# io.github.physics-star-cat/databutler-calendar (remote · databutler.dev)

Public holidays (UK, US, DE, FR), tax-year dates and DST switches for 2026-2028.

- Trust score: 33/100 (low)
- Change this week: −49
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `databutler.dev`: 33/100 (this document), [markdown](https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar.md), [page](https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar)

## Channel facts

- Endpoint: `https://databutler.dev/api/mcp/calendar`
- Transports: `streamable-http`
- Auth: `required (not validated)`
- 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 2026-11-05.

- **Endpoint Security**: 83/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - The endpoint enforces authorisation, but returns a challenge with no valid RFC 9728 metadata, so a client cannot discover where to get a token.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 0/100
  - Transport blocked by authentication: the endpoint requires auth we don't have to verify streamable-http.
- **Schema Quality & AI Usability**: 0/100
  - Schema blocked by authentication: the endpoint requires auth we don't have to read it.
- **Stability & Change Management**: 0/100
  - Stability not yet verified: not enough scan history yet (needs a 30-day window).
- **Tool Coverage**: 0/100
  - Tool coverage blocked by authentication: the endpoint requires auth we don't have to read its tools.
- **Tool Safety**: 0/100
  - Tool safety blocked by authentication: the endpoint requires auth we don't have to read its tools.
- **Capabilities**: 0/100
  - Capabilities blocked by authentication: the endpoint requires auth we don't have to read them.

**Unverified: 6 categories.** Categories scored 0 because we could not verify them: authentication we do not have, an unreachable endpoint, or not enough scan history. We only credit what we can confirm.

## Install

### How do I install the io.github.physics-star-cat/databutler-calendar MCP server?

io.github.physics-star-cat/databutler-calendar is a hosted endpoint at https://databutler.dev/api/mcp/calendar, 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 physics-star-cat-databutler-calendar 'https://databutler.dev/api/mcp/calendar'
```

### Cursor

```json
{
  "mcpServers": {
    "physics-star-cat-databutler-calendar": {
      "url": "https://databutler.dev/api/mcp/calendar"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "physics-star-cat-databutler-calendar": {
      "type": "http",
      "url": "https://databutler.dev/api/mcp/calendar"
    }
  }
}
```

### Codex

```toml
[mcp_servers.physics-star-cat-databutler-calendar]
url = "https://databutler.dev/api/mcp/calendar"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "physics-star-cat-databutler-calendar": {
      "type": "remote",
      "url": "https://databutler.dev/api/mcp/calendar",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add physics-star-cat-databutler-calendar --url 'https://databutler.dev/api/mcp/calendar' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  physics-star-cat-databutler-calendar:
    url: "https://databutler.dev/api/mcp/calendar"
```

### Netclaw

```json
{
  "McpServers": {
    "physics-star-cat-databutler-calendar": {
      "Transport": "http",
      "Url": "https://databutler.dev/api/mcp/calendar"
    }
  }
}
```

### Vellum

```bash
assistant mcp add physics-star-cat-databutler-calendar -t streamable-http -u 'https://databutler.dev/api/mcp/calendar'
```

### Other

```json
{
  "mcpServers": {
    "physics-star-cat-databutler-calendar": {
      "type": "http",
      "url": "https://databutler.dev/api/mcp/calendar"
    }
  }
}
```

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.

### 2026-11-01 (score 33, −50)

- [security regression] Endpoint reachability: reachable → behind authorisation
- [security regression] Tool safety: pass → unverified
- [security regression] Transport: pass → unverified
- [security regression] Stability: 0.90 → unverified
- [security regression] Authorization: partial → fail
- [security regression] HSTS header: pass → fail
- [functional regression] Capabilities: pass → unverified
- [functional regression] Tool coverage: 100 → unverified
- [functional] First check of Schema quality: unverified

### 2026-10-30 (score 83, +1)

No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-28 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 77 to 80. That category is still filling its 30-day observation window: 23 days of observed history at the previous scan, 24 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-26 (score 81, +1)

No change was recorded against any check on this day. Stability & Change Management went from 70 to 73. That category is still filling its 30-day observation window: 21 days of observed history at the previous scan, 22 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-24 (score 80, +1)

No change was recorded against any check on this day. Stability & Change Management went from 63 to 67. That category is still filling its 30-day observation window: 19 days of observed history at the previous scan, 20 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-22 (score 79, +1)

No change was recorded against any check on this day. Stability & Change Management went from 57 to 60. That category is still filling its 30-day observation window: 17 days of observed history at the previous scan, 18 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-20 (score 78, +1)

No change was recorded against any check on this day. Stability & Change Management went from 50 to 53. That category is still filling its 30-day observation window: 15 days of observed history at the previous scan, 16 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-18 (score 77, +1)

No change was recorded against any check on this day. Stability & Change Management went from 43 to 47. That category is still filling its 30-day observation window: 13 days of observed history at the previous scan, 14 at this one. The score rises as the window fills, whether or not the server changes.

## MCP tools (2)

### `calendar_facts` (~465 tokens)

Calendar facts lookup

Public holidays, tax-year dates or daylight-saving switches for one country in 2026–2028, from the official lists and statutes. kind=holidays (uk, us, de, fr): every public holiday of the year with its date and weekday, by region — UK nations (england-and-wales, scotland, northern-ireland; substitute days flagged), US federal (statutory date plus OPM's observed date when it falls on a weekend), German Länder by code or name (nationwide = the nine bundeseinheitlichen Feiertage; partial holidays carry their scope), French metropole or alsace-moselle. kind=tax-year (uk, us, au, in, ca, de, fr, br, pl): the personal tax year's start and end with the periods for 2026–2028 and the statute or official page quoted, plus the government fiscal year where it differs. kind=dst (uk, de, fr, us, au, br): the statutory rule and the computed clocks-forward and clocks-back dates per year, with the states that observe it for Australia and observed:false for Brazil. Country names, UK nations, German Land names (Bavaria, Sachsen) and kind synonyms (bank holidays, financial year, clocks) resolve; no country lists everything covered; unknown countries, regions and years answer covered:false with the nearest matches. Entries that could not be re-verified against an official page carry nonOfficial: true.

Input parameters:

- `country` (string): one of uk, us, de, fr, au, in, ca, br, pl, or a name (United Kingdom, Germany, Bavaria resolves to de with region BY); omit to list
- `kind` (string): holidays | tax-year | dst (synonyms accepted: bank holidays, financial year, daylight saving)
- `region` (string): UK: england-and-wales | scotland | northern-ireland; US: federal; Germany: nationwide or a Land (BY, Bayern, Bavaria, …); France: metropole | alsace-moselle
- `year` (integer): 2026–2028; holidays default to the current year, tax-year and dst to all years covered

### `next_holiday` (~200 tokens)

Next public holiday

The next public holiday strictly after a date (default: today) for uk, us, de, fr, with its name, date, weekday and days until it, the three that follow, and any holiday falling on the date itself; by region as for calendar_facts (UK nations, US federal with OPM's observed date deciding the order, German Länder, French zones). The data runs to the end of 2028; a later date answers covered:false with the last date covered. From the same monthly snapshot of the official lists, with the list's URL as source.

Input parameters:

- `country` (string, required): one of uk, us, de, fr, or a name
- `from` (string): ISO date YYYY-MM-DD; the next holiday is the first one after this day (default: today)
- `region` (string): as for calendar_facts (default: england-and-wales, federal, nationwide, metropole)

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar#diagnostics

## Score history

- 2026-11-05: 33
- 2026-11-04: 33
- 2026-11-03: 33
- 2026-11-02: 33
- 2026-11-01: 33
- 2026-10-31: 83
- 2026-10-30: 83
- 2026-10-29: 82
- 2026-10-28: 82
- 2026-10-27: 81
- 2026-10-26: 81
- 2026-10-25: 80
- 2026-10-24: 80
- 2026-10-23: 79
- 2026-10-22: 79
- 2026-10-21: 78
- 2026-10-20: 78
- 2026-10-19: 77
- 2026-10-18: 77
- 2026-10-17: 76
- 2026-10-16: 76
- 2026-10-15: 76
- 2026-10-14: 76
- 2026-10-13: 75
- 2026-10-12: 75
- 2026-10-10: 74
- 2026-10-09: 73
- 2026-10-06: 72
- 2026-10-04: 71

## Common questions

### What is the io.github.physics-star-cat/databutler-calendar MCP server?

io.github.physics-star-cat/databutler-calendar is an MCP server listed in the public MCP registry as io.github.physics-star-cat/databutler-calendar. Public holidays (UK, US, DE, FR), tax-year dates and DST switches for 2026-2028. This page covers its hosted endpoint (https://databutler.dev/api/mcp/calendar).

### Is the io.github.physics-star-cat/databutler-calendar MCP server safe to use?

io.github.physics-star-cat/databutler-calendar scores 33 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 io.github.physics-star-cat/databutler-calendar MCP server expose?

io.github.physics-star-cat/databutler-calendar exposes 2 tools: calendar_facts, next_holiday. Their descriptions and schemas cost roughly 665 tokens of context every time the server is loaded.

### Does the io.github.physics-star-cat/databutler-calendar MCP server require authentication?

Yes. io.github.physics-star-cat/databutler-calendar 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 io.github.physics-star-cat/databutler-calendar MCP server still maintained?

io.github.physics-star-cat/databutler-calendar is still listed as active in the MCP registry. We last reached this channel on 5 November 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://databutler.dev/api/mcp/calendar
- Repository: https://github.com/physics-star-cat/databutler
- Website: https://databutler.dev/api
- Changelog RSS feed: https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar.xml
- Changelog JSON feed: https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar.json
- HTML version of this page: https://verifymcp.io/servers/physics-star-cat-databutler-calendar/api-mcp-calendar