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AddEvent MCP by usefulapi

by usefulapi.io · remote · no sign-in to list tools · v1.3.3 · published by io.usefulapi

Read AddEvent calendars, events, RSVPs and subscribers; create and update calendars and events.

Deletes · 3Changes · 3
CompareRegistry entry

18 tools: 3 can delete or cancel things, 3 change things and 12 only read.

Scanned Oct 21, 2026

No check matched anything in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http addevent https://addevent.usefulapi.io/mcp

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

18 tools

Deletes or cancels 3Claude Code: deny
  • addevent_update_calendarWRITE: changes fields of an existing calendar (only the fields you pass; the rest stay).No findings

    Why it is in this group

    • The name "addevent_update_calendar" says "update": a word for a change.
    • The server marks it destructive (destructiveHint: true).
    Description, as the server wrote it
    WRITE: changes fields of an existing calendar (only the fields you pass; the rest stay). Title, description and timezone changes show on its landing page and can reach people who subscribe to the calendar feed. Not reversible by this server (no previous values are kept), so read the calendar first. PATCH /calendars/{id}.

    Annotations the server declares

    • title: Update calendar
    • readOnlyHint: false
    • destructiveHint: true
    • idempotentHint: true
    • openWorldHint: true
  • addevent_update_eventWRITE: changes fields of an existing event (only the fields you pass; the rest stay).No findings

    Why it is in this group

    • The name "addevent_update_event" says "update": a word for a change.
    • The server marks it destructive (destructiveHint: true).
    Description, as the server wrote it
    WRITE: changes fields of an existing event (only the fields you pass; the rest stay). The change goes live on its landing page and share links, and people who subscribed to the calendar or added the event with a live link are updated on their next calendar sync, so a time or location change can notify real people. No previous values are kept: read the event first. PATCH /events/{id}.

    Annotations the server declares

    • title: Update event
    • readOnlyHint: false
    • destructiveHint: true
    • idempotentHint: true
    • openWorldHint: true
  • addevent_update_rsvp_attendeeWRITE: changes ONE RSVP attendee (email, response or form answers; only the fields you pass).No findings

    Why it is in this group

    • The name "addevent_update_rsvp_attendee" says "update": a word for a change.
    • The server marks it destructive (destructiveHint: true).
    Description, as the server wrote it
    WRITE: changes ONE RSVP attendee (email, response or form answers; only the fields you pass). The event's reminder and update e-mails go to the e-mail address stored here, so changing it redirects those e-mails to that person. This server never triggers the confirmation or organizer notification e-mails. PATCH /rsvps/{id}.

    Annotations the server declares

    • title: Update RSVP attendee
    • readOnlyHint: false
    • destructiveHint: true
    • idempotentHint: true
    • openWorldHint: true
Changes things 3Claude Code: ask
  • addevent_create_calendarWRITE: creates a new calendar in the AddEvent account (a new, empty calendar; nothing existing is changed and nobody is notified).No findings

    Why it is in this group

    • The name "addevent_create_calendar" says "create": a word for a change.
    Description, as the server wrote it
    WRITE: creates a new calendar in the AddEvent account (a new, empty calendar; nothing existing is changed and nobody is notified). Needs a title. POST /calendars.

    Annotations the server declares

    • title: Create calendar
    • readOnlyHint: false
    • destructiveHint: false
    • idempotentHint: false
    • openWorldHint: true
  • addevent_create_eventWRITE: creates a new event on a calendar (the account's default calendar if calendar_id is omitted).No findings

    Why it is in this group

    • The name "addevent_create_event" says "create": a word for a change.
    Description, as the server wrote it
    WRITE: creates a new event on a calendar (the account's default calendar if calendar_id is omitted). Creates a public event landing page and share links; it does not e-mail anyone, though people subscribed to that calendar's feed will see the event on their next sync. Needs title and datetime_start. POST /events.

    Annotations the server declares

    • title: Create event
    • readOnlyHint: false
    • destructiveHint: false
    • idempotentHint: false
    • openWorldHint: true
  • addevent_create_rsvp_attendeeWRITE: adds ONE RSVP attendee (one e-mail address, personal data) to an event.No findings

    Why it is in this group

    • The name "addevent_create_rsvp_attendee" says "create": a word for a change.
    Description, as the server wrote it
    WRITE: adds ONE RSVP attendee (one e-mail address, personal data) to an event. This server never asks AddEvent to send the confirmation or organizer notification e-mails, but the event's own reminder and follow-up e-mails (if the event has them) will later go to this address, so only add someone who really RSVP'd. The e-mail must be unique per event. POST /events/{id}/rsvps.

    Annotations the server declares

    • title: Create RSVP attendee
    • readOnlyHint: false
    • destructiveHint: false
    • idempotentHint: false
    • openWorldHint: true
Only reads 12Claude Code: allow
  • addevent_get_calendarOne calendar by id: title, timezone, week start, template ids, subscriber and event counts, links, custom data.No findings

    Why it is in this group

    • The name "addevent_get_calendar" says "get": a word for reading.
    Description, as the server wrote it
    One calendar by id: title, timezone, week start, template ids, subscriber and event counts, links, custom data. GET /calendars/{id}.

    Annotations the server declares

    • title: Get calendar
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_get_calendar_subscriberOne calendar subscriber by id (personal data; IP address and coordinates removed).No findings

    Why it is in this group

    • The name "addevent_get_calendar_subscriber" says "get": a word for reading.
    Description, as the server wrote it
    One calendar subscriber by id (personal data; IP address and coordinates removed). GET /subscribers/{id}.

    Annotations the server declares

    • title: Get calendar subscriber
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_get_eventOne event by id (evt-...): all fields incl.No findings

    Why it is in this group

    • The name "addevent_get_event" says "get": a word for reading.
    Description, as the server wrote it
    One event by id (evt-...): all fields incl. description, organizer, reminder, recurring rule, RSVP settings and stats, custom data and share links. GET /events/{id}.

    Annotations the server declares

    • title: Get event
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_get_rsvp_attendeeOne RSVP attendee by id (personal data: e-mail and form answers; IP address and coordinates removed).No findings

    Why it is in this group

    • The name "addevent_get_rsvp_attendee" says "get": a word for reading.
    Description, as the server wrote it
    One RSVP attendee by id (personal data: e-mail and form answers; IP address and coordinates removed). GET /rsvps/{id}.

    Annotations the server declares

    • title: Get RSVP attendee
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_calendar_subscribersList people subscribed to the account's calendars (personal data: the form answers they gave, such as name and e-mail; calendar app type, sync status).No findings

    Why it is in this group

    • The name "addevent_list_calendar_subscribers" says "list": a word for reading.
    Description, as the server wrote it
    List people subscribed to the account's calendars (personal data: the form answers they gave, such as name and e-mail; calendar app type, sync status). Paged, 20 at most per page. IP address and coordinates are removed. GET /subscribers.

    Annotations the server declares

    • title: List calendar subscribers
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_calendar_templatesThe account's calendar landing page templates or embeddable calendar templates (id, name), newest first.No findings

    Why it is in this group

    • The name "addevent_list_calendar_templates" says "list": a word for reading.
    Description, as the server wrote it
    The account's calendar landing page templates or embeddable calendar templates (id, name), newest first. Use the id as landing_page_template_id / embeddable_calendar_template_id on a calendar. GET /calendars/templates.

    Annotations the server declares

    • title: List calendar templates
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_calendarsList the account's calendars (newest first by default) with id, title, timezone, whether it is the default calendar, landing-page links and counts of events and subscribers.No findings

    Why it is in this group

    • The name "addevent_list_calendars" says "list": a word for reading.
    Description, as the server wrote it
    List the account's calendars (newest first by default) with id, title, timezone, whether it is the default calendar, landing-page links and counts of events and subscribers. GET /calendars.

    Annotations the server declares

    • title: List calendars
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_event_templatesThe account's event landing page templates (id, name), newest first.No findings

    Why it is in this group

    • The name "addevent_list_event_templates" says "list": a word for reading.
    Description, as the server wrote it
    The account's event landing page templates (id, name), newest first. Use the id as landing_page_template_id on an event. GET /events/templates.

    Annotations the server declares

    • title: List event templates
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_eventsSearch the account's events (newest created first; by start time when a date filter is used): title, start/end, timezone, location, RSVP settings and stats, landing-page links.No findings

    Why it is in this group

    • The name "addevent_list_events" says "list": a word for reading.
    Description, as the server wrote it
    Search the account's events (newest created first; by start time when a date filter is used): title, start/end, timezone, location, RSVP settings and stats, landing-page links. Filter by calendar, event ids, text, date window or a custom_data pair. GET /events.

    Annotations the server declares

    • title: List events
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_rsvp_attendeesList RSVP attendees (personal data: e-mail addresses and the answers they gave on the RSVP form).No findings

    Why it is in this group

    • The name "addevent_list_rsvp_attendees" says "list": a word for reading.
    Description, as the server wrote it
    List RSVP attendees (personal data: e-mail addresses and the answers they gave on the RSVP form). Filter by calendar, event or response (going/maybe/not-going). Paged, 20 at most per page: read only what the task needs. IP address and coordinates are removed from the reply. GET /rsvps.

    Annotations the server declares

    • title: List RSVP attendees
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_rsvp_formsThe account's RSVP forms (id, name), newest first.No findings

    Why it is in this group

    • The name "addevent_list_rsvp_forms" says "list": a word for reading.
    Description, as the server wrote it
    The account's RSVP forms (id, name), newest first. Use the id as rsvp_form_id on an event. GET /events/rsvp-forms.

    Annotations the server declares

    • title: List RSVP forms
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true
  • addevent_list_timezonesTimezone names AddEvent supports (use them as the timezone of events and calendars), with current UTC offset.No findings

    Why it is in this group

    • The name "addevent_list_timezones" says "list": a word for reading.
    Description, as the server wrote it
    Timezone names AddEvent supports (use them as the timezone of events and calendars), with current UTC offset. Optional text filter on the name. GET /timezones.

    Annotations the server declares

    • title: List timezones
    • readOnlyHint: true
    • destructiveHint: false
    • openWorldHint: true

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 1.3.3. Values in angle brackets are yours to fill in.

claude mcp add --transport http addevent https://addevent.usefulapi.io/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__addevent__addevent_list_calendars",
      "mcp__addevent__addevent_get_calendar",
      "mcp__addevent__addevent_list_events",
      "mcp__addevent__addevent_get_event",
      "mcp__addevent__addevent_list_rsvp_attendees",
      "mcp__addevent__addevent_get_rsvp_attendee",
      "mcp__addevent__addevent_list_calendar_subscribers",
      "mcp__addevent__addevent_get_calendar_subscriber",
      "mcp__addevent__addevent_list_rsvp_forms",
      "mcp__addevent__addevent_list_event_templates",
      "mcp__addevent__addevent_list_calendar_templates",
      "mcp__addevent__addevent_list_timezones"
    ],
    "ask": [
      "mcp__addevent__addevent_create_calendar",
      "mcp__addevent__addevent_create_event",
      "mcp__addevent__addevent_create_rsvp_attendee"
    ],
    "deny": [
      "mcp__addevent__addevent_update_calendar",
      "mcp__addevent__addevent_update_event",
      "mcp__addevent__addevent_update_rsvp_attendee"
    ]
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as addevent. Review it before you use it.