magent
Deterministic published-formula arithmetic plus ICD-10-CM, RxNorm, and LOINC. Pay in USDC on Base via x402.
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.
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"resourceUrl": "https://api.magentlab.com/api/calc/leiden_arthritis",
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"description": "van der Helm-van Mil 2007 Leiden prediction rule for recent-onset undifferentiated arthritis (Figure 1 / Table 2). Age × 0.02, female 1, small joints 0.5, symmetric 0.5, upper 1 or upper-and-lower 1.5, 100-mm morning-stiffness VAS 0/1/2, tender and swollen counts 0/0.5/1, CRP mg/L 0/0.5/1.5, RF 1, anti-CCP 2. Round to nearest 0.0 or 0.5. Bands ≤6 low, >6 and <8 indeterminate, ≥8 high. Not a diagnosis of RA. magent does not examine joints or assay serologies.",
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"extensions": {
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"sex": "female",
"crp_mg_l": 60,
"symmetric": true,
"anti_ccp_positive": false,
"upper_extremities": true,
"tender_joint_count": 8,
"swollen_joint_count": 8,
"small_joints_hands_feet": true,
"morning_stiffness_vas_mm": 50,
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"formula": "leiden_arthritis",
"citation": {
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"doi": "10.1002/art.22380",
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"title": "A prediction rule for disease outcome in patients with recent-onset undifferentiated arthritis: how to guide individual treatment decisions",
"source": "Arthritis Rheum. 2007;56(2):433-440",
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"present": true
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{
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"factor": "swollen_joint_count",
"points": 0.5,
"present": true
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{
"value": 60,
"factor": "crp_mg_l",
"points": 1.5,
"present": true
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{
"factor": "rheumatoid_factor_positive",
"points": 0,
"present": false
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{
"factor": "anti_ccp_positive",
"points": 0,
"present": 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.",
"leiden_band": "indeterminate",
"formula_expression": "Leiden UA score (van der Helm-van Mil 2007 Figure 1 / Table 2) = age_years*0.02 + female 1 + small_joints_hands_feet 0.5 + symmetric 0.5 + (upper_and_lower_extremities 1.5 else upper_extremities 1) + morning_stiffness_vas_mm (0–25 → 0; 26–90 → 1; >90 → 2) + tender_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + swollen_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + crp_mg_l (0–4 → 0; 5–50 → 0.5; ≥51 → 1.5) + rheumatoid_factor_positive 1 + anti_ccp_positive 2; round to nearest 0.0 or 0.5; ≤6 low, >6 and <8 indeterminate, ≥8 high; max 14; not a diagnosis of RA"
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},
"iconUrl": "https://api.magentlab.com/favicon.ico"
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"schema": {
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"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
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"properties": {
"input": {
"type": "object",
"required": [
"type",
"method"
],
"properties": {
"type": {
"type": "string",
"const": "http"
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"method": {
"enum": [
"GET",
"HEAD",
"DELETE"
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"type": "string"
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"headers": {
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"queryParams": {
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"required": [
"age",
"sex",
"small_joints_hands_feet",
"symmetric",
"upper_extremities",
"upper_and_lower_extremities",
"morning_stiffness_vas_mm",
"tender_joint_count",
"swollen_joint_count",
"crp_mg_l",
"rheumatoid_factor_positive",
"anti_ccp_positive"
],
"properties": {
"age": {
"type": "integer",
"description": "Age in years as an integer from 18 to 120 (van der Helm-van Mil 2007). Scores age_years × 0.02. magent does not assign age."
},
"sex": {
"enum": [
"female",
"male"
],
"type": "string",
"description": "Caller-assigned sex (van der Helm-van Mil 2007). female scores 1; male scores 0. magent does not assign sex."
},
"crp_mg_l": {
"type": "number",
"description": "Caller-assigned C-reactive protein in mg/L (van der Helm-van Mil 2007). Number 0–500. 0–4 scores 0; 5–50 scores 0.5; ≥51 scores 1.5. magent does not assay CRP."
},
"symmetric": {
"type": "boolean",
"description": "Symmetric joint involvement (van der Helm-van Mil 2007). true scores 0.5 and may stack with small-joint and extremity rows. magent does not examine joints."
},
"anti_ccp_positive": {
"type": "boolean",
"description": "Caller-assigned anti-CCP (ACPA) positivity (van der Helm-van Mil 2007). true scores 2. magent does not assay serologies."
},
"upper_extremities": {
"type": "boolean",
"description": "Involvement of upper extremities only (van der Helm-van Mil 2007). true scores 1 unless upper_and_lower_extremities is true, in which case this row is ignored. Mutually exclusive with the 1.5 upper-and-lower row. magent does not examine joints."
},
"tender_joint_count": {
"type": "integer",
"description": "Caller-assigned tender joint count (van der Helm-van Mil 2007). Integer 0–68. <4 scores 0; 4–10 scores 0.5; ≥11 scores 1. magent does not examine joints."
},
"swollen_joint_count": {
"type": "integer",
"description": "Caller-assigned swollen joint count (van der Helm-van Mil 2007). Integer 0–66. <4 scores 0; 4–10 scores 0.5; ≥11 scores 1. magent does not examine joints."
},
"small_joints_hands_feet": {
"type": "boolean",
"description": "Involvement of small joints of the hands or feet (van der Helm-van Mil 2007). true scores 0.5 and may stack with symmetric and the extremity row. magent does not examine joints."
},
"morning_stiffness_vas_mm": {
"type": "number",
"description": "Morning-stiffness severity on a 100-mm VAS (van der Helm-van Mil 2007), not duration in minutes. Number 0–100. 0–25 scores 0; 26–90 scores 1; >90 scores 2. magent does not take a history."
},
"rheumatoid_factor_positive": {
"type": "boolean",
"description": "Caller-assigned rheumatoid factor positivity (van der Helm-van Mil 2007). true scores 1. magent does not assay serologies."
},
"upper_and_lower_extremities": {
"type": "boolean",
"description": "Involvement of upper and lower extremities (van der Helm-van Mil 2007). true scores 1.5 and ignores upper_extremities. magent does not examine joints."
}
}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
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"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
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"name": "USD Coin",
"version": "2",
"paymentFlow": "upfront",
"resourceUrl": "https://api.magentlab.com/api/calc/leiden_arthritis",
"assetTransferMethod": "eip3009"
},
"payTo": "0x836Be278f1739fB4308091cD1852F7971Bc19Ee2",
"amount": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 600
}
]Extensions
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"morning_stiffness_vas_mm": 50,
"rheumatoid_factor_positive": false,
"upper_and_lower_extremities": false
}
]
},
"type": "http",
"method": "POST"
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"output": {
"type": "json",
"example": {
"path": "/api/calc/leiden_arthritis",
"count": 2,
"items": [
{
"score": 7.5,
"formula": "leiden_arthritis",
"citation": {
"id": "van-der-helm-van-mil-2007",
"doi": "10.1002/art.22380",
"pmid": "17265478",
"title": "A prediction rule for disease outcome in patients with recent-onset undifferentiated arthritis: how to guide individual treatment decisions",
"source": "Arthritis Rheum. 2007;56(2):433-440",
"authors": "van der Helm-van Mil AH, le Cessie S, van Dongen H, Breedveld FC, Toes RE, Huizinga TW"
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{
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"present": false
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"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.",
"leiden_band": "indeterminate",
"formula_expression": "Leiden UA score (van der Helm-van Mil 2007 Figure 1 / Table 2) = age_years*0.02 + female 1 + small_joints_hands_feet 0.5 + symmetric 0.5 + (upper_and_lower_extremities 1.5 else upper_extremities 1) + morning_stiffness_vas_mm (0–25 → 0; 26–90 → 1; >90 → 2) + tender_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + swollen_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + crp_mg_l (0–4 → 0; 5–50 → 0.5; ≥51 → 1.5) + rheumatoid_factor_positive 1 + anti_ccp_positive 2; round to nearest 0.0 or 0.5; ≤6 low, >6 and <8 indeterminate, ≥8 high; max 14; not a diagnosis of RA"
},
{
"score": 7.5,
"formula": "leiden_arthritis",
"citation": {
"id": "van-der-helm-van-mil-2007",
"doi": "10.1002/art.22380",
"pmid": "17265478",
"title": "A prediction rule for disease outcome in patients with recent-onset undifferentiated arthritis: how to guide individual treatment decisions",
"source": "Arthritis Rheum. 2007;56(2):433-440",
"authors": "van der Helm-van Mil AH, le Cessie S, van Dongen H, Breedveld FC, Toes RE, Huizinga TW"
},
"max_score": 14,
"components": [
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"factor": "age",
"points": 0.96,
"present": true
},
{
"value": "female",
"factor": "female",
"points": 1,
"present": true
},
{
"factor": "small_joints_hands_feet",
"points": 0.5,
"present": true
},
{
"factor": "symmetric",
"points": 0.5,
"present": true
},
{
"factor": "upper_and_lower_extremities",
"points": 0,
"present": false
},
{
"factor": "upper_extremities",
"points": 1,
"present": true
},
{
"value": 50,
"factor": "morning_stiffness_vas_mm",
"points": 1,
"present": true
},
{
"value": 8,
"factor": "tender_joint_count",
"points": 0.5,
"present": true
},
{
"value": 8,
"factor": "swollen_joint_count",
"points": 0.5,
"present": true
},
{
"value": 60,
"factor": "crp_mg_l",
"points": 1.5,
"present": true
},
{
"factor": "rheumatoid_factor_positive",
"points": 0,
"present": false
},
{
"factor": "anti_ccp_positive",
"points": 0,
"present": 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.",
"leiden_band": "indeterminate",
"formula_expression": "Leiden UA score (van der Helm-van Mil 2007 Figure 1 / Table 2) = age_years*0.02 + female 1 + small_joints_hands_feet 0.5 + symmetric 0.5 + (upper_and_lower_extremities 1.5 else upper_extremities 1) + morning_stiffness_vas_mm (0–25 → 0; 26–90 → 1; >90 → 2) + tender_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + swollen_joint_count (<4 → 0; 4–10 → 0.5; ≥11 → 1) + crp_mg_l (0–4 → 0; 5–50 → 0.5; ≥51 → 1.5) + rheumatoid_factor_positive 1 + anti_ccp_positive 2; round to nearest 0.0 or 0.5; ≤6 low, >6 and <8 indeterminate, ≥8 high; max 14; not a diagnosis of RA"
}
]
}
},
"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",
"sex",
"small_joints_hands_feet",
"symmetric",
"upper_extremities",
"upper_and_lower_extremities",
"morning_stiffness_vas_mm",
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"swollen_joint_count",
"crp_mg_l",
"rheumatoid_factor_positive",
"anti_ccp_positive"
],
"properties": {
"age": {
"type": "integer",
"description": "Age in years as an integer from 18 to 120 (van der Helm-van Mil 2007). Scores age_years × 0.02. magent does not assign age."
},
"sex": {
"enum": [
"female",
"male"
],
"type": "string",
"description": "Caller-assigned sex (van der Helm-van Mil 2007). female scores 1; male scores 0. magent does not assign sex."
},
"crp_mg_l": {
"type": "number",
"description": "Caller-assigned C-reactive protein in mg/L (van der Helm-van Mil 2007). Number 0–500. 0–4 scores 0; 5–50 scores 0.5; ≥51 scores 1.5. magent does not assay CRP."
},
"symmetric": {
"type": "boolean",
"description": "Symmetric joint involvement (van der Helm-van Mil 2007). true scores 0.5 and may stack with small-joint and extremity rows. magent does not examine joints."
},
"anti_ccp_positive": {
"type": "boolean",
"description": "Caller-assigned anti-CCP (ACPA) positivity (van der Helm-van Mil 2007). true scores 2. magent does not assay serologies."
},
"upper_extremities": {
"type": "boolean",
"description": "Involvement of upper extremities only (van der Helm-van Mil 2007). true scores 1 unless upper_and_lower_extremities is true, in which case this row is ignored. Mutually exclusive with the 1.5 upper-and-lower row. magent does not examine joints."
},
"tender_joint_count": {
"type": "integer",
"description": "Caller-assigned tender joint count (van der Helm-van Mil 2007). Integer 0–68. <4 scores 0; 4–10 scores 0.5; ≥11 scores 1. magent does not examine joints."
},
"swollen_joint_count": {
"type": "integer",
"description": "Caller-assigned swollen joint count (van der Helm-van Mil 2007). Integer 0–66. <4 scores 0; 4–10 scores 0.5; ≥11 scores 1. magent does not examine joints."
},
"small_joints_hands_feet": {
"type": "boolean",
"description": "Involvement of small joints of the hands or feet (van der Helm-van Mil 2007). true scores 0.5 and may stack with symmetric and the extremity row. magent does not examine joints."
},
"morning_stiffness_vas_mm": {
"type": "number",
"description": "Morning-stiffness severity on a 100-mm VAS (van der Helm-van Mil 2007), not duration in minutes. Number 0–100. 0–25 scores 0; 26–90 scores 1; >90 scores 2. magent does not take a history."
},
"rheumatoid_factor_positive": {
"type": "boolean",
"description": "Caller-assigned rheumatoid factor positivity (van der Helm-van Mil 2007). true scores 1. magent does not assay serologies."
},
"upper_and_lower_extremities": {
"type": "boolean",
"description": "Involvement of upper and lower extremities (van der Helm-van Mil 2007). true scores 1.5 and ignores upper_extremities. magent does not examine joints."
}
}
},
"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": {
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},
"example": {
"type": "object"
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}
}Provenance
- Seen in the source catalog
- 2026-08-31 13:30Z
- Last indexed by Roundhouse
- 2026-09-07 06:20Z
- Last enriched (probe, favicon, geo)
- 2026-09-22 13:15Z
- 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. 10 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/leiden_arthritis, 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.