fix(calendar): respect configured timezone

templates/calendar/actions/get-settings.ts

@@ -1,9 +1,8 @@
 import { defineAction } from "@agent-native/core";
 import { getRequestUserEmail } from "@agent-native/core/server";
-import { getUserSetting } from "@agent-native/core/settings";
 import { z } from "zod";
 
-import { normalizeCalendarSettings } from "../shared/settings.js";
+import { readCalendarSettings } from "../server/lib/calendar-settings.js";
 
 export default defineAction({
   description: "Get calendar settings",
@@ -12,8 +11,6 @@ export default defineAction({
   run: async () => {
     const email = getRequestUserEmail();
     if (!email) throw new Error("no authenticated user");
-    return normalizeCalendarSettings(
-      await getUserSetting(email, "calendar-settings"),
-    );
+    return readCalendarSettings(email);
   },
 });

templates/calendar/actions/list-events.test.ts

@@ -1,4 +1,4 @@
-import { beforeEach, describe, expect, it, vi } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
 const getRequestTimezoneMock = vi.hoisted(() => vi.fn());
 const getRequestUserEmailMock = vi.hoisted(() => vi.fn());
@@ -252,6 +252,10 @@ describe("list-events inventory contract", () => {
     verifyShortLivedTokenMock.mockReturnValue({ ok: true });
   });
 
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
   it("keeps legacy callers on CalendarEvent arrays", async () => {
     const result = await (listEventsAction as any).run(
       { from: "2026-06-17", to: "2026-06-18" },
@@ -704,6 +708,62 @@ describe("list-events inventory contract", () => {
     expect(listGoogleEventsMock).not.toHaveBeenCalled();
   });
 
+  it("uses the saved timezone for omitted-range inventory cursors", async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date("2026-06-17T12:00:00.000Z"));
+    getRequestTimezoneMock.mockReturnValue("UTC");
+    getUserSettingMock.mockResolvedValue({ timezone: "America/New_York" });
+    listGoogleEventsMock.mockResolvedValue({
+      events: [
+        {
+          id: "google-event-1",
+          googleEventId: "event-1",
+          title: "First",
+          description: "",
+          start: "2026-06-17T16:00:00.000Z",
+          end: "2026-06-17T16:30:00.000Z",
+          location: "",
+          allDay: false,
+          source: "google",
+          accountEmail: "steve@example.com",
+          createdAt: "2026-06-12T10:13:39.746Z",
+          updatedAt: "2026-06-12T10:13:39.746Z",
+        },
+        {
+          id: "google-event-2",
+          googleEventId: "event-2",
+          title: "Second",
+          description: "",
+          start: "2026-06-17T17:00:00.000Z",
+          end: "2026-06-17T17:30:00.000Z",
+          location: "",
+          allDay: false,
+          source: "google",
+          accountEmail: "steve@example.com",
+          createdAt: "2026-06-12T10:13:39.746Z",
+          updatedAt: "2026-06-12T10:13:39.746Z",
+        },
+      ],
+      errors: [],
+    });
+
+    const first = await (listEventsAction as any).run(
+      { format: "inventory", pageSize: 1, sources: ["google"] },
+      { caller: "mcp" },
+    );
+    const second = await (listEventsAction as any).run(
+      {
+        format: "inventory",
+        pageSize: 1,
+        sources: ["google"],
+        cursor: first.page.nextCursor,
+      },
+      { caller: "mcp" },
+    );
+
+    expect(second.items.map((item: any) => item.id)).toEqual(["event-2"]);
+  });
+
   it("rejects a malformed inventory cursor before provider reads", async () => {
     await expect(
       (listEventsAction as any).run(

templates/calendar/actions/list-events.ts

@@ -13,9 +13,16 @@
 import { z } from "zod";
 
 import { getDb, schema } from "../server/db/index.js";
+import { getCalendarTimezone } from "../server/lib/calendar-settings.js";
 import * as googleCalendar from "../server/lib/google-calendar.js";
 import { fetchICalEvents } from "../server/lib/ical-fetcher.js";
 import type { CalendarEvent, ExternalCalendar } from "../shared/api.js";
+import {
+  addDaysToDateKey,
+  dateKeyInTimezone,
+  dateTimeInTimezoneToIso,
+  isCalendarTimezone,
+} from "../shared/timezone.js";
 import { calendarEventMatchesQuery } from "./event-search.js";
 
 const DATE_ONLY_RE = /^\d{4}-\d{2}-\d{2}$/;
@@ -74,6 +81,7 @@
 interface ListCalendarEventsOptions {
   ownedAccounts?: string[];
   range?: CalendarEventRange;
+  timezone?: string;
 }
 
 type CalendarInventorySource = "google" | "bookings" | "ics" | "overlays";
@@ -156,7 +164,7 @@
 function sanitizeError(message: unknown, fallback: string) {
   return (
     cap(
       String(message ?? fallback)
         .replace(/\bBearer\s+\S+/gi, "Bearer [redacted]")
         .replace(
           /\b(access_token|refresh_token|id_token|token)=([^\s&]+)/gi,
@@ -346,84 +354,9 @@
   };
 }
 
-function normalizeTimezone(timezone?: string): string {
-  if (!timezone) return "UTC";
-  try {
-    new Intl.DateTimeFormat("en-US", { timeZone: timezone }).format();
-    return timezone;
-  } catch {
-    return "UTC";
-  }
-}
-
-function datePartsInTimezone(date: Date, timezone: string) {
-  const parts = new Intl.DateTimeFormat("en-US", {
-    timeZone: timezone,
-    hourCycle: "h23",
-    year: "numeric",
-    month: "2-digit",
-    day: "2-digit",
-    hour: "2-digit",
-    minute: "2-digit",
-    second: "2-digit",
-  }).formatToParts(date);
-  const get = (type: string) =>
-    Number(parts.find((part) => part.type === type)?.value ?? "0");
-  return {
-    year: get("year"),
-    month: get("month"),
-    day: get("day"),
-    hour: get("hour"),
-    minute: get("minute"),
-    second: get("second"),
-  };
-}
-
-function dateOnlyInTimezone(date: Date, timezone: string): string {
-  const parts = datePartsInTimezone(date, timezone);
-  return [
-    String(parts.year).padStart(4, "0"),
-    String(parts.month).padStart(2, "0"),
-    String(parts.day).padStart(2, "0"),
-  ].join("-");
-}
-
-function addDaysToDateOnly(dateOnly: string, days: number): string {
-  const [year, month, day] = dateOnly.split("-").map(Number);
-  const date = new Date(Date.UTC(year, month - 1, day + days));
-  return [
-    String(date.getUTCFullYear()).padStart(4, "0"),
-    String(date.getUTCMonth() + 1).padStart(2, "0"),
-    String(date.getUTCDate()).padStart(2, "0"),
-  ].join("-");
-}
-
-function offsetMsForTimezone(date: Date, timezone: string): number {
-  const parts = datePartsInTimezone(date, timezone);
-  const asUtc = Date.UTC(
-    parts.year,
-    parts.month - 1,
-    parts.day,
-    parts.hour,
-    parts.minute,
-    parts.second,
-  );
-  return asUtc - date.getTime();
-}
-
-function zonedDateOnlyToUtcIso(dateOnly: string, timezone: string): string {
-  const [year, month, day] = dateOnly.split("-").map(Number);
-  const wallClockUtc = Date.UTC(year, month - 1, day, 0, 0, 0);
-  const firstGuess = new Date(wallClockUtc);
-  const firstOffset = offsetMsForTimezone(firstGuess, timezone);
-  const secondGuess = new Date(wallClockUtc - firstOffset);
-  const secondOffset = offsetMsForTimezone(secondGuess, timezone);
-  return new Date(wallClockUtc - secondOffset).toISOString();
-}
-
 function normalizeDateBound(value: string, timezone: string): string {
   if (DATE_ONLY_RE.test(value)) {
-    return zonedDateOnlyToUtcIso(value, timezone);
+    return dateTimeInTimezoneToIso(value, "00:00", timezone);
   }
   const parsed = new Date(value);
   if (Number.isNaN(parsed.getTime())) {
@@ -437,19 +370,20 @@
   to?: string;
   timezone?: string;
 }): CalendarEventRange {
-  const timezone = normalizeTimezone(args.timezone ?? getRequestTimezone());
-  const today = dateOnlyInTimezone(new Date(), timezone);
+  const requested = args.timezone ?? getRequestTimezone();
+  const timezone = isCalendarTimezone(requested) ? requested : "UTC";
+  const today = dateKeyInTimezone(new Date(), timezone);
   let from = args.from?.trim();
   let to = args.to?.trim();
   let defaulted = false;
 
   if (!from && !to) {
     from = today;
-    to = addDaysToDateOnly(today, 1);
+    to = addDaysToDateKey(today, 1);
     defaulted = true;
   } else if (from && !to) {
     if (DATE_ONLY_RE.test(from)) {
-      to = addDaysToDateOnly(from, 1);
+      to = addDaysToDateKey(from, 1);
     } else {
       const start = new Date(from);
       if (Number.isNaN(start.getTime())) {
@@ -578,11 +512,13 @@
 ): Promise<CalendarEventsResult> {
   const email = getRequestUserEmail();
   if (!email) throw new Error("no authenticated user");
+  const timezone = options.timezone ?? (await getCalendarTimezone(email));
   const range =
     options.range ??
     resolveCalendarEventRange({
       from: args.from,
       to: args.to,
+      timezone,
     });
 
   const sources = resolveInventorySources(args.sources);
@@ -829,6 +765,9 @@
       args.format === "inventory" || (ctx?.caller === "mcp" && !args.format);
     const owner = inventory ? getRequestUserEmail() : undefined;
     if (inventory && !owner) throw new Error("no authenticated user");
+    const calendarTimezone = inventory
+      ? await getCalendarTimezone(owner!)
+      : undefined;
 
     // Reject invalid, expired, owner-bound, and query-bound cursors before any
     // provider call. Omitted account filters require the cheap owned-account
@@ -842,6 +781,7 @@
       preparedRange = resolveCalendarEventRange({
         from: args.from,
         to: args.to,
+        timezone: calendarTimezone,
       });
       preparedOwnedAccounts = args.accountEmails
         ? undefined
@@ -868,6 +808,7 @@
       {
         ownedAccounts: preparedOwnedAccounts,
         range: preparedRange,
+        timezone: calendarTimezone,
       },
     );
 

templates/calendar/actions/update-settings.ts

@@ -1,18 +1,21 @@
 import { defineAction } from "@agent-native/core";
 import { getRequestUserEmail } from "@agent-native/core/server";
-import {
-  getUserSetting,
-  putUserSetting,
-  putSetting,
-} from "@agent-native/core/settings";
 import { z } from "zod";
 
-import { normalizeCalendarSettings } from "../shared/settings.js";
+import { saveCalendarSettings } from "../server/lib/calendar-settings.js";
+import { isCalendarTimezone } from "../shared/timezone.js";
 
 export default defineAction({
   description: "Update calendar settings",
   schema: z.object({
-    timezone: z.string().optional().describe("Timezone"),
+    timezone: z
+      .string()
+      .trim()
+      .refine(isCalendarTimezone, {
+        message: "Timezone must be a valid IANA timezone.",
+      })
+      .optional()
+      .describe("IANA timezone, e.g. Europe/Warsaw"),
     bookingPageTitle: z.string().optional().describe("Booking page title"),
     bookingPageDescription: z
       .string()
@@ -32,14 +35,6 @@ export default defineAction({
   run: async (args) => {
     const email = getRequestUserEmail();
     if (!email) throw new Error("no authenticated user");
-    const currentSettings = await getUserSetting(email, "calendar-settings");
-    const settings = normalizeCalendarSettings({
-      ...normalizeCalendarSettings(currentSettings),
-      ...args,
-    });
-    const settingsRecord = settings as unknown as Record<string, unknown>;
-    await putUserSetting(email, "calendar-settings", settingsRecord);
-    await putSetting("calendar-settings", settingsRecord);
-    return settings;
+    return saveCalendarSettings(email, args);
   },
 });

templates/calendar/actions/view-screen.ts

@@ -6,11 +6,17 @@
 
 import { getDb, schema } from "../server/db/index.js";
 import { rowToBookingLink } from "../server/lib/booking-link-utils.js";
+import { getCalendarTimezone } from "../server/lib/calendar-settings.js";
 import type { CalendarEvent, CalendarEventDraft } from "../shared/api.js";
 import {
   CALENDAR_VIEW_PREFERENCES_KEY,
   normalizeCalendarViewPreferences,
 } from "../shared/calendar-view-preferences.js";
+import {
+  addDaysToDateKey,
+  dateKeyInTimezone,
+  dateTimeInTimezoneToIso,
+} from "../shared/timezone.js";
 import { extractVideoLink } from "./event-action-helpers.js";
 import { listCalendarEvents } from "./list-events.js";
 
@@ -49,6 +55,11 @@
   }
 }
 
+function dateKeyFromParts(date: Date): string {
+  const pad = (value: number) => String(value).padStart(2, "0");
+  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}`;
+}
+
 export default defineAction({
   description:
     "See what the user is currently looking at on screen. Returns the current view, date range, and visible events. Always call this first before taking any action.",
@@ -67,18 +78,22 @@
     const nav = navigation as any;
 
     if (nav?.view === "calendar" || !nav?.view) {
-      const now = new Date();
-      const viewDate = nav?.date ? new Date(nav.date) : now;
-
-      const from = new Date(viewDate);
-      from.setDate(from.getDate() - from.getDay());
-      from.setHours(0, 0, 0, 0);
-      const to = new Date(from);
-      to.setDate(to.getDate() + 7);
+      const email = getRequestUserEmail();
+      if (!email) throw new Error("no authenticated user");
+      const timezone = await getCalendarTimezone(email);
+      // Work in calendar days, then resolve the two edges to instants once.
+      const viewDay = nav?.date ?? dateKeyInTimezone(new Date(), timezone);
+      // Noon UTC so the weekday can never be shifted by an offset.
+      const weekday = new Date(`${viewDay}T12:00:00Z`).getUTCDay();
+      const weekStart = addDaysToDateKey(viewDay, -weekday);
 
       const eventResult = await fetchEventsForRange(
-        from.toISOString(),
-        to.toISOString(),
+        dateTimeInTimezoneToIso(weekStart, "00:00", timezone),
+        dateTimeInTimezoneToIso(
+          addDaysToDateKey(weekStart, 7),
+          "00:00",
+          timezone,
+        ),
       );
       const { events } = eventResult;