magent

Deterministic published-formula arithmetic plus ICD-10-CM, RxNorm, and LOINC. Pay in USDC on Base via x402.

Tradingofflineeip155:8453Exactvia cdp
Pecarn-febrileFebrile-infantEmergencySbiCalculator
Calls · 30d
2→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 13 snapshots so far.
$13.75
Verified settled volume
2,750 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0050
Listed price
As published in the catalog. Always read the live 402 before paying.
2
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-08-31 13:22Z
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x836Be278f1739fB4308091cD1852F7971Bc19Ee2

The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider

The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "error": "PAYMENT-SIGNATURE header is required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2",
        "paymentFlow": "upfront",
        "resourceUrl": "https://api.magentlab.com/api/calc/pecarn_febrile",
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
      "amount": "5000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 600
    },
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2",
        "withdrawDelay": 86400,
        "receiverAuthorizer": "0x3721824a31197dcDD2984cF43b92B6cc8A87c0Fb",
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
      "amount": "5000",
      "scheme": "batch-settlement",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 600
    }
  ],
  "resource": {
    "url": "https://api.magentlab.com/api/calc/pecarn_febrile",
    "tags": [
      "pecarn-febrile",
      "febrile-infant",
      "emergency",
      "sbi",
      "calculator"
    ],
    "mimeType": "application/json",
    "description": "Kuppermann 2019 PECARN prediction rule for febrile infants 60 days and younger. Low-risk only if all three hold: caller-assigned negative urinalysis, ANC 4090/uL or less, and serum procalcitonin 1.71 ng/mL or less. Age 0-60 pins the published population and is not a tree variable. Returns low_risk. magent does not assay UA, ANC, or PCT. Not Rochester, Boston, Philadelphia, Step-by-Step, later AAP/PECARN cutoffs, or pecarn-head. Not a medical device and not a discharge or LP order.",
    "serviceName": "magent"
  },
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "type": "http",
          "method": "GET",
          "queryParams": {
            "age_days": 36,
            "pct_ng_ml": 0.5,
            "anc_per_ul": 3000,
            "negative_urinalysis": true
          }
        },
        "output": {
          "type": "json",
          "example": {
            "formula": "pecarn_febrile",
            "age_days": 36,
            "citation": {
              "id": "kuppermann-2019",
              "doi": "10.1001/jamapediatrics.2018.5501",
              "pmid": "30776077",
              "title": "A Clinical Prediction Rule to Identify Febrile Infants 60 Days and Younger at Low Risk for Serious Bacterial Infections.",
              "source": "JAMA Pediatr. 2019;173(4):342-351",
              "authors": "Kuppermann N, Dayan PS, Levine DA, et al."
            },
            "criteria": [
              {
                "met": true,
                "factor": "negative_urinalysis"
              },
              {
                "met": true,
                "value": 3000,
                "factor": "anc_le_4090"
              },
              {
                "met": true,
                "value": 0.5,
                "factor": "pct_le_1_71"
              }
            ],
            "low_risk": true,
            "pct_ng_ml": 0.5,
            "anc_per_ul": 3000,
            "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_expression": "low_risk iff negative_urinalysis and anc_per_ul <= 4090 and pct_ng_ml <= 1.71; age_days 0-60 pins the published population and is not a tree variable (Kuppermann 2019)"
          }
        },
        "iconUrl": "https://api.magentlab.com/favicon.ico"
      },
      "schema": {
        "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_days",
                  "negative_urinalysis",
                  "anc_per_ul",
                  "pct_ng_ml"
                ],
                "properties": {
                  "age_days": {
                    "type": "integer",
                    "description": "Chronological age in days (integer 0-60). Kuppermann 2019 studied febrile infants 60 days and younger. Age pins the published population and is not a tree variable; age 0 and age 60 can both be low-risk when the three laboratory criteria hold."
                  },
                  "pct_ng_ml": {
                    "type": "number",
                    "description": "Serum procalcitonin in ng/mL. Range 0.01-100. Low-risk requires 1.71 ng/mL or less (1.71 meets; 1.72 does not). magent does not assay procalcitonin."
                  },
                  "anc_per_ul": {
                    "type": "number",
                    "description": "Absolute neutrophil count in cells/µL. Range 0-100000. Low-risk requires ANC 4090/µL or less (4090 meets; 4091 does not). magent does not assay ANC."
                  },
                  "negative_urinalysis": {
                    "type": "boolean",
                    "description": "Caller-assigned negative urinalysis as used in Kuppermann 2019. true means the UA is negative. true or false. magent does not assay UA."
                  }
                }
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string"
              },
              "example": {
                "type": "object"
              }
            }
          }
        }
      }
    }
  },
  "x402Version": 2
}

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

0.005USDC≈ $0.005 USD
on Base · exact scheme

Pay 0.005 USDC on Base to 0x836B…19Ee2. The signed payment is good for 10 minutes.

USD Coin contract
0x8335…02913
Payment window
10 minutes
As published
5000 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2",
      "paymentFlow": "upfront",
      "resourceUrl": "https://api.magentlab.com/api/calc/pecarn_febrile",
      "assetTransferMethod": "eip3009"
    },
    "payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
    "amount": "5000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 600
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "items": [
            {
              "age_days": 36,
              "pct_ng_ml": 0.5,
              "anc_per_ul": 3000,
              "negative_urinalysis": true
            },
            {
              "age_days": 36,
              "pct_ng_ml": 0.5,
              "anc_per_ul": 3000,
              "negative_urinalysis": true
            }
          ]
        },
        "type": "http",
        "method": "POST"
      },
      "output": {
        "type": "json",
        "example": {
          "path": "/api/calc/pecarn_febrile",
          "count": 2,
          "items": [
            {
              "formula": "pecarn_febrile",
              "age_days": 36,
              "citation": {
                "id": "kuppermann-2019",
                "doi": "10.1001/jamapediatrics.2018.5501",
                "pmid": "30776077",
                "title": "A Clinical Prediction Rule to Identify Febrile Infants 60 Days and Younger at Low Risk for Serious Bacterial Infections.",
                "source": "JAMA Pediatr. 2019;173(4):342-351",
                "authors": "Kuppermann N, Dayan PS, Levine DA, et al."
              },
              "criteria": [
                {
                  "met": true,
                  "factor": "negative_urinalysis"
                },
                {
                  "met": true,
                  "value": 3000,
                  "factor": "anc_le_4090"
                },
                {
                  "met": true,
                  "value": 0.5,
                  "factor": "pct_le_1_71"
                }
              ],
              "low_risk": true,
              "pct_ng_ml": 0.5,
              "anc_per_ul": 3000,
              "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_expression": "low_risk iff negative_urinalysis and anc_per_ul <= 4090 and pct_ng_ml <= 1.71; age_days 0-60 pins the published population and is not a tree variable (Kuppermann 2019)"
            },
            {
              "formula": "pecarn_febrile",
              "age_days": 36,
              "citation": {
                "id": "kuppermann-2019",
                "doi": "10.1001/jamapediatrics.2018.5501",
                "pmid": "30776077",
                "title": "A Clinical Prediction Rule to Identify Febrile Infants 60 Days and Younger at Low Risk for Serious Bacterial Infections.",
                "source": "JAMA Pediatr. 2019;173(4):342-351",
                "authors": "Kuppermann N, Dayan PS, Levine DA, et al."
              },
              "criteria": [
                {
                  "met": true,
                  "factor": "negative_urinalysis"
                },
                {
                  "met": true,
                  "value": 3000,
                  "factor": "anc_le_4090"
                },
                {
                  "met": true,
                  "value": 0.5,
                  "factor": "pct_le_1_71"
                }
              ],
              "low_risk": true,
              "pct_ng_ml": 0.5,
              "anc_per_ul": 3000,
              "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_expression": "low_risk iff negative_urinalysis and anc_per_ul <= 4090 and pct_ng_ml <= 1.71; age_days 0-60 pins the published population and is not a tree variable (Kuppermann 2019)"
            }
          ]
        }
      },
      "iconUrl": "https://api.magentlab.com/favicon.ico"
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "body": {
              "type": "object",
              "required": [
                "items"
              ],
              "properties": {
                "items": {
                  "type": "array",
                  "items": {
                    "type": "object",
                    "required": [
                      "age_days",
                      "negative_urinalysis",
                      "anc_per_ul",
                      "pct_ng_ml"
                    ],
                    "properties": {
                      "age_days": {
                        "type": "integer",
                        "description": "Chronological age in days (integer 0-60). Kuppermann 2019 studied febrile infants 60 days and younger. Age pins the published population and is not a tree variable; age 0 and age 60 can both be low-risk when the three laboratory criteria hold."
                      },
                      "pct_ng_ml": {
                        "type": "number",
                        "description": "Serum procalcitonin in ng/mL. Range 0.01-100. Low-risk requires 1.71 ng/mL or less (1.71 meets; 1.72 does not). magent does not assay procalcitonin."
                      },
                      "anc_per_ul": {
                        "type": "number",
                        "description": "Absolute neutrophil count in cells/µL. Range 0-100000. Low-risk requires ANC 4090/µL or less (4090 meets; 4091 does not). magent does not assay ANC."
                      },
                      "negative_urinalysis": {
                        "type": "boolean",
                        "description": "Caller-assigned negative urinalysis as used in Kuppermann 2019. true means the UA is negative. true or false. magent does not assay UA."
                      }
                    }
                  },
                  "maxItems": 25,
                  "minItems": 1
                }
              },
              "additionalProperties": false
            },
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "type": "string",
              "const": "POST"
            },
            "headers": {
              "type": "object",
              "additionalProperties": {
                "type": "string"
              }
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object"
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-08-31 13:22Z
Last indexed by Roundhouse
2026-09-07 06:20Z
Last enriched (probe, favicon, geo)
2026-09-13 09:45Z
x402 version
2
Max timeout
600s
Liveness probe
HTTP 0
Report

Hand this page to an agent

Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.

GET api.roundhouseai.io/v0/endpoints

This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 13 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Open skill.md
Show the prompt
Using Roundhouse, look up the x402 service magent and tell me whether it is
worth paying: what a call costs, whether the endpoint answered when last probed, and what
its payment record actually shows.

curl -s 'https://api.roundhouseai.io/v0/endpoints?q=magent'
curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>'

Then call it: read the price from the live 402 at https://api.magentlab.com/api/calc/pecarn_febrile, never from
a cached figure, and pay with an x402 client.

The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except
/v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402,
or use an organization key from https://roundhouseai.io/dashboard/team.

If you do not have Roundhouse tools or skills installed, read
https://roundhouseai.io/skill.md first — it is the whole procedure.