# Teamup Calendar MCP by usefulapi (remote · teamup-calendar.usefulapi.io)

Read and search Teamup Calendar events and sub-calendars; create, update, delete and undo events.

- Trust score: 63/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-17

## Components

- remote · `teamup-calendar.usefulapi.io`: 63/100 (this document), [markdown](https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar.md), [page](https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar)

## Channel facts

- Endpoint: `https://teamup-calendar.usefulapi.io/mcp`
- Transports: `streamable-http`
- Auth: `required`
- Version: `1.0.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-17.

- **Endpoint Security**: 78/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation is enforced on tool calls, advertised via RFC 9728 protected-resource metadata. Discovery is public, which costs nothing: no tool can be invoked without a token.
  - HTTPS enforcement could not be verified: the plaintext port redirected somewhere other than https, so enforcement is unproven.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
  - The authorisation server offers only Dynamic Client Registration (RFC 7591), which MCP 2026-07-28 deprecated in favour of Client ID Metadata Documents.
- **Transport & Reachability**: 0/100
  - Transport check failed: declared streamable-http, but the endpoint redirected instead of responding directly.
- **Schema Quality & AI Usability**: 78/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 2540 tokens (~169/item across 15 items; 15 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 17/100
  - Stability observed for 5 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 93/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 80% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.
  - An AI judge read all 16 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 60/100
  - Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28.

## Install

### How do I install the Teamup Calendar MCP by usefulapi server?

Teamup Calendar MCP by usefulapi is a hosted endpoint at https://teamup-calendar.usefulapi.io/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http io-usefulapi-teamup-calendar 'https://teamup-calendar.usefulapi.io/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "io-usefulapi-teamup-calendar": {
      "url": "https://teamup-calendar.usefulapi.io/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "io-usefulapi-teamup-calendar": {
      "type": "http",
      "url": "https://teamup-calendar.usefulapi.io/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.io-usefulapi-teamup-calendar]
url = "https://teamup-calendar.usefulapi.io/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-usefulapi-teamup-calendar": {
      "type": "remote",
      "url": "https://teamup-calendar.usefulapi.io/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add io-usefulapi-teamup-calendar --url 'https://teamup-calendar.usefulapi.io/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  io-usefulapi-teamup-calendar:
    url: "https://teamup-calendar.usefulapi.io/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "io-usefulapi-teamup-calendar": {
      "Transport": "http",
      "Url": "https://teamup-calendar.usefulapi.io/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add io-usefulapi-teamup-calendar -t streamable-http -u 'https://teamup-calendar.usefulapi.io/mcp'
```

### Other

```json
{
  "mcpServers": {
    "io-usefulapi-teamup-calendar": {
      "type": "http",
      "url": "https://teamup-calendar.usefulapi.io/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-10-16 (score 63, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-14 (score 62, +3)

- [security] The server rewrote its instructions, which are the text every model session reads
- [functional] The server now declares the “prompts” capability
- [functional] First check of Schema quality: 100
- [functional] New prompt “getting_started”
- [functional] Server version: 1.0.0 → 1.1.0

### 2026-10-13 (score 59, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-10-12 (score 59)

First indexed and scored.

## MCP tools (15)

### `teamup_get_calendar` (~76 tokens)

Get calendar

The calendar this connection points at: title, timezone and date settings, custom event fields, sub-calendars, the permission of the calendar key in use and the plan's features. Call this first to learn the sub-calendar ids and the timezone. The calendar key itself is never returned. GET /{calendarKey}/configuration.

### `teamup_list_subcalendars` (~136 tokens)

List sub-calendars

List the sub-calendars (the colored lanes that events belong to, such as people, rooms or resources). A key with admin permission also sees inactive ones. GET /{calendarKey}/subcalendars.

Input parameters:

- `include_inactive` (boolean): Include inactive sub-calendars (default false).
- `limit` (integer): Results per page, 1-200 (default 50).
- `name_contains` (string): Only sub-calendars whose name matches this text.
- `offset` (integer): Number of results to skip (default 0). Pass the previous reply's next_offset.

### `teamup_get_subcalendar` (~58 tokens)

Get sub-calendar

One sub-calendar by id: name, color, overlap rule, active state and which links may use it. GET /{calendarKey}/subcalendars/{id}.

Input parameters:

- `subcalendar_id` (integer, required): Sub-calendar id.

### `teamup_list_access_keys` (~149 tokens)

List access keys

List the calendar's access keys (sharing links and user accesses) with name, role, active state and per-sub-calendar permission. Needs a key with admin permission. The secret key values are never returned (they are secrets); use the id and name to tell links apart. GET /{calendarKey}/keys.

Input parameters:

- `limit` (integer): Results per page, 1-200 (default 50).
- `name_contains` (string): Only keys whose link, user or group name matches this text.
- `offset` (integer): Number of results to skip (default 0). Pass the previous reply's next_offset.
- `type` (string): Only this kind of access.

### `teamup_list_events` (~176 tokens)

List events

List the events in a date range, optionally only on some sub-calendars. Recurring events are expanded: every occurrence in the range is returned with its own id (series id + -rid- + start). Notes come as markdown. Times use the calendar's timezone unless tz is set. GET /{calendarKey}/events.

Input parameters:

- `end_date` (string): Last day, inclusive, yyyy-mm-dd (default: start_date). Needs start_date; at most 366 days after it.
- `start_date` (string): First day, yyyy-mm-dd (default: today).
- `subcalendar_ids` (array): Only events on these sub-calendars.
- `tz` (string): Timezone for the times in the reply, e.g. Europe/Berlin. Default: the calendar's timezone.

### `teamup_search_events` (~219 tokens)

Search events

Search events by keyword (2-100 characters) within a date range (default: today only, so always pass the range you mean). Recurring events are expanded. Paged with limit and offset. GET /{calendarKey}/events?query=.

Input parameters:

- `end_date` (string): Last day, inclusive, yyyy-mm-dd (default: start_date). Needs start_date; at most 366 days after it.
- `limit` (integer): Results per page, 1-200 (default 50).
- `offset` (integer): Number of results to skip (default 0). Pass the previous reply's next_offset.
- `query` (string, required): Search text (Teamup's search syntax applies).
- `start_date` (string): First day, yyyy-mm-dd (default: today).
- `subcalendar_ids` (array): Only events on these sub-calendars.
- `tz` (string): Timezone for the times in the reply, e.g. Europe/Berlin. Default: the calendar's timezone.

### `teamup_get_event` (~95 tokens)

Get event

One event by id: title, times, sub-calendars, location, who, notes (markdown), recurrence rule, custom fields, signups, comments, attachments (metadata), version, change history and reminders. Use the occurrence id (123-rid-<unix start>) for one occurrence of a recurring event. GET /{calendarKey}/events/{id}.

Input parameters:

- `event_id` (string, required): Event id.

### `teamup_list_changed_events` (~129 tokens)

List changed events

Events created, changed or deleted since a Unix timestamp (at most 30 days back), for syncing. A recurring event comes back once, as its series, not as occurrences. Deleted events carry delete_dt. Pass the reply's timestamp as since_timestamp next time so nothing is missed. GET /{calendarKey}/events?modifiedSince=.

Input parameters:

- `mode` (string): synchronize (default): events created and deleted after the timestamp are left out. monitor: they are returned too.
- `since_timestamp` (integer, required): Unix timestamp in seconds, at most 30 days in the past.

### `teamup_list_event_signups` (~58 tokens)

List event signups

The people signed up for an event (name, email, id). Signups must be enabled on the event. GET /{calendarKey}/events/{id}/signups.

Input parameters:

- `event_id` (string, required): Event id.

### `teamup_create_event` (~382 tokens)

Create event

WRITE: create an event. Needs a calendar key with add or modify permission. Give at least subcalendar_ids, start and end. Not idempotent: a repeated call creates a second event. The reply holds the new event and an undo_id; teamup_undo_event_action removes the event again within one hour. POST /{calendarKey}/events.

Input parameters:

- `all_day` (boolean): True for an all-day event (default false).
- `comments_enabled` (boolean): Allow comments (default false).
- `comments_visibility` (string): Who sees the comments: all_users or users_with_modify_permission.
- `custom` (object): Values of custom fields, keyed by field id (see teamup_get_calendar -> fields).
- `end` (string, required): End, same format as start. Must not be before start.
- `location` (string)
- `notes` (string): Notes, in markdown.
- `rrule` (string): Recurrence rule (iCalendar RRULE, e.g. FREQ=WEEKLY;COUNT=10). Omit for a single event.
- `signup_enabled` (boolean): Let people sign up (default false).
- `signup_limit` (integer): Maximum signups; required by Teamup when signup_enabled is true.
- `signup_visibility` (string): Who sees the signups: all_users or users_with_modify_permission.
- `start` (string, required): Start, e.g. 2026-10-14T09:00:00 (calendar timezone) or with an offset such as +02:00. For an all-day event: yyyy-mm-dd.
- `subcalendar_ids` (array, required): Sub-calendar ids the event belongs to (from teamup_list_subcalendars).
- `title` (string): Event title.
- `who` (string): The "who" field.

### `teamup_update_event` (~371 tokens)

Update event

WRITE: change fields of an event; fields you leave out keep their value (the event is read first and sent back with its version, so a concurrent edit is refused instead of overwritten; an event without a version is not changed). Needs modify permission. For a recurring event pass redit; use the occurrence id (123-rid-<unix start>) with single or future. Attachments are not touched. The reply holds the event and an undo_id for one hour (teamup_undo_event_action). PUT /{calendarKey}/events/{id}.

Input parameters:

- `all_day` (boolean)
- `comments_enabled` (boolean)
- `comments_visibility` (string)
- `custom` (object): Custom field values to set, keyed by field id; other custom fields keep their value.
- `end` (string): New end.
- `event_id` (string, required): Event id (occurrence id for one occurrence of a recurring event).
- `location` (string)
- `notes` (string): New notes, in markdown. Replaces the old notes.
- `redit` (string): Which occurrences of a recurring event: single (only this one), future (this and all later ones) or all.
- `rrule` (string): New recurrence rule; with redit all or future only. An empty string removes the recurrence (the series becomes a single event).
- `signup_enabled` (boolean)
- `signup_limit` (integer)
- `signup_visibility` (string)
- `start` (string): New start (same formats as in teamup_create_event).
- `subcalendar_ids` (array): Sub-calendar ids the event belongs to (from teamup_list_subcalendars).
- `title` (string)
- `who` (string)

### `teamup_delete_event` (~185 tokens)

Delete event

WRITE, DESTRUCTIVE: delete an event, or for a recurring event the chosen occurrences. Needs modify permission. Not retried. The reply holds an undo_id; teamup_undo_event_action restores the event within one hour, after that the deletion is permanent. For one occurrence use the occurrence id (123-rid-<unix start>) and redit single (the default); redit all deletes the whole series. DELETE /{calendarKey}/events/{id}.

Input parameters:

- `event_id` (string, required): Event id (occurrence id for one occurrence of a recurring event).
- `redit` (string): For a recurring event: single (default), future or all. With all the whole series is deleted.
- `version` (string): The event's version (from teamup_get_event). If set, the delete is refused when the event changed since.

### `teamup_undo_event_action` (~78 tokens)

Undo event change

WRITE: undo a recent event creation, update or deletion with the undo_id from that call. Works for one hour only and is refused if someone else changed the event since. PUT /{calendarKey}/events/undo/{undo_id}.

Input parameters:

- `undo_id` (string, required): The undo_id returned by create, update or delete.

### `teamup_create_subcalendar` (~113 tokens)

Create sub-calendar

WRITE: create a sub-calendar. Needs a calendar key with admin permission, and the plan may limit how many exist. Not idempotent: a repeated call creates a second one. POST /{calendarKey}/subcalendars.

Input parameters:

- `active` (boolean): Active (default true).
- `color` (integer): Color number from Teamup's palette (default 17).
- `name` (string, required): Sub-calendar name.
- `overlap` (boolean): Allow overlapping events on it (default true).

### `teamup_update_subcalendar` (~106 tokens)

Update sub-calendar

WRITE: change a sub-calendar's name, color, overlap rule or active state; fields you leave out keep their value. Needs admin permission. Making a sub-calendar inactive hides it from users without admin rights. PATCH /{calendarKey}/subcalendars/{id}.

Input parameters:

- `active` (boolean)
- `color` (integer)
- `name` (string)
- `overlap` (boolean)
- `subcalendar_id` (integer, required): Sub-calendar id.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar#diagnostics

## Score history

- 2026-10-17: 63
- 2026-10-16: 63
- 2026-10-15: 62
- 2026-10-14: 62
- 2026-10-13: 59
- 2026-10-12: 59

## Common questions

### What is the Teamup Calendar MCP by usefulapi server?

Teamup Calendar MCP by usefulapi is listed in the public MCP registry as io.usefulapi/teamup-calendar. Read and search Teamup Calendar events and sub-calendars; create, update, delete and undo events. This page covers its hosted endpoint (https://teamup-calendar.usefulapi.io/mcp).

### Is the Teamup Calendar MCP by usefulapi server safe to use?

Teamup Calendar MCP by usefulapi scores 63 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the Teamup Calendar MCP by usefulapi server expose?

Teamup Calendar MCP by usefulapi exposes 15 tools: teamup_get_calendar, teamup_list_subcalendars, teamup_get_subcalendar, teamup_list_access_keys, teamup_list_events, and 10 more. Their descriptions and schemas cost roughly 2,331 tokens of context every time the server is loaded.

### Does the Teamup Calendar MCP by usefulapi server require authentication?

Yes. Teamup Calendar MCP by usefulapi asked us for credentials when we connected, so you will need to authorise it in your MCP client before it can do anything.

### Is the Teamup Calendar MCP by usefulapi server still maintained?

Teamup Calendar MCP by usefulapi is still listed as active in the MCP registry. We last reached this channel on 17 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://teamup-calendar.usefulapi.io/mcp
- Repository: https://github.com/m190/usefulapi-mcp
- Website: https://usefulapi.io/teamup-calendar/
- Changelog RSS feed: https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar.xml
- Changelog JSON feed: https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar.json
- HTML version of this page: https://verifymcp.io/servers/io-usefulapi-teamup-calendar/teamup-calendar