diff --git a/lib/controllers/app_ctrl.dart b/lib/controllers/app_ctrl.dart
index 9bf9b8d..73e0f23 100644
--- a/lib/controllers/app_ctrl.dart
+++ b/lib/controllers/app_ctrl.dart
@@ -6,8 +6,7 @@ import 'package:livekit_client/livekit_client.dart' as sdk;
 import 'package:livekit_components/livekit_components.dart' as components;
 import 'package:logging/logging.dart';
 import 'package:uuid/uuid.dart';
-
-import '../services/token_service.dart';
+import 'package:flutter_dotenv/flutter_dotenv.dart';
 
 enum AppScreenState { welcome, agent }
 
@@ -30,10 +29,33 @@ class AppCtrl extends ChangeNotifier {
 
   late final sdk.Room room = sdk.Room(roomOptions: const sdk.RoomOptions(enableVisualizer: true));
   late final roomContext = components.RoomContext(room: room);
-  late final sdk.Session session = sdk.Session.fromConfigurableTokenSource(
-    TokenServiceTokenSource(TokenService()),
-    options: sdk.SessionOptions(room: room),
-  );
+  late final sdk.Session session = _createSession(room: room);
+
+  static sdk.Session _createSession({required sdk.Room room}) {
+    // Development-only hardcoded credentials (optional).
+    const hardcodedServerUrl = null; // e.g. 'wss://your-host'
+    const hardcodedToken = null; // e.g. 'eyJ...'
+
+    if (hardcodedServerUrl != null && hardcodedToken != null) {
+      return sdk.Session.fromFixedTokenSource(
+        sdk.LiteralTokenSource(
+          serverUrl: hardcodedServerUrl,
+          participantToken: hardcodedToken,
+        ),
+        options: sdk.SessionOptions(room: room),
+      );
+    }
+
+    final sandboxId = dotenv.env['LIVEKIT_SANDBOX_ID']?.replaceAll('"', '');
+    if (sandboxId == null || sandboxId.isEmpty) {
+      throw StateError('LIVEKIT_SANDBOX_ID is not set and no hardcoded token is configured.');
+    }
+
+    return sdk.Session.fromConfigurableTokenSource(
+      sdk.SandboxTokenSource(sandboxId: sandboxId).cached(),
+      options: sdk.SessionOptions(room: room),
+    );
+  }
 
   bool isSendButtonEnabled = false;
   bool isSessionStarting = false;
diff --git a/lib/services/token_service.dart b/lib/services/token_service.dart
deleted file mode 100644
index 1ea906c..0000000
--- a/lib/services/token_service.dart
+++ /dev/null
@@ -1,128 +0,0 @@
-import 'dart:math';
-
-import 'package:flutter_dotenv/flutter_dotenv.dart';
-import 'package:livekit_client/livekit_client.dart' as sdk;
-
-/// Data class representing the connection details needed to join a LiveKit room
-/// This includes the server URL, room name, participant info, and auth token
-class ConnectionDetails {
-  final String serverUrl;
-  final String roomName;
-  final String participantName;
-  final String participantToken;
-
-  ConnectionDetails({
-    required this.serverUrl,
-    required this.roomName,
-    required this.participantName,
-    required this.participantToken,
-  });
-
-  factory ConnectionDetails.fromJson(Map<String, dynamic> json) {
-    return ConnectionDetails(
-      serverUrl: json['serverUrl'],
-      roomName: json['roomName'],
-      participantName: json['participantName'],
-      participantToken: json['participantToken'],
-    );
-  }
-}
-
-/// An example service for fetching LiveKit authentication tokens
-///
-/// To use the LiveKit Cloud sandbox (development only)
-/// - Enable your sandbox here https://cloud.livekit.io/projects/p_/sandbox/templates/token-server
-/// - Create .env file with your LIVEKIT_SANDBOX_ID
-///
-/// To use a hardcoded token (development only)
-/// - Generate a token: https://docs.livekit.io/home/cli/cli-setup/#generate-access-token
-/// - Set `hardcodedServerUrl` and `hardcodedToken` below
-///
-/// To use your own server (production applications)
-/// - Add a token endpoint to your server with a LiveKit Server SDK https://docs.livekit.io/home/server/generating-tokens/
-/// - Modify or replace this class as needed to connect to your new token server
-/// - Rejoice in your new production-ready LiveKit application!
-///
-/// See https://docs.livekit.io/home/get-started/authentication for more information
-class TokenService {
-  // For hardcoded token usage (development only)
-  final String? hardcodedServerUrl = null;
-  final String? hardcodedToken = null;
-
-  // Get the sandbox ID from environment variables
-  String? get sandboxId {
-    final value = dotenv.env['LIVEKIT_SANDBOX_ID'];
-    if (value != null) {
-      // Remove unwanted double quotes if present
-      return value.replaceAll('"', '');
-    }
-    return null;
-  }
-
-  ConnectionDetails? fetchHardcodedConnectionDetails({
-    required String roomName,
-    required String participantName,
-  }) {
-    if (hardcodedServerUrl == null || hardcodedToken == null) {
-      return null;
-    }
-
-    return ConnectionDetails(
-      serverUrl: hardcodedServerUrl!,
-      roomName: roomName,
-      participantName: participantName,
-      participantToken: hardcodedToken!,
-    );
-  }
-}
-
-/// Bridges [TokenService] to the LiveKit Session API by implementing [TokenSourceConfigurable].
-class TokenServiceTokenSource implements sdk.TokenSourceConfigurable {
-  TokenServiceTokenSource(this._service);
-
-  final TokenService _service;
-  final Random _random = Random();
-
-  @override
-  Future<sdk.TokenSourceResponse> fetch(sdk.TokenRequestOptions options) async {
-    final roomName = options.roomName ?? _randomRoomName();
-    final participantName = options.participantName ?? _randomParticipantName();
-
-    // If hardcoded creds are provided (development only), return them as-is.
-    final hardcoded = _service.fetchHardcodedConnectionDetails(
-      roomName: roomName,
-      participantName: participantName,
-    );
-    if (hardcoded != null) {
-      return sdk.TokenSourceResponse(
-        serverUrl: hardcoded.serverUrl,
-        participantToken: hardcoded.participantToken,
-        participantName: hardcoded.participantName,
-        roomName: hardcoded.roomName,
-      );
-    }
-
-    final sandboxId = _service.sandboxId;
-    if (sandboxId == null) {
-      throw Exception('Sandbox ID is not set and no hardcoded token is configured.');
-    }
-
-    final resolvedOptions = sdk.TokenRequestOptions(
-      roomName: roomName,
-      participantName: participantName,
-      participantIdentity: options.participantIdentity,
-      participantMetadata: options.participantMetadata,
-      participantAttributes: options.participantAttributes,
-      agentName: options.agentName,
-      agentMetadata: options.agentMetadata,
-    );
-
-    // Use the SDK’s sandbox token source so agent dispatch options (agent name/metadata)
-    // are forwarded correctly to the token server.
-    final source = sdk.SandboxTokenSource(sandboxId: sandboxId);
-    return await source.fetch(resolvedOptions);
-  }
-
-  String _randomRoomName() => 'room-${1000 + _random.nextInt(9000)}';
-  String _randomParticipantName() => 'user-${1000 + _random.nextInt(9000)}';
-}
diff --git a/test/widget_test.dart b/test/widget_test.dart
index f38b549..8667719 100644
--- a/test/widget_test.dart
+++ b/test/widget_test.dart
@@ -6,11 +6,20 @@
 // tree, read text, and verify that the values of widget properties are correct.
 
 import 'package:flutter/material.dart';
+import 'package:flutter_dotenv/flutter_dotenv.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:voice_assistant/app.dart';
 
 void main() {
   testWidgets('App builds successfully', (WidgetTester tester) async {
+    await dotenv.load(
+      fileName: '.env',
+      isOptional: true,
+      mergeWith: const {
+        'LIVEKIT_SANDBOX_ID': 'test',
+      },
+    );
+
     // Build our app and trigger a frame.
     await tester.pumpWidget(const VoiceAssistantApp());
     // Dispose resources started by the global controller to avoid pending timers.