diff --git a/.coverage b/.coverage
index 87c081b..4b5b5d9 100644
Binary files a/.coverage and b/.coverage differ
diff --git a/duty_teller/api/app.py b/duty_teller/api/app.py
index 6c0a13a..1730b20 100644
--- a/duty_teller/api/app.py
+++ b/duty_teller/api/app.py
@@ -3,8 +3,6 @@
 import logging
 import re
 from datetime import date, timedelta
-from typing import Literal
-
 import duty_teller.config as config
 from fastapi import Depends, FastAPI, Request
 from fastapi.middleware.cors import CORSMiddleware
@@ -100,20 +98,16 @@ def list_calendar_events(
     "/api/calendar/ical/{token}.ics",
     summary="Personal calendar ICS",
     description=(
-        "Returns an ICS calendar with the subscribing user's events. "
-        "By default only duty shifts are included; use query parameter events=all "
-        "for all event types (duty, unavailable, vacation). "
+        "Returns an ICS calendar with the subscribing user's duty shifts only. "
         "No Telegram auth; access is by secret token in the URL."
     ),
 )
 def get_personal_calendar_ical(
     token: str,
-    events: Literal["duty", "all"] = "duty",
     session: Session = Depends(get_db_session),
 ) -> Response:
     """
-    Return ICS calendar with the subscribing user's events.
-    Default: only duty shifts. Use ?events=all for duty, unavailable, vacation.
+    Return ICS calendar with the subscribing user's duty shifts only.
     No Telegram auth; access is by secret token in the URL.
     """
     if not _is_valid_calendar_token(token):
@@ -124,9 +118,8 @@ def get_personal_calendar_ical(
     today = date.today()
     from_date = (today - timedelta(days=365)).strftime("%Y-%m-%d")
     to_date = (today + timedelta(days=365 * 2)).strftime("%Y-%m-%d")
-    event_types = ["duty"] if events == "duty" else None
     duties_with_name = get_duties_for_user(
-        session, user.id, from_date=from_date, to_date=to_date, event_types=event_types
+        session, user.id, from_date=from_date, to_date=to_date, event_types=["duty"]
     )
     ics_bytes = build_personal_ics(duties_with_name)
     return Response(
diff --git a/tests/test_app.py b/tests/test_app.py
index 935562d..86400f4 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -336,10 +336,10 @@ def test_calendar_ical_200_returns_only_that_users_duties(
 @patch("duty_teller.api.app.build_personal_ics")
 @patch("duty_teller.api.app.get_duties_for_user")
 @patch("duty_teller.api.app.get_user_by_calendar_token")
-def test_calendar_ical_events_all_returns_all_event_types(
+def test_calendar_ical_ignores_unknown_query_params(
     mock_get_user, mock_get_duties, mock_build_ics, client
 ):
-    """GET /api/calendar/ical/{token}.ics?events=all returns ICS with duty, unavailable, vacation."""
+    """Unknown query params (e.g. events=all) are ignored; response is duty-only."""
     from types import SimpleNamespace
 
     mock_user = SimpleNamespace(id=1, full_name="User A")
@@ -351,39 +351,15 @@ def test_calendar_ical_events_all_returns_all_event_types(
         end_at="2026-06-15T18:00:00Z",
         event_type="duty",
     )
-    unavailable = SimpleNamespace(
-        id=11,
-        user_id=1,
-        start_at="2026-06-16T09:00:00Z",
-        end_at="2026-06-16T18:00:00Z",
-        event_type="unavailable",
-    )
-    vacation = SimpleNamespace(
-        id=12,
-        user_id=1,
-        start_at="2026-06-17T09:00:00Z",
-        end_at="2026-06-17T18:00:00Z",
-        event_type="vacation",
-    )
-    mock_get_duties.return_value = [
-        (duty, "User A"),
-        (unavailable, "User A"),
-        (vacation, "User A"),
-    ]
-    mock_build_ics.return_value = b"BEGIN:VCALENDAR\r\nVEVENT\r\nEND:VCALENDAR"
-    token = "y" * 43
+    mock_get_duties.return_value = [(duty, "User A")]
+    mock_build_ics.return_value = b"BEGIN:VCALENDAR\r\nEND:VCALENDAR"
+    token = "z" * 43
 
     r = client.get(f"/api/calendar/ical/{token}.ics", params={"events": "all"})
     assert r.status_code == 200
-    assert r.headers.get("content-type", "").startswith("text/calendar")
     mock_get_duties.assert_called_once_with(
-        ANY, 1, from_date=ANY, to_date=ANY, event_types=None
+        ANY, 1, from_date=ANY, to_date=ANY, event_types=["duty"]
     )
-    duties_arg = mock_build_ics.call_args[0][0]
-    assert len(duties_arg) == 3
-    assert duties_arg[0][0].event_type == "duty"
-    assert duties_arg[1][0].event_type == "unavailable"
-    assert duties_arg[2][0].event_type == "vacation"
 
 
 # --- /api/calendar-events ---