# METS-IR Calculator (Bello-Chavolla 2018)

> METS-IR Calculator (Bello-Chavolla 2018) is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-13).

Computes the Metabolic Score for Insulin Resistance (METS-IR) from fasting glucose, triglycerides, HDL cholesterol, and BMI, and flags the highest T2D-risk quartile (>50.39).

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/mets_ir
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mets-ir-calculator-bello-chavolla-2018-5b3a2331
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2gQPqWOQ4aj5oY_H_POAK

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability mets-ir-calculator-bello-chavolla-2018-5b3a2331
```

Example prompt: Calculate the METS-IR score for a patient with a fasting glucose of 95 mg/dL, triglycerides of 180 mg/dL, HDL of 42 mg/dL, and a BMI of 28.5 — and let me know if they fall in the highest T2D-risk quartile.

## When to prefer this

Use this endpoint when you need a non-insulin-based surrogate index of insulin resistance derived from a standard lipid panel and BMI, following the Bello-Chavolla 2018 derivation. Prefer it over HOMA-IR/HOMA2 when fasting insulin is unavailable. It is specifically useful for epidemiological screening or risk stratification using the >50.39 highest-quartile T2D cutoff from the original derivation study. Do not use it as a diabetes diagnosis or treatment threshold.

## Known failure modes

- Missing required BMI parameter returns validation error
- Supplying both mg/dL and mmol/L for the same analyte returns a conflict error
- Values outside accepted ranges (e.g. BMI <10 or >80, glucose <50 or >1000 mg/dL) return a range validation error
- HDL value of zero or near-zero causes a logarithm domain error
- Missing all three lipid/glucose inputs returns an incomplete input error

## How this service works

Bello-Chavolla 2018 METS-IR: ln(2×glucose_mg_dl + triglycerides_mg_dl)×BMI / ln(HDL_mg_dl), natural log, two decimals. Supply glucose, triglycerides, and HDL each as exactly one of mg/dL or mmol/L (glucose ×18, TG ×88.57, HDL ×38.67). BMI is caller-supplied (10–80). highest_quartile_t2d is true only when METS-IR > 50.39 (derivation highest T2D-risk quartile). Not a diabetes diagnosis, not HOMA-IR/HOMA2, and not a treatment threshold.

## Output

Returns the METS-IR score rounded to two decimal places, computed as ln(2×glucose_mg_dL + triglycerides_mg_dL) × BMI / ln(HDL_mg_dL), along with a boolean flag 'highest_quartile_t2d' that is true when the score exceeds 50.39 (the derivation cohort's highest T2D-risk quartile threshold).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "bmi_kg_m2"
     ],
     "properties": {
      "bmi_kg_m2": {
       "type": "number",
       "description": "Body-mass index in kg/m^2 (10-80). Caller-supplied; magent does not compute BMI."
      },
      "hdl_mg_dl": {
       "type": "number",
       "description": "HDL cholesterol in mg/dL (5-150). Provide this or hdl_mmol_l, not both. Used in the natural-log term."
      },
      "hdl_mmol_l": {
       "type": "number",
       "description": "HDL cholesterol in mmol/L (0.1-3.9). Converted as mg/dL = mmol/L * 38.67. Provide this or hdl_mg_dl, not both."
      },
      "glucose_mg_dl": {
       "type": "number",
       "description": "Fasting plasma glucose in mg/dL (50-1000). Provide this or glucose_mmol_l, not both."
      },
      "glucose_mmol_l": {
       "type": "number",
       "description": "Fasting plasma glucose in mmol/L (2.8-55.5). Converted as mg/dL = mmol/L * 18. Provide this or glucose_mg_dl, not both."
      },
      "triglycerides_mg_dl": {
       "type": "number",
       "description": "Triglycerides in mg/dL (10-2000). Provide this or triglycerides_mmol_l, not both."
      },
      "triglycerides_mmol_l": {
       "type": "number",
       "description": "Triglycerides in mmol/L (0.11-22.6). Converted as mg/dL = mmol/L * 88.57. Provide this or triglycerides_mg_dl, not both."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mets-ir-calculator-bello-chavolla-2018-5b3a2331/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)