fix(outlook-mcp): calendar list uses configured timezone and merge duplicate select fields

calendar/list.js

@@ -61,8 +61,17 @@ async function handleListEvents(args) {
     
     // Format results
     const eventList = response.value.map((event, index) => {
-      const startDate = formatDateTime(event.start.dateTime, event.start.timeZone);
+      // Graph stores timed events in UTC and returns dateTime without a 'Z' suffix.
-      const endDate = formatDateTime(event.end.dateTime, event.end.timeZone);
+      // Normalize to UTC so the display matches the stored instant regardless of
+      // the container's default timezone.
+      const startDate = formatDateTime(
+        normalizeGraphDateTime(event.start.dateTime, event.start.timeZone),
+        config.DEFAULT_TIMEZONE
+      );
+      const endDate = formatDateTime(
+        normalizeGraphDateTime(event.end.dateTime, event.end.timeZone),
+        config.DEFAULT_TIMEZONE
+      );
       const location = event.location.displayName || 'No location';
       
       return `${index + 1}. ${event.subject} - Location: ${location}\nStart: ${startDate}\nEnd: ${endDate}\nSubject: ${event.subject}\nSummary: ${event.bodyPreview}\nID: ${event.id}\n`;
@@ -93,4 +102,21 @@ async function handleListEvents(args) {
   }
 }
 
+/**
+ * Ensure a Graph dateTime string is parsed as the intended instant.
+ * Graph returns timed events in UTC with no Z suffix; append Z so Node parses
+ * it as UTC rather than as the container's local timezone.
+ * @param {string} dateTime - Graph dateTime value
+ * @param {string} timeZone - Graph timeZone value
+ * @returns {string} - Date string safe for new Date()/toLocaleString
+ */
+function normalizeGraphDateTime(dateTime, timeZone) {
+  if (!dateTime) return dateTime;
+  const hasOffset = /Z|[+-]\d{2}:\d{2}$|[+-]\d{4}$/.test(dateTime);
+  if (!hasOffset && timeZone === 'UTC') {
+    return `${dateTime}Z`;
+  }
+  return dateTime;
+}
+
 module.exports = handleListEvents;

config.js

@@ -34,15 +34,12 @@ module.exports = {
   GRAPH_API_ENDPOINT: 'https://graph.microsoft.com/v1.0/',
   
   // Calendar constants
-  CALENDAR_SELECT_FIELDS: 'id,subject,start,end,location,bodyPreview,isAllDay,recurrence,attendees',
+  CALENDAR_SELECT_FIELDS: 'id,subject,bodyPreview,start,end,location,organizer,attendees,isAllDay,isCancelled,recurrence',
 
   // Email constants
   EMAIL_SELECT_FIELDS: 'id,subject,from,toRecipients,ccRecipients,receivedDateTime,bodyPreview,hasAttachments,importance,isRead,conversationId',
   EMAIL_DETAIL_FIELDS: 'id,subject,from,toRecipients,ccRecipients,bccRecipients,receivedDateTime,bodyPreview,body,hasAttachments,importance,isRead,internetMessageHeaders',
   
-  // Calendar constants
-  CALENDAR_SELECT_FIELDS: 'id,subject,bodyPreview,start,end,location,organizer,attendees,isAllDay,isCancelled',
-  
   // Default timezone for calendar event creation and display (IANA tz name, e.g. 'America/New_York').
   // Override via MS_TIMEZONE env var. Graph API accepts IANA timezone identifiers.
   DEFAULT_TIMEZONE: process.env.MS_TIMEZONE || 'America/New_York',

utils/time-formatter.js

@@ -2,7 +2,7 @@
  * Timezone-aware date formatting utilities for Outlook MCP Server.
  *
  * All user-visible timestamps are formatted in the configured timezone
- * (MS_TIMEZONE env var, default Eastern Standard Time) so that dates
+ * (MS_TIMEZONE env var, default America/New_York) so that dates
  * rendered inside the UTC container still match the user's local time.
  */
 const config = require('../config');