feat: add inline citations and thread management features

Citations:
- Add citations parsing utilities for extracting source references from AI responses
- Render inline citations as hover card badges in message content
- Display citation cards with title, URL, and description on hover
- Add citation badge rendering in artifact markdown preview
- Update prompt to guide AI to output citations in correct format

Thread Management:
- Add rename functionality for chat threads with dialog UI
- Add share functionality to copy thread link to clipboard
- Share links use Vercel URL for production accessibility
- Add useRenameThread hook for thread title updates

i18n:
- Add translations for rename, share, cancel, save, and linkCopied

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/components/workspace/artifacts/artifact-file-detail.tsx

@@ -2,6 +2,7 @@ import {
   Code2Icon,
   CopyIcon,
   DownloadIcon,
+  ExternalLinkIcon,
   EyeIcon,
   SquareArrowOutUpRightIcon,
   XIcon,
@@ -18,6 +19,13 @@ import {
   ArtifactHeader,
   ArtifactTitle,
 } from "@/components/ai-elements/artifact";
+import {
+  InlineCitationCard,
+  InlineCitationCardBody,
+  InlineCitationSource,
+} from "@/components/ai-elements/inline-citation";
+import { Badge } from "@/components/ui/badge";
+import { HoverCardTrigger } from "@/components/ui/hover-card";
 import { Select, SelectItem } from "@/components/ui/select";
 import {
   SelectContent,
@@ -29,6 +37,7 @@ import { ToggleGroup, ToggleGroupItem } from "@/components/ui/toggle-group";
 import { CodeEditor } from "@/components/workspace/code-editor";
 import { useArtifactContent } from "@/core/artifacts/hooks";
 import { urlOfArtifact } from "@/core/artifacts/utils";
+import { extractDomainFromUrl } from "@/core/citations";
 import { useI18n } from "@/core/i18n/hooks";
 import { checkCodeFile, getFileName } from "@/core/utils/files";
 import { cn } from "@/lib/utils";
@@ -216,7 +225,38 @@ export function ArtifactFilePreview({
   if (language === "markdown") {
     return (
       <div className="size-full px-4">
-        <Streamdown className="size-full">{content ?? ""}</Streamdown>
+        <Streamdown
+          className="size-full"
+          components={{
+            a: ({
+              href,
+              children,
+            }: React.AnchorHTMLAttributes<HTMLAnchorElement>) => {
+              if (!href) {
+                return <span>{children}</span>;
+              }
+
+              // Check if it's an external link (http/https)
+              const isExternalLink =
+                href.startsWith("http://") || href.startsWith("https://");
+
+              if (isExternalLink) {
+                return (
+                  <ExternalLinkBadge href={href}>{children}</ExternalLinkBadge>
+                );
+              }
+
+              // Internal/anchor link
+              return (
+                <a href={href} className="text-primary hover:underline">
+                  {children}
+                </a>
+              );
+            },
+          }}
+        >
+          {content ?? ""}
+        </Streamdown>
       </div>
     );
   }
@@ -230,3 +270,51 @@ export function ArtifactFilePreview({
   }
   return null;
 }
+
+/**
+ * External link badge component for artifact preview
+ */
+function ExternalLinkBadge({
+  href,
+  children,
+}: {
+  href: string;
+  children: React.ReactNode;
+}) {
+  const domain = extractDomainFromUrl(href);
+
+  return (
+    <InlineCitationCard>
+      <HoverCardTrigger asChild>
+        <a
+          href={href}
+          target="_blank"
+          rel="noopener noreferrer"
+          className="inline-flex items-center"
+        >
+          <Badge
+            variant="secondary"
+            className="mx-0.5 cursor-pointer gap-1 rounded-full px-2 py-0.5 text-xs font-normal hover:bg-secondary/80"
+          >
+            {children ?? domain}
+            <ExternalLinkIcon className="size-3" />
+          </Badge>
+        </a>
+      </HoverCardTrigger>
+      <InlineCitationCardBody>
+        <div className="p-3">
+          <InlineCitationSource title={domain} url={href} />
+          <a
+            href={href}
+            target="_blank"
+            rel="noopener noreferrer"
+            className="text-primary mt-2 inline-flex items-center gap-1 text-xs hover:underline"
+          >
+            Visit source
+            <ExternalLinkIcon className="size-3" />
+          </a>
+        </div>
+      </InlineCitationCardBody>
+    </InlineCitationCard>
+  );
+}

frontend/src/components/workspace/messages/message-list-item.tsx

@@ -1,14 +1,28 @@
 import type { Message } from "@langchain/langgraph-sdk";
+import { ExternalLinkIcon, LinkIcon } from "lucide-react";
 import { useParams } from "next/navigation";
 import { memo, useMemo } from "react";
 
+import {
+  InlineCitationCard,
+  InlineCitationCardBody,
+  InlineCitationSource,
+} from "@/components/ai-elements/inline-citation";
 import {
   Message as AIElementMessage,
   MessageContent as AIElementMessageContent,
   MessageResponse as AIElementMessageResponse,
   MessageToolbar,
 } from "@/components/ai-elements/message";
+import { Badge } from "@/components/ui/badge";
+import { HoverCardTrigger } from "@/components/ui/hover-card";
 import { resolveArtifactURL } from "@/core/artifacts/utils";
+import {
+  type Citation,
+  buildCitationMap,
+  extractDomainFromUrl,
+  parseCitations,
+} from "@/core/citations";
 import {
   extractContentFromMessage,
   extractReasoningContentFromMessage,
@@ -68,20 +82,63 @@ function MessageContent_({
   isLoading?: boolean;
 }) {
   const rehypePlugins = useRehypeSplitWordsIntoSpans(isLoading);
-  const content = useMemo(() => {
+
+  // Extract and parse citations from message content
+  const { citations, cleanContent } = useMemo(() => {
     const reasoningContent = extractReasoningContentFromMessage(message);
-    const content = extractContentFromMessage(message);
-    if (!isLoading && reasoningContent && !content) {
-      return reasoningContent;
+    const rawContent = extractContentFromMessage(message);
+    if (!isLoading && reasoningContent && !rawContent) {
+      return { citations: [], cleanContent: reasoningContent };
     }
-    return content;
+    return parseCitations(rawContent ?? "");
   }, [isLoading, message]);
+
+  // Build citation map for quick URL lookup
+  const citationMap = useMemo(
+    () => buildCitationMap(citations),
+    [citations],
+  );
+
   const { thread_id } = useParams<{ thread_id: string }>();
+
   return (
     <AIElementMessageContent className={className}>
+      {/* Citations list at the top */}
+      {citations.length > 0 && <CitationsList citations={citations} />}
+
       <AIElementMessageResponse
         rehypePlugins={rehypePlugins}
         components={{
+          a: ({
+            href,
+            children,
+          }: React.AnchorHTMLAttributes<HTMLAnchorElement>) => {
+            if (!href) {
+              return <span>{children}</span>;
+            }
+
+            // Check if this link matches a citation
+            const citation = citationMap.get(href);
+            if (citation) {
+              return (
+                <CitationLink citation={citation} href={href}>
+                  {children}
+                </CitationLink>
+              );
+            }
+
+            // Regular external link
+            return (
+              <a
+                href={href}
+                target="_blank"
+                rel="noopener noreferrer"
+                className="text-primary underline underline-offset-2 hover:no-underline"
+              >
+                {children}
+              </a>
+            );
+          },
           img: ({ src, alt }: React.ImgHTMLAttributes<HTMLImageElement>) => {
             if (!src) return null;
             if (typeof src !== "string") {
@@ -109,9 +166,131 @@ function MessageContent_({
           },
         }}
       >
-        {content}
+        {cleanContent}
       </AIElementMessageResponse>
     </AIElementMessageContent>
   );
 }
+
+/**
+ * Citations list component that displays all sources at the top
+ */
+function CitationsList({ citations }: { citations: Citation[] }) {
+  if (citations.length === 0) return null;
+
+  return (
+    <div className="mb-4 rounded-lg border bg-muted/30 p-3">
+      <div className="mb-2 flex items-center gap-2 text-sm font-medium text-muted-foreground">
+        <LinkIcon className="size-4" />
+        <span>Sources ({citations.length})</span>
+      </div>
+      <div className="flex flex-wrap gap-2">
+        {citations.map((citation) => (
+          <CitationBadge key={citation.id} citation={citation} />
+        ))}
+      </div>
+    </div>
+  );
+}
+
+/**
+ * Single citation badge in the citations list
+ */
+function CitationBadge({ citation }: { citation: Citation }) {
+  const domain = extractDomainFromUrl(citation.url);
+
+  return (
+    <InlineCitationCard>
+      <HoverCardTrigger asChild>
+        <a
+          href={citation.url}
+          target="_blank"
+          rel="noopener noreferrer"
+          className="inline-flex"
+        >
+          <Badge
+            variant="secondary"
+            className="cursor-pointer gap-1 rounded-full px-2.5 py-1 text-xs font-normal hover:bg-secondary/80"
+          >
+            {domain}
+            <ExternalLinkIcon className="size-3" />
+          </Badge>
+        </a>
+      </HoverCardTrigger>
+      <InlineCitationCardBody>
+        <div className="p-3">
+          <InlineCitationSource
+            title={citation.title}
+            url={citation.url}
+            description={citation.snippet}
+          />
+          <a
+            href={citation.url}
+            target="_blank"
+            rel="noopener noreferrer"
+            className="text-primary mt-2 inline-flex items-center gap-1 text-xs hover:underline"
+          >
+            Visit source
+            <ExternalLinkIcon className="size-3" />
+          </a>
+        </div>
+      </InlineCitationCardBody>
+    </InlineCitationCard>
+  );
+}
+
+/**
+ * Citation link component that renders as a hover card badge
+ */
+function CitationLink({
+  citation,
+  href,
+  children,
+}: {
+  citation: Citation;
+  href: string;
+  children: React.ReactNode;
+}) {
+  const domain = extractDomainFromUrl(href);
+
+  return (
+    <InlineCitationCard>
+      <HoverCardTrigger asChild>
+        <a
+          href={href}
+          target="_blank"
+          rel="noopener noreferrer"
+          className="inline-flex items-center"
+          onClick={(e) => e.stopPropagation()}
+        >
+          <Badge
+            variant="secondary"
+            className="mx-0.5 cursor-pointer gap-1 rounded-full px-2 py-0.5 text-xs font-normal hover:bg-secondary/80"
+          >
+            {children ?? domain}
+            <ExternalLinkIcon className="size-3" />
+          </Badge>
+        </a>
+      </HoverCardTrigger>
+      <InlineCitationCardBody>
+        <div className="p-3">
+          <InlineCitationSource
+            title={citation.title}
+            url={href}
+            description={citation.snippet}
+          />
+          <a
+            href={href}
+            target="_blank"
+            rel="noopener noreferrer"
+            className="text-primary mt-2 inline-flex items-center gap-1 text-xs hover:underline"
+          >
+            Visit source
+            <ExternalLinkIcon className="size-3" />
+          </a>
+        </div>
+      </InlineCitationCardBody>
+    </InlineCitationCard>
+  );
+}
 const MessageContent = memo(MessageContent_);

frontend/src/components/workspace/recent-chat-list.tsx

@@ -1,16 +1,27 @@
 "use client";
 
-import { MoreHorizontal, Trash2 } from "lucide-react";
+import { MoreHorizontal, Pencil, Share2, Trash2 } from "lucide-react";
 import Link from "next/link";
 import { useParams, usePathname, useRouter } from "next/navigation";
-import { useCallback } from "react";
+import { useCallback, useState } from "react";
+import { toast } from "sonner";
 
+import { Button } from "@/components/ui/button";
+import {
+  Dialog,
+  DialogContent,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
 import {
   DropdownMenu,
   DropdownMenuContent,
   DropdownMenuItem,
+  DropdownMenuSeparator,
   DropdownMenuTrigger,
 } from "@/components/ui/dropdown-menu";
+import { Input } from "@/components/ui/input";
 import {
   SidebarGroup,
   SidebarGroupContent,
@@ -21,7 +32,11 @@ import {
   SidebarMenuItem,
 } from "@/components/ui/sidebar";
 import { useI18n } from "@/core/i18n/hooks";
-import { useDeleteThread, useThreads } from "@/core/threads/hooks";
+import {
+  useDeleteThread,
+  useRenameThread,
+  useThreads,
+} from "@/core/threads/hooks";
 import { pathOfThread, titleOfThread } from "@/core/threads/utils";
 import { env } from "@/env";
 
@@ -32,6 +47,13 @@ export function RecentChatList() {
   const { thread_id: threadIdFromPath } = useParams<{ thread_id: string }>();
   const { data: threads = [] } = useThreads();
   const { mutate: deleteThread } = useDeleteThread();
+  const { mutate: renameThread } = useRenameThread();
+
+  // Rename dialog state
+  const [renameDialogOpen, setRenameDialogOpen] = useState(false);
+  const [renameThreadId, setRenameThreadId] = useState<string | null>(null);
+  const [renameValue, setRenameValue] = useState("");
+
   const handleDelete = useCallback(
     (threadId: string) => {
       deleteThread({ threadId });
@@ -50,67 +72,155 @@ export function RecentChatList() {
     },
     [deleteThread, router, threadIdFromPath, threads],
   );
+
+  const handleRenameClick = useCallback(
+    (threadId: string, currentTitle: string) => {
+      setRenameThreadId(threadId);
+      setRenameValue(currentTitle);
+      setRenameDialogOpen(true);
+    },
+    [],
+  );
+
+  const handleRenameSubmit = useCallback(() => {
+    if (renameThreadId && renameValue.trim()) {
+      renameThread({ threadId: renameThreadId, title: renameValue.trim() });
+      setRenameDialogOpen(false);
+      setRenameThreadId(null);
+      setRenameValue("");
+    }
+  }, [renameThread, renameThreadId, renameValue]);
+
+  const handleShare = useCallback(
+    async (threadId: string) => {
+      // Always use Vercel URL for sharing so others can access
+      const VERCEL_URL = "https://deer-flow-v2.vercel.app";
+      const isLocalhost =
+        window.location.hostname === "localhost" ||
+        window.location.hostname === "127.0.0.1";
+      // On localhost: use Vercel URL; On production: use current origin
+      const baseUrl = isLocalhost ? VERCEL_URL : window.location.origin;
+      const shareUrl = `${baseUrl}/workspace/chats/${threadId}`;
+      try {
+        await navigator.clipboard.writeText(shareUrl);
+        toast.success(t.clipboard.linkCopied);
+      } catch {
+        toast.error(t.clipboard.failedToCopyToClipboard);
+      }
+    },
+    [t],
+  );
   if (threads.length === 0) {
     return null;
   }
   return (
-    <SidebarGroup>
-      <SidebarGroupLabel>
-        {env.NEXT_PUBLIC_STATIC_WEBSITE_ONLY !== "true"
-          ? t.sidebar.recentChats
-          : t.sidebar.demoChats}
-      </SidebarGroupLabel>
-      <SidebarGroupContent className="group-data-[collapsible=icon]:pointer-events-none group-data-[collapsible=icon]:-mt-8 group-data-[collapsible=icon]:opacity-0">
-        <SidebarMenu>
-          <div className="flex w-full flex-col gap-1">
-            {threads.map((thread) => {
-              const isActive = pathOfThread(thread.thread_id) === pathname;
-              return (
-                <SidebarMenuItem
-                  key={thread.thread_id}
-                  className="group/side-menu-item"
-                >
-                  <SidebarMenuButton isActive={isActive} asChild>
-                    <div>
-                      <Link
-                        className="text-muted-foreground block w-full whitespace-nowrap group-hover/side-menu-item:overflow-hidden"
-                        href={pathOfThread(thread.thread_id)}
-                      >
-                        {titleOfThread(thread)}
-                      </Link>
-                      {env.NEXT_PUBLIC_STATIC_WEBSITE_ONLY !== "true" && (
-                        <DropdownMenu>
-                          <DropdownMenuTrigger asChild>
-                            <SidebarMenuAction
-                              showOnHover
-                              className="bg-background/50 hover:bg-background"
+    <>
+      <SidebarGroup>
+        <SidebarGroupLabel>
+          {env.NEXT_PUBLIC_STATIC_WEBSITE_ONLY !== "true"
+            ? t.sidebar.recentChats
+            : t.sidebar.demoChats}
+        </SidebarGroupLabel>
+        <SidebarGroupContent className="group-data-[collapsible=icon]:pointer-events-none group-data-[collapsible=icon]:-mt-8 group-data-[collapsible=icon]:opacity-0">
+          <SidebarMenu>
+            <div className="flex w-full flex-col gap-1">
+              {threads.map((thread) => {
+                const isActive = pathOfThread(thread.thread_id) === pathname;
+                return (
+                  <SidebarMenuItem
+                    key={thread.thread_id}
+                    className="group/side-menu-item"
+                  >
+                    <SidebarMenuButton isActive={isActive} asChild>
+                      <div>
+                        <Link
+                          className="text-muted-foreground block w-full whitespace-nowrap group-hover/side-menu-item:overflow-hidden"
+                          href={pathOfThread(thread.thread_id)}
+                        >
+                          {titleOfThread(thread)}
+                        </Link>
+                        {env.NEXT_PUBLIC_STATIC_WEBSITE_ONLY !== "true" && (
+                          <DropdownMenu>
+                            <DropdownMenuTrigger asChild>
+                              <SidebarMenuAction
+                                showOnHover
+                                className="bg-background/50 hover:bg-background"
+                              >
+                                <MoreHorizontal />
+                                <span className="sr-only">{t.common.more}</span>
+                              </SidebarMenuAction>
+                            </DropdownMenuTrigger>
+                            <DropdownMenuContent
+                              className="w-48 rounded-lg"
+                              side={"right"}
+                              align={"start"}
                             >
-                              <MoreHorizontal />
-                              <span className="sr-only">{t.common.more}</span>
-                            </SidebarMenuAction>
-                          </DropdownMenuTrigger>
-                          <DropdownMenuContent
-                            className="w-48 rounded-lg"
-                            side={"right"}
-                            align={"start"}
-                          >
-                            <DropdownMenuItem
-                              onSelect={() => handleDelete(thread.thread_id)}
-                            >
-                              <Trash2 className="text-muted-foreground" />
-                              <span>{t.common.delete}</span>
-                            </DropdownMenuItem>
-                          </DropdownMenuContent>
-                        </DropdownMenu>
-                      )}
-                    </div>
-                  </SidebarMenuButton>
-                </SidebarMenuItem>
-              );
-            })}
+                              <DropdownMenuItem
+                                onSelect={() =>
+                                  handleRenameClick(
+                                    thread.thread_id,
+                                    titleOfThread(thread),
+                                  )
+                                }
+                              >
+                                <Pencil className="text-muted-foreground" />
+                                <span>{t.common.rename}</span>
+                              </DropdownMenuItem>
+                              <DropdownMenuItem
+                                onSelect={() => handleShare(thread.thread_id)}
+                              >
+                                <Share2 className="text-muted-foreground" />
+                                <span>{t.common.share}</span>
+                              </DropdownMenuItem>
+                              <DropdownMenuSeparator />
+                              <DropdownMenuItem
+                                onSelect={() => handleDelete(thread.thread_id)}
+                              >
+                                <Trash2 className="text-muted-foreground" />
+                                <span>{t.common.delete}</span>
+                              </DropdownMenuItem>
+                            </DropdownMenuContent>
+                          </DropdownMenu>
+                        )}
+                      </div>
+                    </SidebarMenuButton>
+                  </SidebarMenuItem>
+                );
+              })}
+            </div>
+          </SidebarMenu>
+        </SidebarGroupContent>
+      </SidebarGroup>
+
+      {/* Rename Dialog */}
+      <Dialog open={renameDialogOpen} onOpenChange={setRenameDialogOpen}>
+        <DialogContent className="sm:max-w-[425px]">
+          <DialogHeader>
+            <DialogTitle>{t.common.rename}</DialogTitle>
+          </DialogHeader>
+          <div className="py-4">
+            <Input
+              value={renameValue}
+              onChange={(e) => setRenameValue(e.target.value)}
+              placeholder={t.common.rename}
+              onKeyDown={(e) => {
+                if (e.key === "Enter") {
+                  handleRenameSubmit();
+                }
+              }}
+            />
           </div>
-        </SidebarMenu>
-      </SidebarGroupContent>
-    </SidebarGroup>
+          <DialogFooter>
+            <Button
+              variant="outline"
+              onClick={() => setRenameDialogOpen(false)}
+            >
+              {t.common.cancel}
+            </Button>
+            <Button onClick={handleRenameSubmit}>{t.common.save}</Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+    </>
   );
 }