feat: session busy indicator — daemon tracks mid-turn state (agent_start/settled), busy field on session rows + live broadcast; pulsing pip in sidebar and cards (265 web tests, daemon 95.4%)

daemon/hub.go

@@ -100,6 +100,7 @@ type SessionView struct {
 	Repo        *string `json:"repo"`
 	StartedAt   int64   `json:"startedAt"`
 	Online      bool    `json:"online"`
+	Busy        bool    `json:"busy"`
 	LastEventAt int64   `json:"lastEventAt"`
 }
 
@@ -342,6 +343,10 @@ type Hub struct {
 	agents map[string]*agentConn
 	webs   map[*webClient]struct{}
 
+	// busy tracks sessions mid-turn (agent_start without agent_settled),
+	// surfaced on session rows so the UI can show a live activity pulse.
+	busy map[string]bool
+
 	// SpawnStatus lets the API push spawn job snapshots to web clients.
 	SpawnStatus func() []SpawnJob
 
@@ -353,6 +358,7 @@ func NewHub(store *Store) *Hub {
 		store:  store,
 		agents: make(map[string]*agentConn),
 		webs:   make(map[*webClient]struct{}),
+		busy:   make(map[string]bool),
 		upgrader: websocket.Upgrader{
 			ReadBufferSize:  4096,
 			WriteBufferSize: 4096,
@@ -392,6 +398,7 @@ func (h *Hub) SessionsView() []SessionView {
 			LastEventAt: row.LastEventAt,
 		}
 		_, v.Online = h.agents[row.ID]
+		v.Busy = h.busy[row.ID]
 		out = append(out, v)
 	}
 	return out
@@ -607,6 +614,18 @@ func (h *Hub) handleEvent(f frame) {
 			log.Printf("hub: touch session %s: %v", f.sessionID, err)
 		}
 	}
+	// Track mid-turn state for the session-list activity pulse.
+	if f.typ == evAgentStart || f.typ == evAgentSettled {
+		busy := f.typ == evAgentStart
+		h.mu.Lock()
+		if h.busy[f.sessionID] != busy {
+			h.busy[f.sessionID] = busy
+			h.mu.Unlock()
+			go h.BroadcastSessionList()
+		} else {
+			h.mu.Unlock()
+		}
+	}
 	h.publishEvent(f.sessionID, f.seq, json.RawMessage(f.raw))
 }
 
@@ -624,6 +643,9 @@ func (h *Hub) unregister(ac *agentConn) {
 		if err := h.store.SetOnline(ac.sessionID, false); err != nil {
 			log.Printf("hub: mark offline %s: %v", ac.sessionID, err)
 		}
+		h.mu.Lock()
+		delete(h.busy, ac.sessionID)
+		h.mu.Unlock()
 	}
 	h.BroadcastSessionList()
 }

daemon/hub_extra_test.go

@@ -714,3 +714,34 @@ func TestWebResubscribeSplitsEventBatches(t *testing.T) {
 	_ = agent2.WriteJSON(map[string]any{"v": 1, "type": evMessageUpdate, "sessionId": "s2", "seq": 1, "ts": 11, "delta": "two"})
 	readBatch("s2") // event B must arrive as its own frame, never mixed with A's
 }
+
+func TestHubBusyFlagLifecycle(t *testing.T) {
+	ts, _, hub := newTestServerHub(t)
+	ws := dialAgent(t, ts)
+	defer ws.Close()
+	_ = ws.WriteJSON(helloFrame("busy-1"))
+	_ = readFrame(t, ws)
+	sendEv := func(typ string, seq int64) {
+		_ = ws.WriteJSON(map[string]any{
+			"v": 1, "sessionId": "busy-1", "seq": seq, "ts": 1, "type": typ,
+		})
+	}
+	sendEv("agent_start", 1)
+	waitFor(t, 3*time.Second, func() bool {
+		for _, s := range hub.SessionsView() {
+			if s.ID == "busy-1" {
+				return s.Busy
+			}
+		}
+		return false
+	})
+	sendEv("agent_settled", 2)
+	waitFor(t, 3*time.Second, func() bool {
+		for _, s := range hub.SessionsView() {
+			if s.ID == "busy-1" {
+				return !s.Busy
+			}
+		}
+		return false
+	})
+}

web/src/App.test.tsx

@@ -29,6 +29,7 @@ const sessions: SessionListItem[] = [
 		repo: "g/a",
 		startedAt: 10,
 		online: true,
+				busy: false,
 		lastEventAt: null,
 	},
 	{
@@ -41,6 +42,7 @@ const sessions: SessionListItem[] = [
 		repo: "g/b",
 		startedAt: 20,
 		online: true,
+				busy: false,
 		lastEventAt: null,
 	},
 	// bare session: exercises null-name/null-repo fallbacks
@@ -54,10 +56,23 @@ const sessions: SessionListItem[] = [
 		repo: null,
 		startedAt: 30,
 		online: true,
+				busy: false,
 		lastEventAt: null,
 	},
 ];
 
+function seedApiWith(list: unknown): void {
+	mockFetchJson((url) => {
+		if (url.endsWith("/stats"))
+			return { turns: 0, inputTokens: 0, outputTokens: 0, totalCost: 0, sessionsCount: 0, onlineCount: 0 };
+		if (url.includes("/api/sessions"))
+			return url.includes("/events") ? [] : list;
+		if (url.includes("/api/gitlab/status"))
+			return { connected: false, baseUrl: "https://gl" };
+		return [];
+	});
+}
+
 function seedApi(): void {
 	mockFetchJson((url) => {
 		if (url.endsWith("/stats"))
@@ -290,3 +305,21 @@ describe("conn banner + sidebar sections", () => {
 		expect(screen.queryByText(/reconnecting/i)).toBeNull();
 	});
 });
+
+describe("busy pip", () => {
+	it("sidebar shows activity pip only for online+busy sessions", async () => {
+		seedApiWith([
+			{ id: "b1", name: "working", online: true, busy: true, startedAt: 1, lastEventAt: 2 },
+			{ id: "b2", name: "idle", online: true, busy: false, startedAt: 1, lastEventAt: 2 },
+			{ id: "b3", name: "offlinebusy", online: false, busy: true, startedAt: 1, lastEventAt: 2 },
+		]);
+		seedSettings();
+		renderApp("/");
+		await waitFor(() => expect(FakeWebSocket.instances.length).toBe(1));
+		act(() => FakeWebSocket.last().serverOpen());
+		const sidebar = screen.getByLabelText("Sessions");
+		const pips = sidebar.querySelectorAll(".busy-pip");
+		expect(pips).toHaveLength(1);
+		expect(pips[0]?.closest("a")?.getAttribute("href")).toBe("/s/b1");
+	});
+});

web/src/App.tsx

@@ -78,6 +78,9 @@ function SidebarSection({
 						style={{ display: "inline-block" }}
 					/>
 					<span className="link-label">{s.name ?? s.repo ?? s.id}</span>
+					{s.online && s.busy && (
+						<span className="busy-pip" aria-label="agent working" title="agent working" />
+					)}
 				</NavLink>
 			))}
 		</>

web/src/ChatView.test.tsx

@@ -33,6 +33,7 @@ const sessions: SessionListItem[] = [
 		repo: null,
 		startedAt: 0,
 		online: true,
+				busy: false,
 		lastEventAt: 1,
 	},
 ];

web/src/SessionsView.test.tsx

@@ -22,6 +22,7 @@ function session(p: Partial<SessionListItem>): SessionListItem {
 		repo: null,
 		startedAt: 100,
 		online: true,
+				busy: false,
 		lastEventAt: null,
 		...p,
 	};
@@ -107,6 +108,7 @@ describe("SessionsView", () => {
 					cwd: "/fallback",
 					startedAt: 100,
 					online: true,
+				busy: false,
 				}),
 			],
 		});
@@ -496,3 +498,17 @@ describe("SessionsView delete session", () => {
 		expect(screen.getByLabelText("Delete session dead")).toBeInTheDocument();
 	});
 });
+
+describe("busy indicator on cards", () => {
+	it("card shows pip when online+busy, none otherwise", () => {
+		renderView({
+			sessions: [
+				session({ id: "w", name: "working", busy: true }),
+				session({ id: "i", name: "idle", busy: false }),
+				session({ id: "o", name: "off", busy: true, online: false }),
+			],
+		});
+		const pips = document.querySelectorAll(".busy-pip");
+		expect(pips).toHaveLength(1);
+	});
+});

web/src/SessionsView.tsx

@@ -44,6 +44,13 @@ function SessionCard({
 			<span className="card-body">
 			<span className="card-title" style={{ display: "block" }}>
 				{s.name ?? s.repo ?? s.cwd}
+				{s.online && s.busy && (
+					<span
+						className="busy-pip"
+						aria-label="agent working"
+						title="agent working"
+					/>
+				)}
 			</span>
 				<span className="card-meta" style={{ display: "flex" }}>
 					{s.repo !== null && <span>{s.repo}</span>}

web/src/SpawnView.test.tsx

@@ -264,6 +264,7 @@ describe("SpawnView spawn+poll", () => {
 								repo: "g/proj",
 								startedAt: 1,
 								online: true,
+				busy: false,
 								lastEventAt: 1,
 							},
 						]

web/src/index.css

@@ -1429,3 +1429,20 @@ mark.hit {
 		padding: 11px 13px;
 	}
 }
+
+/* ---------- busy activity pip ---------- */
+
+.busy-pip {
+  display: inline-block;
+  width: 8px;
+  height: 8px;
+  margin-left: 7px;
+  border-radius: 50%;
+  background: var(--accent);
+  animation: busy-pulse 1.1s ease-in-out infinite;
+  vertical-align: middle;
+}
+@keyframes busy-pulse {
+  0%, 100% { transform: scale(0.55); opacity: 0.45; box-shadow: 0 0 0 0 rgba(108, 140, 255, 0.5); }
+  50% { transform: scale(1); opacity: 1; box-shadow: 0 0 0 5px rgba(108, 140, 255, 0); }
+}

web/src/protocol.ts

@@ -64,6 +64,7 @@ export interface SessionInfo {
 /** Session list row (REST `GET /api/sessions` + WS `session_list`). */
 export interface SessionListItem extends SessionInfo {
 	online: boolean;
+	busy: boolean;
 	lastEventAt: number | null;
 }
 

web/src/store.test.tsx

@@ -117,6 +117,7 @@ describe("useSessions", () => {
 				id: "s1",
 				name: "one",
 				online: true,
+				busy: false,
 			},
 		] as SessionListItem[];
 		const fetchMock = mockFetchJson((url) => {
@@ -417,6 +418,7 @@ describe("useSessions", () => {
 				id: "s9",
 				name: "x",
 				online: true,
+				busy: false,
 			} as SessionListItem,
 		];
 		await act(async () => {