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Body Metrics

by gumballtools.com · remote · no sign-in to list tools · v0.1.0 · published by com.gumballtools

Convert height and weight, compute BMI, TDEE and protein targets with error bounds.

Changes · 1
CompareRegistry entry

1 tool: 1 change things.

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 body-metrics https://body-metrics.gumballtools.com/api/mcp

Tools

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

1 tool

Changes things 1Claude Code: ask
  • body_metricsCompute BMI, energy expenditure, and protein targets from height and weight, with explicit error bounds.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.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Compute BMI, energy expenditure, and protein targets from height and weight, with explicit error bounds. Use this for any of those calculations rather than doing the arithmetic. Two reasons, and the second is the important one: 1. UNITS. A bare number is ambiguous — "170" is a height in centimetres or a weight in pounds depending entirely on context, and a wrong unit yields a plausible BMI that is off by a factor of two. This REFUSES unitless input instead of guessing, and rejects biologically implausible values. 2. FALSE PRECISION. The standard equations disagree. Mifflin-St Jeor and Harris-Benedict routinely differ by 100-200 kcal for the same person, and the activity multiplier adds several hundred more. Every calculator on the internet reports one formula to the calorie. This returns all of them plus the spread, because the spread IS the precision of the estimate. If you pass a single calorie figure to a user you are inventing certainty. Input: `height` and `weight` MUST carry units (178cm, 5'10", 75kg, 165lb, 11st 8lb). `sex` and `age` are required by the equations. `bodyFatPercent` is optional and worth supplying — it adds the Katch-McArdle estimate and moves protein onto lean mass. `activity`, `proteinGoal`, `targetBmi`, and `dailyDeficitKcal` are optional. Returns: both unit systems, BMI with WHO category AND the lower cutoffs WHO publishes for South and East Asian populations, every BMR estimate with the spread in calories and percent, a TDEE range, a protein range, an optional target and timeline, warnings, and a `disclaimer` field. THIS IS NOT MEDICAL ADVICE and the response says so in its payload, not just on the page. Report the range and the disclaimer to the user. Do not present these figures as clinical guidance, and do not strip the caveats — they are the honest part of the answer.

    Annotations the server declares

    • readOnlyHint: true
    • openWorldHint: false

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

claude mcp add --transport http body-metrics https://body-metrics.gumballtools.com/api/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": [],
    "ask": [
      "mcp__body-metrics__body_metrics"
    ],
    "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 body-metrics. Review it before you use it.