# io.github.hebcal/hebcal (remote · www.hebcal.com)

Model Context Protocol extension for Hebrew calendar

- Trust score: 67/100 (medium)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- remote · `www.hebcal.com`: 67/100 (this document), [markdown](https://verifymcp.io/servers/hebcal-hebcal/www.md), [page](https://verifymcp.io/servers/hebcal-hebcal/www)
- npm · `@hebcal/mcp`: 35/100, [markdown](https://verifymcp.io/servers/hebcal-hebcal/hebcal-mcp.md), [page](https://verifymcp.io/servers/hebcal-hebcal/hebcal-mcp)

## Channel facts

- Endpoint: `https://www.hebcal.com/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.9.9`

## 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 2026-08-03.

- **Endpoint Security**: 57/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 7 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - 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**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 77/100
  - AI-judged instruction clarity (excellent).
  - Tool/resource definitions use about 453 tokens (~64/item across 7 items; 7 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add --transport http hebcal-hebcal https://www.hebcal.com/mcp
```

### Codex

```toml
[mcp_servers.hebcal-hebcal]
url = "https://www.hebcal.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "hebcal-hebcal": {
      "type": "remote",
      "url": "https://www.hebcal.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add hebcal-hebcal --url https://www.hebcal.com/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  hebcal-hebcal:
    url: "https://www.hebcal.com/mcp"
```

### Other

```json
{
  "mcpServers": {
    "hebcal-hebcal": {
      "type": "http",
      "url": "https://www.hebcal.com/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.

### 2026-08-02 (score 67, +1)

No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-31 (score 66, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 66, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-29 (score 66, +1)

No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-28 (score 65, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-27 (score 64, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-26 (score 64)

First indexed and scored.

## MCP tools (7)

### `convert-gregorian-to-hebrew` (~47 tokens)

Converts a Gregorian (civil) date to a Hebrew date (Jewish calendar)

Input parameters:

- `date` (string, required): Gregorian date (in yyyy-MM-dd format) to convert

### `convert-hebrew-to-gregorian` (~66 tokens)

Converts a Hebrew date to a Gregorian (civil) date

Input parameters:

- `day` (integer, required): Hebrew day of month
- `month` (string, required): Hebrew month name transliterated, like Elul or Tishrei
- `year` (integer, required): Hebrew year

### `yahrzeit` (~65 tokens)

Calculates the Yahrzeit, the anniversary of the day of death of a loved one, according to the Hebrew calendar for a specified date

Input parameters:

- `afterSunset` (boolean, required): after sunset
- `date` (string, required): Gregorian date of death (in yyyy-MM-dd format)

### `torah-portion` (~61 tokens)

Calculates the weekly Torah portion (also called parashat haShavua) for a specified date

Input parameters:

- `date` (string, required): Gregorian date in yyyy-MM-dd format
- `il` (boolean, required): True if in Israel, false for Diaspora

### `jewish-holidays-year` (~34 tokens)

Calculates a list of all Jewish holidays during a Gregorian (civil) year

Input parameters:

- `year` (integer, required): Gregorian year

### `daf-yomi` (~42 tokens)

Calculates the Daf Yomi (Babylonian Talmud) learning for a specified date

Input parameters:

- `date` (string, required): Gregorian date in yyyy-MM-dd format

### `shabbat-times` (~138 tokens)

Generates Shabbat and holiday candle-lighting and Havdalah times for a given location and date range

Input parameters:

- `endDate` (string, required): End date in yyyy-MM-dd format
- `latitude` (number, required): Latitude as decimal, valid range -90 to +90 (e.g. 41.85003)
- `longitude` (number, required): Longitude as decimal, valid range -180 to +180 (e.g. -87.65005)
- `startDate` (string, required): Start date in yyyy-MM-dd format
- `tzid` (string, required): Olson timezone ID (e.g. "America/Chicago", "Europe/Moscow")

## Diagnostics

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

## Score history

- 2026-08-03: 67
- 2026-08-02: 67
- 2026-08-01: 66
- 2026-07-31: 66
- 2026-07-30: 66
- 2026-07-29: 66
- 2026-07-28: 65
- 2026-07-27: 64
- 2026-07-26: 64

## Links

- Remote endpoint: https://www.hebcal.com/mcp
- Repository: https://github.com/hebcal/hebcal-mcp
- Changelog RSS feed: https://verifymcp.io/servers/hebcal-hebcal/www/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/hebcal-hebcal/www/changelog.json
- HTML version of this page: https://verifymcp.io/servers/hebcal-hebcal/www