diff --git a/src/app/api/tasks/route.ts b/src/app/api/tasks/route.ts
index c1a6c05..5c29c8a 100644
--- a/src/app/api/tasks/route.ts
+++ b/src/app/api/tasks/route.ts
@@ -63,8 +63,8 @@ const TASK_PRIORITIES: Task["priority"][] = ["low", "medium", "high", "urgent"];
 const SPRINT_STATUSES: Sprint["status"][] = ["planning", "active", "completed"];
 const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
 
-// Optimized field selection - fetch all fields needed for board and detail display
-const TASK_FIELDS = [
+// Field sets are split so board loads can avoid heavy attachment payloads.
+const TASK_BASE_FIELDS = [
   "id",
   "title",
   "type",
@@ -80,10 +80,11 @@ const TASK_FIELDS = [
   "due_date",
   "tags",
   "comments",
-  "attachments",
   "description",
 ];
 
+const TASK_DETAIL_ONLY_FIELDS = ["attachments"];
+
 class HttpError extends Error {
   readonly status: number;
   readonly details?: Record<string, unknown>;
@@ -271,7 +272,7 @@ function mapTaskRow(row: Record<string, unknown>, usersById: Map<string, UserPro
 
 // GET - fetch all tasks, projects, and sprints
 // Uses lightweight fields for faster initial load
-export async function GET() {
+export async function GET(request: Request) {
   try {
     const user = await getAuthenticatedUser();
     if (!user) {
@@ -279,7 +280,11 @@ export async function GET() {
     }
     
     const supabase = getServiceSupabase();
-    
+    const includeFullTaskData = new URL(request.url).searchParams.get("include") === "detail";
+    const taskFieldSet = includeFullTaskData
+      ? [...TASK_BASE_FIELDS, ...TASK_DETAIL_ONLY_FIELDS]
+      : TASK_BASE_FIELDS;
+
     // Use Promise.all for parallel queries with optimized field selection
     const [
       { data: projects, error: projectsError },
@@ -289,7 +294,7 @@ export async function GET() {
     ] = await Promise.all([
       supabase.from("projects").select("id, name, description, color, created_at").order("created_at", { ascending: true }),
       supabase.from("sprints").select("id, name, goal, start_date, end_date, status, project_id, created_at").order("start_date", { ascending: true }),
-      supabase.from("tasks").select(TASK_FIELDS.join(", ")).order("updated_at", { ascending: false }),
+      supabase.from("tasks").select(taskFieldSet.join(", ")).order("updated_at", { ascending: false }),
       supabase.from("users").select("id, name, email, avatar_url"),
     ]);
 
@@ -307,7 +312,7 @@ export async function GET() {
     return NextResponse.json({
       projects: (projects || []).map((row) => mapProjectRow(row as Record<string, unknown>)),
       sprints: (sprints || []).map((row) => mapSprintRow(row as Record<string, unknown>)),
-      tasks: ((taskRows as unknown as Record<string, unknown>[] | null) || []).map((row) => mapTaskRow(row, usersById, false)),
+      tasks: ((taskRows as unknown as Record<string, unknown>[] | null) || []).map((row) => mapTaskRow(row, usersById, includeFullTaskData)),
       currentUser: {
         id: user.id,
         name: user.name,
diff --git a/src/app/tasks/[taskId]/page.tsx b/src/app/tasks/[taskId]/page.tsx
index 4376d40..8e5550c 100644
--- a/src/app/tasks/[taskId]/page.tsx
+++ b/src/app/tasks/[taskId]/page.tsx
@@ -256,7 +256,7 @@ export default function TaskDetailPage() {
 
   useEffect(() => {
     if (!authReady) return
-    syncFromServer()
+    syncFromServer({ includeFullTaskData: true })
   }, [authReady, syncFromServer])
 
   useEffect(() => {
@@ -393,7 +393,7 @@ export default function TaskDetailPage() {
     }
   }
 
-  const handleAddComment = () => {
+  const handleAddComment = async () => {
     if (!editedTask || !newComment.trim()) return
 
     const commentAuthorId = getCurrentUserCommentAuthorId(currentUser)
@@ -401,14 +401,28 @@ export default function TaskDetailPage() {
       toast.error("You must be signed in to add a comment.")
       return
     }
-    setEditedTask({
+
+    const nextTask: Task = {
       ...editedTask,
       comments: [...getComments(editedTask.comments), buildComment(newComment.trim(), commentAuthorId)],
-    })
+    }
+
+    setEditedTask(nextTask)
     setNewComment("")
+
+    const success = await updateTask(nextTask.id, {
+      ...nextTask,
+      comments: getComments(nextTask.comments),
+    })
+    if (!success) {
+      toast.error("Failed to save comment", {
+        description: "Comment was added locally but could not sync to the server.",
+        duration: 5000,
+      })
+    }
   }
 
-  const handleAddReply = (parentId: string) => {
+  const handleAddReply = async (parentId: string) => {
     if (!editedTask) return
     const text = replyDrafts[parentId]?.trim()
     if (!text) return
@@ -418,13 +432,26 @@ export default function TaskDetailPage() {
       toast.error("You must be signed in to reply.")
       return
     }
-    setEditedTask({
+    const nextTask: Task = {
       ...editedTask,
       comments: addReplyToThread(getComments(editedTask.comments), parentId, buildComment(text, commentAuthorId)),
-    })
+    }
+
+    setEditedTask(nextTask)
 
     setReplyDrafts((prev) => ({ ...prev, [parentId]: "" }))
     setOpenReplyEditors((prev) => ({ ...prev, [parentId]: false }))
+
+    const success = await updateTask(nextTask.id, {
+      ...nextTask,
+      comments: getComments(nextTask.comments),
+    })
+    if (!success) {
+      toast.error("Failed to save reply", {
+        description: "Reply was added locally but could not sync to the server.",
+        duration: 5000,
+      })
+    }
   }
 
   const handleDeleteComment = (commentId: string) => {
diff --git a/src/lib/server/auth.ts b/src/lib/server/auth.ts
index eb9fc45..2d73246 100644
--- a/src/lib/server/auth.ts
+++ b/src/lib/server/auth.ts
@@ -392,8 +392,6 @@ export async function revokeSession(token: string): Promise<void> {
 }
 
 export async function getUserBySessionToken(token: string): Promise<AuthUser | null> {
-  await deleteExpiredSessions();
-
   const supabase = getServiceSupabase();
   const tokenHash = hashSessionToken(token);
   const now = new Date().toISOString();
diff --git a/src/stores/useTaskStore.ts b/src/stores/useTaskStore.ts
index b87d5a4..b2d6d2e 100644
--- a/src/stores/useTaskStore.ts
+++ b/src/stores/useTaskStore.ts
@@ -90,7 +90,7 @@ interface TaskStore {
   syncError: string | null
 
   // Sync actions
-  syncFromServer: () => Promise<void>
+  syncFromServer: (options?: { includeFullTaskData?: boolean }) => Promise<void>
   setCurrentUser: (user: Partial<UserProfile>) => void
 
   // Project actions
@@ -326,11 +326,12 @@ export const useTaskStore = create<TaskStore>()(
       lastSynced: null,
       syncError: null,
 
-      syncFromServer: async () => {
+      syncFromServer: async (options) => {
         console.log('>>> syncFromServer START')
         set({ isLoading: true, syncError: null })
         try {
-          const res = await fetch('/api/tasks', { cache: 'no-store' })
+          const query = options?.includeFullTaskData ? '?include=detail' : ''
+          const res = await fetch(`/api/tasks${query}`, { cache: 'no-store' })
           console.log('>>> syncFromServer: API response status:', res.status)
           if (!res.ok) {
             const errorPayload = await res.json().catch(() => ({}))