diff --git a/ex_app/lib/all_tools/external.py b/ex_app/lib/all_tools/external.py
index 30ff70f..2bf65e4 100644
--- a/ex_app/lib/all_tools/external.py
+++ b/ex_app/lib/all_tools/external.py
@@ -1,6 +1,9 @@
 # SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
 # SPDX-License-Identifier: AGPL-3.0-or-later
 import typing
+from typing import Optional
+import datetime
+import urllib.parse
 from time import sleep
 
 import httpx
@@ -55,22 +58,24 @@ def get_current_weather_for_coordinates(lat: str, lon: str) -> dict[str, typing.
 
 	@tool
 	@safe_tool
-	def get_public_transport_route_for_coordinates(origin_lat: str, origin_lon: str, destination_lat: str, destination_lon: str, routes: int) -> dict[str, typing.Any]:
+	def get_public_transport_route_for_coordinates(origin_lat: str, origin_lon: str, destination_lat: str, destination_lon: str, routes: int, departure_time: str | None = None):
 		"""
 		Retrieve a public transport route between two coordinates
-		When using get_public_transport_route_for_coordinates, always let the user know that the routing service here.com was used.
 		:param origin_lat: Latitude of the starting point
 		:param origin_lon: Longitude of the starting point
 		:param destination_lat: Latitude of the destination
 		:param destination_lon: Longitude of the destination
 		:param routes: the number of routes returned
-		:return: 
+		:param departure_time: time of departure, formatted like '2019-06-24T01:23:45'. Optional, leave empty for the next routes from now
+		:return: the routes, times are given in local time according to origin and destination
 		"""
 
+		if departure_time is None:
+			departure_time = urllib.parse.quote_plus(datetime.datetime.now(datetime.UTC).isoformat())
 		api_key = nc.appconfig_ex.get_value('here_api')
 		res = httpx.get('https://transit.hereapi.com/v8/routes?transportMode=car&origin=' 
 			+ origin_lat + ',' + origin_lon + '&destination=' + destination_lat + ',' + destination_lon 
-			+ '&alternatives=' + str(routes-1) + '&apikey=' + api_key)
+			+ '&alternatives=' + str(routes-1) + '&departureTime=' + departure_time + '&apikey=' + api_key)
 		json = res.json()
 		return json