Agent Service · x402 · early usage

2013 ACCF/AHA heart-failure stages (Yancy) from four caller flags: high risk for HF, st…

by api.magentlab.com · discovered, not yet claimed by its owner · updated 2026-10-12

30d calls5

30d payers2

MethodPOST

Outputjson

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

2013 ACCF/AHA heart-failure stages (Yancy) from four caller flags: high risk for HF, structural heart disease, prior or current HF symptoms, and refractory specialized care. Returns hf_stage A, B, C, D, or not_staged. Progressive and inviolate: D first, then C, B, A, else not_staged. Not NYHA class and not a diagnosis. magent does not examine the patient or read an echocardiogram.

Tags: acc-aha-hf · heart-failure · hemodynamics · staging · calculator · bazaar

Call contract

Method: POST
Input: HTTP request
Output: json
Last paid call: 2026-10-12

Input example from Bazaar metadata

{
  "items": [
    {
      "hf_symptoms_prior_or_current": false,
      "high_risk_for_hf": false,
      "refractory_hf_specialized": false,
      "structural_heart_disease": false
    },
    {
      "hf_symptoms_prior_or_current": false,
      "high_risk_for_hf": false,
      "refractory_hf_specialized": false,
      "structural_heart_disease": false
    }
  ]
}

Output example

{
  "count": 2,
  "items": [
    {
      "citation": {
        "authors": "Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE Jr, Drazner MH, Fonarow GC, Geraci SA, Horwich T, Januzzi JL, Johnson MR, Kasper EK, Levy WC, Masoudi FA, McBride PE, McMurray JJV, Mitchell JE, Peterson PN, Riegel B, Sam F, Stevenson LW, Tang WHW, Tsai EJ, Wilkoff BL",
        "doi": "10.1161/CIR.0b013e31829e8776",
        "id": "yancy-2013",
        "pmid": "23741058",
        "source": "Circulation. 2013;128(16):e240-e327",
        "title": "2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines"
      },
      "components": [
        {
          "factor": "high_risk_for_hf",
          "met": false
        },
        {
          "factor": "structural_heart_disease",
          "met": false
        },
        {
          "factor": "hf_symptoms_prior_or_current",
          "met": false
        },
        {
          "factor": "refractory_hf_specialized",
          "met": false
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "formula": "acc_aha_hf",
      "formula_expression": "hf_stage D if refractory_hf_specialized; else C if structural_heart_disease and hf_symptoms_prior_or_current; else B if structural_heart_disease and not hf_symptoms_prior_or_current; else A if high_risk_for_hf and not structural_heart_disease and not hf_symptoms_prior_or_current; else not_staged (Yancy 2013 ACCF/AHA stages, progressive/inviolate). Not NYHA class",
      "hf_stage": "not_staged",
      "hf_symptoms_prior_or_current": false,
      "high_risk_for_hf": false,
      "refractory_hf_specialized": false,
      "structural_heart_disease": false
    },
    {
      "citation": {
        "authors": "Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE Jr, Drazner MH, Fonarow GC, Geraci SA, Horwich T, Januzzi JL, Johnson MR, Kasper EK, Levy WC, Masoudi FA, McBride PE, McMurray JJV, Mitchell JE, Peterson PN, Riegel B, Sam F, Stevenson LW, Tang WHW, Tsai EJ, Wilkoff BL",
        "doi": "10.1161/CIR.0b013e31829e8776",
        "id": "yancy-2013",
        "pmid": "23741058",
        "source": "Circulation. 2013;128(16):e240-e327",
        "title": "2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines"
      },
      "components": [
        {
          "factor": "high_risk_for_hf",
          "met": false
        },
        {
          "factor": "structural_heart_disease",
          "met": false
        },
        {
          "factor": "hf_symptoms_prior_or_current",
          "met": false
        },
        {
          "factor": "refractory_hf_specialized",
          "met": false
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "formula": "acc_aha_hf",
      "formula_expression": "hf_stage D if refractory_hf_specialized; else C if structural_heart_disease and hf_symptoms_prior_or_current; else B if structural_heart_disease and not hf_symptoms_prior_or_current; else A if high_risk_for_hf and not structural_heart_disease and not hf_symptoms_prior_or_current; else not_staged (Yancy 2013 ACCF/AHA stages, progressive/inviolate). Not NYHA class",
      "hf_stage": "not_staged",
      "hf_symptoms_prior_or_current": false,
      "high_risk_for_hf": false,
      "refractory_hf_specialized": false,
      "structural_heart_disease": false
    }
  ],
  "path": "/api/calc/acc_aha_hf"
}

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/39325.json for the price and payment options.
Pay. Call GET https://api.magentlab.com/api/calc/acc_aha_hf. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.005 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base
Demand: 5 calls · 2 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.005	0x836Be278f1739fB4308091cD1852F7971Bc19Ee2	600s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 600
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "example": {},
  "type": "string"
}

Examples

curl

curl "https://api.magentlab.com/api/calc/acc_aha_hf"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://api.magentlab.com/api/calc/acc_aha_hf");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://api.magentlab.com/api/calc/acc_aha_hf")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: api.magentlab.com
Endpoint: https://api.magentlab.com/api/calc/acc_aha_hf
Machine-readable: /resources/39325.json