fix(mcp): restore lightweight device presence heartbeat

apps/api/MCP_TOOLS.md

@@ -14,7 +14,7 @@ API key passed via `X-API-Key` header. Key encodes:
 Device commands can target **any device in the organization**:
 - If `deviceId` not specified, defaults to `defaultDeviceId` from API key
 - Any org member can run commands on any org device (permissions can be added later)
-- Device must be online (heartbeat within last 60s) to receive commands
+- Device must be online (seen within last 10 minutes) to receive commands
 
 ## Tool Categories
 

apps/desktop/src/renderer/routes/_authenticated/components/AgentHooks/hooks/useDevicePresence/useDevicePresence.ts

@@ -1,33 +1,39 @@
-import { useEffect, useRef } from "react";
+import { useEffect } from "react";
 import { apiTrpcClient } from "renderer/lib/api-trpc-client";
 import { authClient } from "renderer/lib/auth-client";
 import { electronTrpc } from "renderer/lib/electron-trpc";
 
+const PRESENCE_INTERVAL_MS = 5 * 60 * 1000; // 5 minutes
+
 /**
- * Registers this device once on startup so MCP can verify ownership.
- * No polling — just a single upsert into device_presence.
+ * Keeps this device visible to MCP by periodically refreshing
+ * its presence. Registers immediately on startup, then re-registers
+ * every 5 minutes so `list_devices` continues to report the device
+ * as online.
  */
 export function useDevicePresence() {
 	const { data: session } = authClient.useSession();
 	const { data: deviceInfo } = electronTrpc.auth.getDeviceInfo.useQuery();
-	const registeredScopeRef = useRef<string | null>(null);
 
 	useEffect(() => {
 		const orgId = session?.session?.activeOrganizationId;
 		if (!deviceInfo || !orgId) return;
-		if (registeredScopeRef.current === orgId) return;
-		registeredScopeRef.current = orgId;
 
-		apiTrpcClient.device.registerDevice
-			.mutate({
-				deviceId: deviceInfo.deviceId,
-				deviceName: deviceInfo.deviceName,
-				deviceType: "desktop",
-			})
-			.catch(() => {
-				// Registration can fail when offline — will retry on next app launch
-				registeredScopeRef.current = null;
-			});
+		const register = () => {
+			apiTrpcClient.device.registerDevice
+				.mutate({
+					deviceId: deviceInfo.deviceId,
+					deviceName: deviceInfo.deviceName,
+					deviceType: "desktop",
+				})
+				.catch((err) => {
+					console.debug("[device-presence] Registration failed:", err);
+				});
+		};
+
+		register();
+		const interval = setInterval(register, PRESENCE_INTERVAL_MS);
+		return () => clearInterval(interval);
 	}, [deviceInfo, session?.session?.activeOrganizationId]);
 
 	return {

packages/mcp/src/tools/devices/list-devices/list-devices.test.ts

@@ -17,7 +17,7 @@ let fetchedDevices = [
 		deviceId: "device-offline",
 		deviceName: "Grace's iPhone",
 		deviceType: "mobile",
-		lastSeenAt: new Date(Date.now() - 120_000),
+		lastSeenAt: new Date(Date.now() - 15 * 60 * 1000),
 		ownerId: "user-2",
 		ownerName: "Grace",
 		ownerEmail: "grace@example.com",
@@ -114,7 +114,7 @@ describe("list_devices MCP tool", () => {
 				deviceId: "device-offline",
 				deviceName: "Grace's iPhone",
 				deviceType: "mobile",
-				lastSeenAt: new Date(Date.now() - 120_000),
+				lastSeenAt: new Date(Date.now() - 15 * 60 * 1000),
 				ownerId: "user-2",
 				ownerName: "Grace",
 				ownerEmail: "grace@example.com",

packages/mcp/src/tools/devices/list-devices/list-devices.ts

@@ -5,14 +5,14 @@ import { desc, eq } from "drizzle-orm";
 import { z } from "zod";
 import { getMcpContext } from "../../utils";
 
-const DEVICE_ONLINE_WINDOW_MS = 60_000;
+const DEVICE_ONLINE_WINDOW_MS = 10 * 60 * 1000; // 10 minutes
 
 export function register(server: McpServer) {
 	server.registerTool(
 		"list_devices",
 		{
 			description:
-				"List devices in the organization. By default, only devices seen within the last 60 seconds are returned.",
+				"List devices in the organization. By default, only devices seen within the last 10 minutes are returned.",
 			inputSchema: {
 				includeOffline: z
 					.boolean()