, setTaskRestoreResolved] = useState<boolean>(
-    !prefillRef.current?.taskId,
+    !draftStorageTaskId,
   );
   // 深链/预填自动会话：进入页面后要先建意图线程、（带 taskId 时）回显历史草稿，这段时间
   // 页面只有一句欢迎语、问答还没真正开始，线程创建慢时像卡住。下面这个标志用来在超时后
@@ -742,6 +759,58 @@ export default function RoundtablePlanningPage({
     step2.agentNameToRole,
   );
 
+  const [seatDeliverable, setSeatDeliverable] = useState<AnalysisResultCardItem | null>(null);
+  const submittedRecords = taskArtifactSubmission?.submittedRecords;
+  const submittedSeatKeys = useMemo(
+    () => submittedSeatKeysFor(
+      step2.selectedAgents.map((agent) => ({ agent_id: agent.agent_id, name: agent.name })),
+      submittedRecords ?? [],
+      step2.selectedAgents,
+      step2.threadIds,
+    ),
+    [submittedRecords, step2.selectedAgents, step2.threadIds],
+  );
+  const handleChainSeatClick = useCallback((seat: ChainSeat) => {
+    const record = findSeatSubmission(
+      seat,
+      submittedRecords ?? [],
+      step2.selectedAgents,
+      step2.threadIds,
+    );
+    if (!record) {
+      triggerToast("该节点暂无可预览产物");
+      return;
+    }
+    setSeatDeliverable({
+      id: record.id,
+      agentName: seat.name || record.artifact.sourceKey,
+      productName: record.artifact.name,
+      positionName: seat.description?.trim() || autoChainResult?.chain?.title || "业务链席位",
+      delivered: true,
+      artifactPath: record.artifact.path,
+      artifactMimeType: record.artifact.mimeType,
+      artifactThreadId: record.artifact.threadId,
+      updatedAt: record.submittedAt ?? undefined,
+    });
+  }, [
+    autoChainResult?.chain?.title,
+    step2.selectedAgents,
+    step2.threadIds,
+    submittedRecords,
+    triggerToast,
+  ]);
+  const renderStep1LeftSidebarWithDeliveries = useMemo(
+    () => (renderStep1LeftSidebar
+      ? (context: { intentReady: object | null; onCollapse?: () => void }) =>
+        renderStep1LeftSidebar({
+          ...context,
+          submittedSeatKeys,
+          onSeatClick: taskArtifactSubmission ? handleChainSeatClick : undefined,
+        })
+      : undefined),
+    [handleChainSeatClick, renderStep1LeftSidebar, submittedSeatKeys, taskArtifactSubmission],
+  );
+
   // 同步 step1StateRef,让 buildInitialIntent / Persona / Step 3 都能读到最新值。
   useEffect(() => {
     step1StateRef.current = {
@@ -1287,11 +1356,11 @@ export default function RoundtablePlanningPage({
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, []);
 
-  // C1.5（无界回显）：带 taskId 时，挂载即按任务取最新草稿回显。命中 → 抑制 autoStart
+  // C1.5（无界 / 8BF 回显）：带存储键时，挂载即取最新草稿回显。命中 → 抑制 autoStart
   // （避免重复发首条消息）；未命中 → 放行 autoStart 走全新任务。只跑一次。
   useEffect(() => {
-    // 回显聊天记录按存储键（xdfx-A=行动id），与 useDraftPersistence 的 taskId 保持一致。
-    const tid = recordTaskIdOf(prefillRef.current);
+    // 回显聊天记录按存储键：8BF 用独立 `storageTaskId`；xdfx-A 按行动id；其它深链按真实 taskId。
+    const tid = draftStorageTaskId;
     if (!tid) return;
     let cancelled = false;
     void (async () => {
@@ -2218,6 +2287,15 @@ export default function RoundtablePlanningPage({
         }}
       />
 
+      {taskArtifactSubmission && (
+        <AnalysisResultDetailDialog
+          item={seatDeliverable}
+          onOpenChange={(open) => {
+            if (!open) setSeatDeliverable(null);
+          }}
+        />
+      )}
+
       {showToast && (
         <div className="fixed top-4 left-1/2 transform -translate-x-1/2 z-50 bg-primary text-white text-xs px-4 py-2.5 rounded-xl shadow-lg border border-primary/40 font-medium flex items-center gap-2 animate-bounce">
           <Sparkles className="h-4 w-4 shrink-0" />
@@ -2371,7 +2449,9 @@ export default function RoundtablePlanningPage({
         setSidebarExpanded={setStep2SidebarExpanded}
       />
       <main
-        data-step2-sidebar-expanded={currentStep === 2 ? String(step2SidebarExpanded) : undefined}
+        data-step2-sidebar-expanded={
+          currentStep === 2 || currentStep === 3 ? String(step2SidebarExpanded) : undefined
+        }
         className="relative z-0 flex-1 overflow-hidden p-4 flex gap-4 min-h-0"
       >
         {/* LEFT SIDEBAR */}
@@ -2399,7 +2479,7 @@ export default function RoundtablePlanningPage({
           lockBusinessChain={lockBusinessChain}
           entryRailBusinessChainSlot={entryRailBusinessChainSlot}
           entryRailTaskCardSlot={entryRailTaskCardSlot}
-          renderStep1LeftSidebar={renderStep1LeftSidebar}
+          renderStep1LeftSidebar={renderStep1LeftSidebarWithDeliveries}
           renderStep2LeftSidebarHeader={renderStep2LeftSidebarHeader}
         />
 
@@ -2496,6 +2576,8 @@ export default function RoundtablePlanningPage({
 
           {currentStep === 3 && (
             <Step3Panel
+              useStep1Chrome={rootClassName?.includes("eightbf-roundtable") ?? false}
+              headerTitle={step3HeaderTitle}
               threadIds={step2.threadIds}
               coordinatorName={step2.coordinatorName}
               consensusText={step2.lastLeaderContent}
@@ -2933,7 +3015,12 @@ interface LeftSidebarProps {
   /** 第一阶段由独立业务页提供的自定义任务卡片。 */
   entryRailTaskCardSlot?: ReactNode;
   /** 独立业务页替换第一步左侧工作区；仅提供已解析的意图状态。 */
-  renderStep1LeftSidebar?: (context: { intentReady: object | null }) => ReactNode;
+  renderStep1LeftSidebar?: (context: {
+    intentReady: object | null;
+    onCollapse?: () => void;
+    submittedSeatKeys?: string[];
+    onSeatClick?: (seat: ChainSeat) => void;
+  }) => ReactNode;
   /** 独立业务页在第二步左栏顶部复用任务与意图区。 */
   renderStep2LeftSidebarHeader?: (context: {
     intentReady: object | null;
@@ -2952,13 +3039,21 @@ function Step2SandboxSidebarSync({
 }) {
   const { open } = useArtifacts();
   const prevOpenRef = useRef(open);
+  const prevStepRef = useRef(currentStep);
 
   useEffect(() => {
-    if (currentStep !== 2) {
+    const enteredCollapsibleStep =
+      (currentStep === 2 || currentStep === 3) &&
+      prevStepRef.current !== currentStep;
+    prevStepRef.current = currentStep;
+
+    if (currentStep !== 2 && currentStep !== 3) {
       prevOpenRef.current = open;
       return;
     }
-    if (open && !prevOpenRef.current && sidebarExpanded) {
+    const openedNow = open && !prevOpenRef.current;
+    const landedWithSandbox = enteredCollapsibleStep && open;
+    if ((openedNow || landedWithSandbox) && sidebarExpanded) {
       setSidebarExpanded(false);
     }
     prevOpenRef.current = open;
@@ -3002,9 +3097,38 @@ function LeftSidebar({
   const toggleSeatFilter = (filter: SeatFilter) =>
     setSeatFilter((cur) => (cur === filter ? null : filter));
 
-  // Step 3 隐藏左侧栏(原「参与与结论贡献」列),让中间「最终方案展示」自适应
-  // 撑满整行宽度(右侧栏在 Step !==1 时也已 return null)。
-  if (currentStep === 3) return null;
+  // Step 3：通用会商隐藏左栏以让方案展示撑满；8BF 复用第一步左栏，并和第二步一样可收起。
+  if (currentStep === 3) {
+    if (!renderStep1LeftSidebar) return null;
+    return (
+      <section
+        ref={dzRef}
+        id="left-sidebar"
+        data-sidebar-expanded={String(sidebarExpanded)}
+        className={cn(
+          "min-h-0 shrink-0 flex flex-col gap-3 pr-1 transition-[width] duration-200 ease-out overflow-y-auto",
+          sidebarExpanded ? "w-[280px]" : "w-[80px]",
+        )}
+      >
+        {!sidebarExpanded ? (
+          <button
+            type="button"
+            onClick={() => setSidebarExpanded(true)}
+            title="展开侧栏"
+            aria-expanded={false}
+            className="w-full shrink-0 flex h-10 items-center justify-center rounded-[4px] border border-slate-200/50 bg-white text-slate-500 hover:text-primary hover:border-primary/30 transition-colors shadow-[0_2px_8px_rgba(0,0,0,0.01)]"
+          >
+            <PanelLeftOpen className="h-4 w-4" />
+          </button>
+        ) : (
+          renderStep1LeftSidebar({
+            intentReady,
+            onCollapse: () => setSidebarExpanded(false),
+          })
+        )}
+      </section>
+    );
+  }
 
   return (
     <section
diff --git a/offline-backend-20260512/backend/app/gateway/routers/artifacts.py b/offline-backend-20260512/backend/app/gateway/routers/artifacts.py
index 0bf0935e..b5738d00 100644
--- a/offline-backend-20260512/backend/app/gateway/routers/artifacts.py
+++ b/offline-backend-20260512/backend/app/gateway/routers/artifacts.py
@@ -36,6 +36,27 @@ EDITABLE_TEXT_SUFFIXES = {
     ".log",
 }
 
+_VIRTUAL_USER_DATA_PREFIX = "mnt/user-data"
+
+
+def coerce_artifact_virtual_path(path: str) -> str:
+    """Normalize an artifacts URL path to a sandbox virtual path.
+
+    Streaming write previews may request a bare filename such as
+    ``未命名文件.md`` before the model has emitted a real
+    ``/mnt/user-data/outputs/...`` path. Mapping a single path segment into
+    the thread outputs directory turns that into a normal 404 (file not written
+    yet) instead of HTTP 400 ``Path must start with /mnt/user-data``.
+    """
+    stripped = path.strip().lstrip("/").replace("\\", "/")
+    if not stripped:
+        raise HTTPException(status_code=400, detail="Path must start with /mnt/user-data")
+    if stripped == _VIRTUAL_USER_DATA_PREFIX or stripped.startswith(_VIRTUAL_USER_DATA_PREFIX + "/"):
+        return stripped
+    if "/" in stripped or stripped in {".", ".."}:
+        raise HTTPException(status_code=400, detail="Path must start with /mnt/user-data")
+    return f"{_VIRTUAL_USER_DATA_PREFIX}/outputs/{stripped}"
+
 
 class ArtifactUpdateRequest(BaseModel):
     content: str
@@ -198,6 +219,7 @@ async def get_artifact(thread_id: str, path: str, request: Request, download: bo
         - Download file: `/api/threads/abc123/artifacts/mnt/user-data/outputs/data.csv?download=true`
         - Active web content such as `.html`, `.xhtml`, and `.svg` artifacts is always downloaded
     """
+    path = coerce_artifact_virtual_path(path)
     # Check if this is a request for a file inside a .skill archive (e.g., xxx.skill/SKILL.md)
     if ".skill/" in path:
         # Split the path at ".skill/" to get the ZIP file path and internal path
@@ -285,6 +307,7 @@ async def update_artifact(
     if ".skill/" in path:
         raise HTTPException(status_code=400, detail="Skill archive contents are read-only.")
 
+    path = coerce_artifact_virtual_path(path)
     actual_path = await aresolve_thread_virtual_path(thread_id, path)
     logger.info(f"Updating artifact path: thread_id={thread_id}, requested_path={path}, actual_path={actual_path}")