magent
Eight-factor pulmonary embolism rule-out criteria (Kline 2004). PERC-negative only when all eight hold: age <50, pulse <100, SaO2 >94%, and no unilateral leg swelling, hemoptysis, recent trauma or surgery, prior PE or DVT, or hormone use. Caller must already have low pretest probability as in the paper. Not a diagnosis, not a D-dimer protocol, and not altitude-adjusted PERC.
The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
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/perc",
"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/perc",
"tags": [
"perc",
"pe",
"vte",
"rule-out",
"calculator"
],
"mimeType": "application/json",
"description": "Eight-factor pulmonary embolism rule-out criteria (Kline 2004). PERC-negative only when all eight hold: age <50, pulse <100, SaO2 >94%, and no unilateral leg swelling, hemoptysis, recent trauma or surgery, prior PE or DVT, or hormone use. Caller must already have low pretest probability as in the paper. Not a diagnosis, not a D-dimer protocol, and not altitude-adjusted PERC.",
"serviceName": "magent"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"age": 40,
"prior_vte": false,
"hemoptysis": false,
"estrogen_use": false,
"spo2_percent": 98,
"heart_rate_bpm": 80,
"unilateral_leg_swelling": false,
"recent_surgery_or_trauma": false
}
},
"output": {
"type": "json",
"example": {
"formula": "perc",
"citation": {
"id": "kline-2004",
"doi": "10.1111/j.1538-7836.2004.00790.x",
"title": "Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism",
"source": "J Thromb Haemost. 2004;2(8):1247-1255",
"authors": "Kline JA, Mitchell AM, Kabrhel C, Richman PB, Courtney DM"
},
"criteria": [
{
"met": true,
"value": 40,
"factor": "age_lt_50"
},
{
"met": true,
"value": 80,
"factor": "pulse_lt_100"
},
{
"met": true,
"value": 98,
"factor": "sao2_gt_94"
},
{
"met": true,
"factor": "no_unilateral_leg_swelling"
},
{
"met": true,
"factor": "no_hemoptysis"
},
{
"met": true,
"factor": "no_recent_surgery_or_trauma"
},
{
"met": true,
"factor": "no_prior_vte"
},
{
"met": true,
"factor": "no_estrogen_use"
}
],
"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.",
"perc_negative": true,
"formula_expression": "PERC-negative iff age < 50 and pulse < 100 bpm and SaO2 > 94% and no unilateral leg swelling and no hemoptysis and no recent trauma or surgery and no prior PE or DVT and no hormone use"
}
},
"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",
"heart_rate_bpm",
"spo2_percent",
"unilateral_leg_swelling",
"hemoptysis",
"recent_surgery_or_trauma",
"prior_vte",
"estrogen_use"
],
"properties": {
"age": {
"type": "integer",
"description": "Age in years (18-120). Criterion met when age < 50; 50 does not meet."
},
"prior_vte": {
"type": "boolean",
"description": "Prior PE or DVT. true or false as assigned by the caller. Criterion met when false."
},
"hemoptysis": {
"type": "boolean",
"description": "Hemoptysis. true or false as assigned by the caller. Criterion met when false."
},
"estrogen_use": {
"type": "boolean",
"description": "Hormone or exogenous estrogen use. true or false as assigned by the caller. Criterion met when false."
},
"spo2_percent": {
"type": "number",
"description": "Oxygen saturation percent (50-100). Criterion met when SaO2 > 94; 94 does not meet."
},
"heart_rate_bpm": {
"type": "integer",
"description": "Pulse in beats per minute (integer 30-220). Criterion met when pulse < 100; 100 does not meet."
},
"unilateral_leg_swelling": {
"type": "boolean",
"description": "Unilateral leg swelling. true or false as assigned by the caller. Criterion met when false."
},
"recent_surgery_or_trauma": {
"type": "boolean",
"description": "Recent trauma or surgery. true or false as assigned by the caller. Criterion met when false."
}
}
}
},
"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.
Pay 0.005 USDC on Base to 0x836B…19Ee2. The signed payment is good for 10 minutes.
- Paid to
- 0x836B…19Ee2
- 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/perc",
"assetTransferMethod": "eip3009"
},
"payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
"amount": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 600
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {
"items": [
{
"age": 40,
"prior_vte": false,
"hemoptysis": false,
"estrogen_use": false,
"spo2_percent": 98,
"heart_rate_bpm": 80,
"unilateral_leg_swelling": false,
"recent_surgery_or_trauma": false
},
{
"age": 40,
"prior_vte": false,
"hemoptysis": false,
"estrogen_use": false,
"spo2_percent": 98,
"heart_rate_bpm": 80,
"unilateral_leg_swelling": false,
"recent_surgery_or_trauma": false
}
]
},
"type": "http",
"method": "POST"
},
"output": {
"type": "json",
"example": {
"path": "/api/calc/perc",
"count": 2,
"items": [
{
"formula": "perc",
"citation": {
"id": "kline-2004",
"doi": "10.1111/j.1538-7836.2004.00790.x",
"title": "Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism",
"source": "J Thromb Haemost. 2004;2(8):1247-1255",
"authors": "Kline JA, Mitchell AM, Kabrhel C, Richman PB, Courtney DM"
},
"criteria": [
{
"met": true,
"value": 40,
"factor": "age_lt_50"
},
{
"met": true,
"value": 80,
"factor": "pulse_lt_100"
},
{
"met": true,
"value": 98,
"factor": "sao2_gt_94"
},
{
"met": true,
"factor": "no_unilateral_leg_swelling"
},
{
"met": true,
"factor": "no_hemoptysis"
},
{
"met": true,
"factor": "no_recent_surgery_or_trauma"
},
{
"met": true,
"factor": "no_prior_vte"
},
{
"met": true,
"factor": "no_estrogen_use"
}
],
"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.",
"perc_negative": true,
"formula_expression": "PERC-negative iff age < 50 and pulse < 100 bpm and SaO2 > 94% and no unilateral leg swelling and no hemoptysis and no recent trauma or surgery and no prior PE or DVT and no hormone use"
},
{
"formula": "perc",
"citation": {
"id": "kline-2004",
"doi": "10.1111/j.1538-7836.2004.00790.x",
"title": "Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism",
"source": "J Thromb Haemost. 2004;2(8):1247-1255",
"authors": "Kline JA, Mitchell AM, Kabrhel C, Richman PB, Courtney DM"
},
"criteria": [
{
"met": true,
"value": 40,
"factor": "age_lt_50"
},
{
"met": true,
"value": 80,
"factor": "pulse_lt_100"
},
{
"met": true,
"value": 98,
"factor": "sao2_gt_94"
},
{
"met": true,
"factor": "no_unilateral_leg_swelling"
},
{
"met": true,
"factor": "no_hemoptysis"
},
{
"met": true,
"factor": "no_recent_surgery_or_trauma"
},
{
"met": true,
"factor": "no_prior_vte"
},
{
"met": true,
"factor": "no_estrogen_use"
}
],
"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.",
"perc_negative": true,
"formula_expression": "PERC-negative iff age < 50 and pulse < 100 bpm and SaO2 > 94% and no unilateral leg swelling and no hemoptysis and no recent trauma or surgery and no prior PE or DVT and no hormone use"
}
]
}
},
"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",
"heart_rate_bpm",
"spo2_percent",
"unilateral_leg_swelling",
"hemoptysis",
"recent_surgery_or_trauma",
"prior_vte",
"estrogen_use"
],
"properties": {
"age": {
"type": "integer",
"description": "Age in years (18-120). Criterion met when age < 50; 50 does not meet."
},
"prior_vte": {
"type": "boolean",
"description": "Prior PE or DVT. true or false as assigned by the caller. Criterion met when false."
},
"hemoptysis": {
"type": "boolean",
"description": "Hemoptysis. true or false as assigned by the caller. Criterion met when false."
},
"estrogen_use": {
"type": "boolean",
"description": "Hormone or exogenous estrogen use. true or false as assigned by the caller. Criterion met when false."
},
"spo2_percent": {
"type": "number",
"description": "Oxygen saturation percent (50-100). Criterion met when SaO2 > 94; 94 does not meet."
},
"heart_rate_bpm": {
"type": "integer",
"description": "Pulse in beats per minute (integer 30-220). Criterion met when pulse < 100; 100 does not meet."
},
"unilateral_leg_swelling": {
"type": "boolean",
"description": "Unilateral leg swelling. true or false as assigned by the caller. Criterion met when false."
},
"recent_surgery_or_trauma": {
"type": "boolean",
"description": "Recent trauma or surgery. true or false as assigned by the caller. Criterion met when false."
}
}
},
"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 13:15Z
- Last indexed by Roundhouse
- 2026-09-07 06:20Z
- Last enriched (probe, favicon, geo)
- 2026-09-24 14:45Z
- x402 version
- 2
- Max timeout
- 600s
- Liveness probe
- HTTP 402
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. 14 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide 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/perc, 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.