addevent-mcp-server

An MCP server that wraps the AddEvent Calendar & Events API v2, so Claude can create, search, retrieve, update, and delete events, calendars, and RSVP attendees on your AddEvent account.

Tools

Events — addevent_create_event, addevent_search_events, addevent_get_event, addevent_update_event, addevent_delete_event

Calendars — addevent_create_calendar, addevent_search_calendars, addevent_get_calendar, addevent_update_calendar, addevent_delete_calendar

RSVP attendees — addevent_create_rsvp, addevent_search_rsvps, addevent_get_rsvp, addevent_update_rsvp, addevent_delete_rsvp

Helper — addevent_list_timezones (looks up valid timezone values for events/calendars)

1. Get your AddEvent API key

Sign in at dashboard.addevent.com, go to Settings > API, and copy the API token. This is the value the server sends as Authorization: Bearer <token> on every request.

2. Run it locally (stdio, for Claude Desktop)

npm install
cp .env.example .env    # then paste your API key into ADDEVENT_API_KEY
npm run build
npm start

To use it from Claude Desktop, add it to your MCP config (Claude Desktop settings > Developer > Edit Config):

{
  "mcpServers": {
    "addevent": {
      "command": "node",
      "args": ["/absolute/path/to/addevent-mcp-server/dist/index.js"],
      "env": {
        "ADDEVENT_API_KEY": "your-api-token-here"
      }
    }
  }
}

3. Deploy to Vercel (remote connector, works from any device)

This mirrors your existing ghl-mcp-remote setup.

npm install -g vercel   # if you don't already have it
vercel login
cd addevent-mcp-server
vercel

Then, in the Vercel project dashboard: Settings > Environment Variables, add ADDEVENT_API_KEY with your token, and redeploy so the function picks it up.

Your MCP endpoint will be:

https://<your-project-name>.vercel.app/api/mcp

Add that URL as a custom connector in Claude (claude.ai > Settings > Connectors, or wherever your workspace manages MCP connectors), the same way ghl-mcp-remote.vercel.app shows up in your tool list now.

4. Test before connecting

The MCP Inspector is the fastest way to sanity-check tool calls before wiring the server into Claude:

npx @modelcontextprotocol/inspector

Point it at node dist/index.js (stdio) or http://localhost:3000/mcp (after running TRANSPORT=http npm start locally).

Notes on the AddEvent API

• Base URL: https://api.addevent.com/calevent/v2. Auth is a Bearer token, not an API-key header.
• Search endpoints return up to page_size (max 20) results per call — use page to page through more.
• The AddEvent docs list the search-calendars response's array key as calendar (singular), which is inconsistent with events and rsvps elsewhere. The client code (src/format.ts, extractArray) checks both calendar and calendars defensively so this doesn't silently return an empty list — worth confirming against a real response the first time you run addevent_search_calendars, and simplifying once confirmed.
• Deleting an event, calendar, or RSVP attendee is permanent — there's no undo or archive endpoint in this API.
• RSVP creation only works on events created with rsvp_enabled: true.

Extending this server

Not covered yet, but straightforward to add if you need them later: calendar subscribers, RSVP forms, and event/calendar landing page templates (all read-only list/search endpoints in the AddEvent API). Follow the pattern in src/tools/timezones.ts for a minimal read-only tool.