diff --git a/src/renderer/features/details-sidebar/atoms/index.ts b/src/renderer/features/details-sidebar/atoms/index.ts
index 415aa2706..f91986020 100644
--- a/src/renderer/features/details-sidebar/atoms/index.ts
+++ b/src/renderer/features/details-sidebar/atoms/index.ts
@@ -9,6 +9,7 @@ import {
   FileDiff,
   ListTodo,
   GitPullRequest,
+  Activity,
 } from "lucide-react"
 import { OriginalMCPIcon } from "../../../components/ui/icons"
 
@@ -16,7 +17,7 @@ import { OriginalMCPIcon } from "../../../components/ui/icons"
 // Widget System Types & Registry
 // ============================================================================
 
-export type WidgetId = "info" | "todo" | "plan" | "terminal" | "diff" | "mcp" | "pr"
+export type WidgetId = "info" | "tasks" | "todo" | "plan" | "terminal" | "diff" | "mcp" | "pr"
 
 export interface WidgetConfig {
   id: WidgetId
@@ -29,6 +30,7 @@ export interface WidgetConfig {
 export const WIDGET_REGISTRY: WidgetConfig[] = [
   { id: "info", label: "Workspace", icon: Box, canExpand: false, defaultVisible: true },
   { id: "pr", label: "Pull Request", icon: GitPullRequest, canExpand: false, defaultVisible: false },
+  { id: "tasks", label: "Tasks", icon: Activity, canExpand: false, defaultVisible: true },
   { id: "todo", label: "To-dos", icon: ListTodo, canExpand: false, defaultVisible: true },
   { id: "plan", label: "Plan", icon: FileText, canExpand: true, defaultVisible: true },
   { id: "terminal", label: "Terminal", icon: Terminal, canExpand: true, defaultVisible: false },
diff --git a/src/renderer/features/details-sidebar/details-sidebar.tsx b/src/renderer/features/details-sidebar/details-sidebar.tsx
index ecae42d69..8835eecf2 100644
--- a/src/renderer/features/details-sidebar/details-sidebar.tsx
+++ b/src/renderer/features/details-sidebar/details-sidebar.tsx
@@ -2,7 +2,7 @@
 
 import { useCallback, useEffect, useMemo, useRef, useState } from "react"
 import { useAtom, useAtomValue, useSetAtom } from "jotai"
-import { ArrowUpRight, TerminalSquare, Box, ListTodo, GitPullRequest } from "lucide-react"
+import { ArrowUpRight, TerminalSquare, Box, ListTodo, GitPullRequest, Activity } from "lucide-react"
 import { ResizableSidebar } from "@/components/ui/resizable-sidebar"
 import { Button } from "@/components/ui/button"
 import {
@@ -35,6 +35,7 @@ import {
 import { WidgetSettingsPopup } from "./widget-settings-popup"
 import { InfoSection } from "./sections/info-section"
 import { TodoWidget } from "./sections/todo-widget"
+import { TasksWidget } from "./sections/tasks-widget"
 import { PlanWidget } from "./sections/plan-widget"
 import { TerminalWidget } from "./sections/terminal-widget"
 import { ChangesWidget } from "./sections/changes-widget"
@@ -56,6 +57,8 @@ function getWidgetIcon(widgetId: WidgetId) {
   switch (widgetId) {
     case "info":
       return Box
+    case "tasks":
+      return Activity
     case "todo":
       return ListTodo
     case "plan":
@@ -442,6 +445,11 @@ export function DetailsSidebar({
                   </WidgetCard>
                 )
 
+              case "tasks":
+                return (
+                  <TasksWidget key="tasks" subChatId={activeSubChatId || null} />
+                )
+
               case "todo":
                 return (
                   <TodoWidget key="todo" subChatId={activeSubChatId || null} />
diff --git a/src/renderer/features/details-sidebar/sections/tasks-widget.tsx b/src/renderer/features/details-sidebar/sections/tasks-widget.tsx
new file mode 100644
index 000000000..170df242a
--- /dev/null
+++ b/src/renderer/features/details-sidebar/sections/tasks-widget.tsx
@@ -0,0 +1,258 @@
+"use client"
+
+import { memo, useEffect, useMemo, useRef, useState } from "react"
+import { atom, useAtomValue } from "jotai"
+import { atomFamily } from "jotai/utils"
+import { Activity, Loader2 } from "lucide-react"
+import { cn } from "@/lib/utils"
+import {
+  getPerChatMessageKey,
+  messageAtomFamily,
+  messageIdsPerChatAtom,
+  type Message,
+} from "@/features/agents/stores/message-store"
+import { useStreamingStatusStore } from "@/features/agents/stores/streaming-status-store"
+
+interface TasksWidgetProps {
+  subChatId: string | null
+}
+
+interface RunningTask {
+  toolCallId: string
+  toolName: string
+  summary: string
+  startedAt: number
+  parentId: string | null
+  children: RunningTask[]
+}
+
+// Tools that are tracked elsewhere (Todo widget / plan approvals) or are not real work.
+const EXCLUDED_TOOL_NAMES = new Set([
+  "TodoWrite",
+  "TaskCreate",
+  "TaskUpdate",
+  "TaskList",
+  "TaskGet",
+  "TaskOutput",
+  "ExitPlanMode",
+  "Thinking",
+])
+
+function summarizeInput(input: unknown): string {
+  if (!input || typeof input !== "object") return ""
+  const rec = input as Record<string, unknown>
+  const preferredKeys = [
+    "command",
+    "file_path",
+    "path",
+    "pattern",
+    "description",
+    "url",
+    "query",
+    "prompt",
+    "subagent_type",
+  ]
+  for (const key of preferredKeys) {
+    const v = rec[key]
+    if (typeof v === "string" && v.length > 0) return v
+  }
+  for (const key in rec) {
+    const v = rec[key]
+    if (typeof v === "string" && v.length > 0) return v
+  }
+  return ""
+}
+
+function formatElapsed(ms: number): string {
+  const sec = Math.max(0, Math.floor(ms / 1000))
+  if (sec < 60) return `${sec}s`
+  const min = Math.floor(sec / 60)
+  const rem = sec % 60
+  return `${min}m ${rem.toString().padStart(2, "0")}s`
+}
+
+// Derived atom: the last assistant Message for a given subChatId.
+// Scans from the end of messageIdsPerChatAtom; returns null if none found.
+const lastAssistantMessageForSubChatAtomFamily = atomFamily((subChatId: string) =>
+  atom<Message | null>((get) => {
+    const ids = get(messageIdsPerChatAtom(subChatId))
+    for (let i = ids.length - 1; i >= 0; i--) {
+      const id = ids[i]
+      if (!id) continue
+      const msg = get(messageAtomFamily(getPerChatMessageKey(subChatId, id)))
+      if (msg && msg.role === "assistant") return msg
+    }
+    return null
+  }),
+)
+
+export const TasksWidget = memo(function TasksWidget({
+  subChatId,
+}: TasksWidgetProps) {
+  const key = subChatId || "default"
+
+  const isStreaming = useStreamingStatusStore((s) => s.isStreaming(key))
+
+  const lastAssistantAtom = useMemo(
+    () => lastAssistantMessageForSubChatAtomFamily(key),
+    [key],
+  )
+  const lastAssistant = useAtomValue(lastAssistantAtom)
+
+  const startedAtRef = useRef<Map<string, number>>(new Map())
+
+  const tasks = useMemo<RunningTask[]>(() => {
+    if (!isStreaming || !lastAssistant) return []
+
+    const parts = lastAssistant.parts || []
+    const byId = new Map<string, RunningTask>()
+
+    for (const part of parts) {
+      if (!part?.type || typeof part.type !== "string") continue
+      if (!part.type.startsWith("tool-")) continue
+      if (!part.toolCallId) continue
+
+      const st = part.state
+      const isRunning =
+        st !== "output-available" &&
+        st !== "output-error" &&
+        st !== "result" &&
+        st !== "input-error"
+      if (!isRunning) continue
+
+      const toolName = part.type.slice(5)
+      if (EXCLUDED_TOOL_NAMES.has(toolName)) continue
+
+      const colonIdx = part.toolCallId.indexOf(":")
+      const parentId =
+        colonIdx > -1 ? part.toolCallId.slice(0, colonIdx) : null
+
+      // AI SDK exposes transform-provided startedAt on `callProviderMetadata`;
+      // fall back to `providerMetadata` and then to first-sighting time.
+      const metaStart =
+        (part.callProviderMetadata?.custom?.startedAt as number | undefined) ??
+        (part.providerMetadata?.custom?.startedAt as number | undefined) ??
+        (part.startedAt as number | undefined)
+      let startedAt =
+        typeof metaStart === "number"
+          ? metaStart
+          : startedAtRef.current.get(part.toolCallId)
+      if (typeof startedAt !== "number") {
+        startedAt = Date.now()
+      }
+      startedAtRef.current.set(part.toolCallId, startedAt)
+
+      byId.set(part.toolCallId, {
+        toolCallId: part.toolCallId,
+        toolName,
+        summary: summarizeInput(part.input).slice(0, 80),
+        startedAt,
+        parentId,
+        children: [],
+      })
+    }
+
+    const roots: RunningTask[] = []
+    for (const task of byId.values()) {
+      if (task.parentId && byId.has(task.parentId)) {
+        byId.get(task.parentId)!.children.push(task)
+      } else {
+        roots.push(task)
+      }
+    }
+    return roots
+  }, [isStreaming, lastAssistant])
+
+  // Prune startedAt entries that no longer correspond to a running tool.
+  useEffect(() => {
+    if (tasks.length === 0) {
+      startedAtRef.current.clear()
+      return
+    }
+    const live = new Set<string>()
+    const walk = (list: RunningTask[]) => {
+      for (const t of list) {
+        live.add(t.toolCallId)
+        walk(t.children)
+      }
+    }
+    walk(tasks)
+    for (const id of Array.from(startedAtRef.current.keys())) {
+      if (!live.has(id)) startedAtRef.current.delete(id)
+    }
+  }, [tasks])
+
+  // Tick once per second while the list is non-empty to update elapsed times.
+  const [, setTick] = useState(0)
+  useEffect(() => {
+    if (tasks.length === 0) return
+    const h = setInterval(() => setTick((n) => n + 1), 1000)
+    return () => clearInterval(h)
+  }, [tasks.length])
+
+  const total = useMemo(() => {
+    let n = 0
+    const walk = (list: RunningTask[]) => {
+      for (const t of list) {
+        n++
+        walk(t.children)
+      }
+    }
+    walk(tasks)
+    return n
+  }, [tasks])
+
+  if (tasks.length === 0) return null
+
+  return (
+    <div className="mx-2 mb-2">
+      <div className="rounded-t-lg border border-b-0 border-border/50 bg-muted/30 px-2 h-8 flex items-center">
+        <div className="flex items-center gap-2 flex-1 min-w-0">
+          <Activity className="h-3.5 w-3.5 text-muted-foreground flex-shrink-0" />
+          <span className="text-xs font-medium text-foreground">Tasks</span>
+          <span className="text-xs text-muted-foreground flex-1 truncate">
+            Running now
+          </span>
+          <span className="text-xs text-muted-foreground tabular-nums flex-shrink-0">
+            {total}
+          </span>
+        </div>
+      </div>
+      <div className="rounded-b-lg border border-border/50 border-t-0 py-0.5">
+        {tasks.map((task) => (
+          <TaskRow key={task.toolCallId} task={task} depth={0} />
+        ))}
+      </div>
+    </div>
+  )
+})
+
+function TaskRow({ task, depth }: { task: RunningTask; depth: number }) {
+  const elapsed = formatElapsed(Date.now() - task.startedAt)
+  return (
+    <>
+      <div
+        className={cn(
+          "flex items-center gap-2 px-2 py-1.5 text-xs",
+          depth > 0 && "pl-6 ml-3 border-l border-border/30",
+        )}
+      >
+        <Loader2 className="h-3 w-3 animate-spin text-muted-foreground flex-shrink-0" />
+        <span className="text-foreground font-medium flex-shrink-0">
+          {task.toolName}
+        </span>
+        {task.summary ? (
+          <span className="text-muted-foreground truncate min-w-0">
+            {task.summary}
+          </span>
+        ) : null}
+        <span className="ml-auto text-muted-foreground tabular-nums flex-shrink-0">
+          {elapsed}
+        </span>
+      </div>
+      {task.children.map((child) => (
+        <TaskRow key={child.toolCallId} task={child} depth={depth + 1} />
+      ))}
+    </>
+  )
+}