# HE-MACS ACS Probability Calculator (Alghamdi 2019)

> HE-MACS ACS Probability Calculator (Alghamdi 2019) 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).

Calculates the probability of acute coronary syndrome (ACS) using the HE-MACS model based on age, sex, and six clinical observations.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/he_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/he-macs-acs-probability-calculator-alghamdi-2019-49384206
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uxtFJt4eukVzlhzlNeXrO

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 he-macs-acs-probability-calculator-alghamdi-2019-49384206
```

Example prompt: Run the HE-MACS ACS probability score for a 58-year-old male who has observed sweating, acute ECG ischaemia present, no pain radiation to the right arm or shoulder, no vomiting, no hypotension, and is a current smoker.

## When to prefer this

Choose this endpoint when you need to apply the specific Alghamdi 2019 HE-MACS model for ACS probability estimation using only clinical signs (no biomarkers required). Prefer this over MACS (Body 2014) or T-MACS when biomarker data is unavailable or when replicating the HE-MACS study methodology. It is not a substitute for HEART score, TIMI, or GRACE, and does not replace clinical judgment or ECG interpretation.

## Known failure modes

- Missing required query parameter returns an error (e.g. omitting age or sex)
- Age value outside the clamped range (18–100) may be silently clamped or return a validation error
- Invalid sex value (not 'male' or 'female') returns a validation error
- Boolean fields passed as strings instead of true/false booleans may fail schema validation
- Network or payment (x402) failure results in no response

## How this service works

Alghamdi 2019 HE-MACS ACS probability from age, sex, caller-assigned observed sweating, acute ECG ischaemia, right-arm or shoulder radiation, vomiting, hypotension (SBP <100), and current smoking. Table 2 printed coefficients. Returns probability only; four-group ROC thresholds are in that paper's supplement and are not restated here. magent does not interpret ECG or take a history. Not MACS (Body 2014 biomarkers) or T-MACS. Not a diagnosis.

## Output

Returns a single numeric probability (0–1) representing the likelihood of acute coronary syndrome (ACS) as computed by the Alghamdi 2019 HE-MACS logistic regression model using the Table 2 coefficients. Does not include ROC-based risk group thresholds, ECG interpretation, or a clinical 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": [
      "age",
      "sex",
      "sweating_observed",
      "acute_ecg_ischaemia",
      "pain_radiation_right_arm_or_shoulder",
      "vomiting",
      "hypotension",
      "current_smoker"
     ],
     "properties": {
      "age": {
       "type": "number",
       "description": "Age in years as a continuous linear predictor (g; 18-100, implementation clamp). Alghamdi 2019 Table 2. magent does not read an identity document."
      },
      "sex": {
       "enum": [
        "female",
        "male"
       ],
       "type": "string",
       "description": "Sex used as h in Alghamdi 2019 Table 2 (male = 1, female = 0). male or female, case-insensitive. magent does not examine the patient."
      },
      "vomiting": {
       "type": "boolean",
       "description": "Vomiting associated with the pain as assigned by the caller (d; Alghamdi 2019). true or false."
      },
      "hypotension": {
       "type": "boolean",
       "description": "Hypotension as assigned by the caller (e): systolic BP <100 mm Hg (Alghamdi 2019, dichotomised as in that paper). true or false."
      },
      "current_smoker": {
       "type": "boolean",
       "description": "Current tobacco smoker as assigned by the caller (f; Alghamdi 2019). true or false. magent does not take a smoking history."
      },
      "sweating_observed": {
       "type": "boolean",
       "description": "Sweating observed by the treating clinician as assigned by the caller (a; 1 if true, 0 if false). true or false. magent does not examine the patient."
      },
      "acute_ecg_ischaemia": {
       "type": "boolean",
       "description": "Caller-assigned acute ECG ischaemia as used in Alghamdi 2019 (b): ST-deviation or abnormal T inversion (1 if true, 0 if false). magent does not interpret an ECG."
      },
      "pain_radiation_right_arm_or_shoulder": {
       "type": "boolean",
       "description": "Pain radiating to the right arm or shou
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/he-macs-acs-probability-calculator-alghamdi-2019-49384206/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)