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D Fetcher

by dfetcher.com · remote · no sign-in to list tools · v1.0.0 · published by com.dfetcher

Vitamin D synthesis calculator: sun position, UV, IU/min, time to dose, sunburn risk, daily window.

Changes · 2
CompareRegistry entry

3 tools: 2 change things and 1 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 vitamin-d https://dfetcher.com/mcp

Tools

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

3 tools

Changes things 2Claude Code: ask
  • calculateCalculate vitamin D synthesis at a given location and time.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Calculate vitamin D synthesis at a given location and time. Returns sun position, UV index, IU/min, minutes to reach the target dose, MED (sunburn threshold), the peak window, and optional 15-min day / monthly year curves. UV index uses a live satellite-driven forecast where available, with a clear-sky fallback.
  • geocodeTurn a place name, postal code, or "code, CC" string into { lat, lon, label }.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Turn a place name, postal code, or "code, CC" string into { lat, lon, label }. Auto-detects US/CA/GB/NL/JP/BR postal patterns; ambiguous digit-only codes default to US unless the caller appends a country code (e.g. "10115, DE"). Falls back to Open-Meteo place-name search for everything else.
Only reads 1Claude Code: allow
  • describe_skin_typesReturns the six Fitzpatrick skin types with sun-reactivity behavior and descriptive ancestry hints.No findings

    Why it is in this group

    • The name "describe_skin_types" says "describe": a word for reading.
    Description, as the server wrote it
    Returns the six Fitzpatrick skin types with sun-reactivity behavior and descriptive ancestry hints. Call this when the user's skin type is unknown so you can pick the closest match before calling calculate.

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 1.0.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http vitamin-d https://dfetcher.com/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__vitamin-d__describe_skin_types"
    ],
    "ask": [
      "mcp__vitamin-d__calculate",
      "mcp__vitamin-d__geocode"
    ],
    "deny": []
  }
}

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 vitamin-d. Review it before you use it.