# MACS ACS Probability Calculator (Body 2014)

> MACS ACS Probability Calculator (Body 2014) 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 Manchester Acute Coronary Syndromes (MACS) probability score and risk band for acute coronary syndrome using ECG findings, clinical signs, and biomarkers (hs-cTnT and H-FABP).

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/macs
- 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/macs-acs-probability-calculator-body-2014-02a8f9c2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YJBmjZrZkU2Vf-6cxB22e

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 macs-acs-probability-calculator-body-2014-02a8f9c2
```

Example prompt: Calculate the MACS ACS probability for a patient with ECG ischaemia present, worsening angina, no right-arm radiation, vomiting, sweating observed, no hypotension, hs-cTnT of 18 ng/L, and H-FABP of 6.2 ng/mL.

## When to prefer this

Use this endpoint when you need to apply the specific Body 2014 MACS decision rule using Roche hs-cTnT and ELISA H-FABP — it is not HEART, EDACS, or T-MACS. Prefer this when your clinical workflow explicitly calls for the MACS algorithm with H-FABP as a co-predictor alongside troponin, particularly in settings where ELISA H-FABP results are available.

## Known failure modes

- Missing required query parameters returns a validation error
- Non-boolean values for binary clinical flags cause a schema error
- Out-of-range biomarker values are clamped (hs-cTnT 0–100000 ng/L, H-FABP 0–200 ng/mL) but extreme outliers may reduce clinical reliability
- Payment failure (402) if x402 payment is not properly handled
- Network timeout on the GET request

## How this service works

Body 2014 MACS ACS probability from caller-assigned ECG ischaemia, worsening angina, right-arm radiation, vomiting, observed sweating, hypotension (SBP <100), Roche hs-cTnT ng/L, and ELISA H-FABP ng/mL. Table 2 rounded coefficients. Bands p<0.02 very_low, 0.02<=p<0.05 low, 0.05<=p<0.95 moderate, p>=0.95 high. magent does not interpret ECG or assay biomarkers. Not T-MACS, HEART, or EDACS. Not a diagnosis.

## Output

Returns the MACS ACS probability (continuous 0–1 value computed from Table 2 logistic coefficients of Body 2014) and a categorical risk band: very_low (p<0.02), low (0.02≤p<0.05), moderate (0.05≤p<0.95), or high (p≥0.95). Does not provide a diagnosis.

## 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": [
      "ecg_ischaemia",
      "worsening_angina",
      "pain_radiation_right_arm_or_shoulder",
      "vomiting",
      "sweating_observed",
      "hypotension",
      "hs_ctnt_ng_l",
      "h_fabp_ng_ml"
     ],
     "properties": {
      "vomiting": {
       "type": "boolean",
       "description": "Vomiting in association with the presenting symptoms as assigned by the caller (e; Body 2014). true or false."
      },
      "hypotension": {
       "type": "boolean",
       "description": "Hypotension as assigned by the caller (f): systolic BP <100 mm Hg on arrival (Body 2014, dichotomised as in that paper). true or false."
      },
      "h_fabp_ng_ml": {
       "type": "number",
       "description": "Heart-type fatty acid-binding protein by ELISA in ng/mL as in Body 2014 (b; 0-200, implementation clamp). Continuous linear predictor. magent does not convert units, assay H-FABP, or apply the later immunoturbidimetric transform."
      },
      "hs_ctnt_ng_l": {
       "type": "number",
       "description": "Roche Diagnostics Elecsys high-sensitivity cardiac troponin T on arrival in ng/L (a; 0-100000, implementation clamp). Continuous linear predictor in Body 2014 Table 2. magent does not convert units or assay troponin."
      },
      "ecg_ischaemia": {
       "type": "boolean",
       "description": "Caller-assigned ECG ischaemia as used in Body 2014 (c; 1 if true, 0 if false). magent does not interpret an ECG."
      },
      "worsening_angina": {
       "type": "boolean",
       "description": "Worsening or crescendo angina as assigned by the caller (g): anginal pain with increasing frequency, occurring with less exertion, or becoming more prolonged (Body 2014). true or false."
      },
      "sweating_observed": {
       "type": "boolean",
       "description": "Sweating observed by the treating clinician as assigned by the caller (d; Body 2014). true or false. magent does not examine th
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/macs-acs-probability-calculator-body-2014-02a8f9c2/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)