# VACO Index 30-Day Mortality Calculator (King 2020)

> VACO Index 30-Day Mortality Calculator (King 2020) is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Computes the VACO Index logistic 30-day all-cause mortality probability from age, sex, unadjusted Charlson comorbidity index, and MI/PVD history using King 2020 Supplement S3 coefficients.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/vaco
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vaco-index-30-day-mortality-calculator-king-2020-f2cade22
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8ZRAZW7Dh_T8cj2sfRAGo

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 vaco-index-30-day-mortality-calculator-king-2020-f2cade22
```

Example prompt: Calculate the VACO Index 30-day all-cause mortality probability for a 72-year-old male with an unadjusted Charlson comorbidity index of 6 and a history of myocardial infarction or peripheral vascular disease.

## When to prefer this

Use this endpoint when you need the specific King 2020 VACO Index logistic regression model (Supplement S3 coefficients) for estimating 30-day all-cause mortality in veteran or similar populations. Prefer this over generic mortality calculators when the caller has already assigned a Charlson comorbidity index, sex, and MI/PVD status externally and needs the published VACO Index formula — not VACS Index 1.0 or 2.0 variants.

## Known failure modes

- Age out of range (< 20 or > 120) returns a validation error
- Invalid sex enum value (not 'male' or 'female') returns a bad request error
- CCI integer outside 0-37 returns a validation error
- Missing required query parameters (age, sex, cci, mi_pvd) returns a 400 error
- Payment not included or insufficient USDC (x402 protocol) returns a 402 Payment Required

## How this service works

King 2020 VACO Index logistic 30-day all-cause mortality from age, sex, caller-assigned unadjusted Charlson comorbidity index, and history of myocardial infarction or peripheral vascular disease. Supplement S3 coefficients. Age 85 or older uses the published combined CCI term. Not VACS Index 1.0 or 2.0, not a diagnosis, and not a treatment order.

## Output

Returns a 30-day all-cause mortality probability (as a logistic model output) computed from the King 2020 VACO Index Supplement S3 coefficients, using the caller-supplied age band, sex, unadjusted CCI category, and MI/PVD flag. For patients aged 85 or older, the combined CCI term is applied automatically regardless of the integer CCI supplied.

## 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": [
      "age",
      "sex",
      "cci",
      "mi_pvd"
     ],
     "properties": {
      "age": {
       "type": "integer",
       "description": "Age in years (integer 20-120). King 2020 S3 bands: 20-50 (ages 20-49), 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-89, ge90. Age 50 uses 50-54. Age 85-89 keeps the 80-89 age term and the age>=85 CCI term."
      },
      "cci": {
       "type": "integer",
       "description": "Unadjusted Charlson comorbidity index as assigned by the caller (integer 0-37). King 2020 S3: 0 (reference), 1-3, 4-5, 6-9, ge10 when age<85. Age 85 or older uses the published combined CCI term regardless of this integer. magent does not assign Charlson diagnoses."
      },
      "sex": {
       "enum": [
        "female",
        "male"
       ],
       "type": "string",
       "description": "Sex as assigned by the caller. female is the S3 reference (0). male adds 0.322291449. magent does not assign sex."
      },
      "mi_pvd": {
       "type": "boolean",
       "description": "History of myocardial infarction or peripheral vascular disease as assigned by the caller (true or false). false is the S3 reference (0). true adds 0.267265312."
      }
     }
    }
   },
   "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/vaco-index-30-day-mortality-calculator-king-2020-f2cade22/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)