# MGFA Clinical Classification (Jaretzki 2000) MGFA Status: LIVE Price: $0.005 USDC `GET /api/calc/mgfa` HTML: https://magentlab.com/docs/mgfa Markdown: https://magentlab.com/docs/mgfa.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Echo the caller-assigned Jaretzki 2000 Table 1 MGFA Clinical Classification class (I, IIa, IIb, IIIa, IIIb, IVa, IVb, or V) with the published class description. Class V is intubation except routine postoperative management. A feeding tube without intubation is class IVb. ## When to use When an agent already has a Jaretzki 2000 Table 1 MGFA class as assigned by the caller and needs the published description. magent does not examine the patient, assign class from findings, map to QMG or MG-ADL, or use Osserman. ## When not to use - Not a medical device. magent does not examine the patient. - The caller assigns MGFA class I, IIa, IIb, IIIa, IIIb, IVa, IVb, or V. magent does not grade strength, inspect the eyes, or decide intubation or a feeding tube. - Jaretzki 2000 Table 1 MGFA Clinical Classification only. This is not an outcome measure; the Task Force states the classification should not be used to measure outcome (QMG is separate). - Not QMG. Not MG-ADL. Not Osserman. Not a treatment, intubation, or feeding-tube order. ## Formula ``` mgfa_class in {I, IIa, IIb, IIIa, IIIb, IVa, IVb, V} as assigned by the caller (Jaretzki 2000 Table 1 MGFA Clinical Classification). Not QMG. Not MG-ADL. Not Osserman. Not an outcome measure. ``` ## Citation [Myasthenia gravis: recommendations for clinical research standards. Task Force of the Medical Scientific Advisory Board of the Myasthenia Gravis Foundation of America](https://doi.org/10.1016/s0003-4975(00)01595-2) Jaretzki A 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS, Sanders DB Ann Thorac Surg. 2000;70(1):327-334 DOI: [10.1016/s0003-4975(00)01595-2](https://doi.org/10.1016/s0003-4975(00)01595-2) ## Worked example ### Class I ocular only Given: `mgfa_class=I` 1. mgfa_class I as assigned by the caller 2. ocular muscle weakness only; all other muscle strength is normal 3. intubation_class is false ### Class IVb feeding tube without intubation Given: `mgfa_class=IVb` 1. mgfa_class IVb as assigned by the caller 2. severe oropharyngeal/respiratory predominance; feeding tube without intubation is IVb 3. intubation_class is false ### Class V intubation Given: `mgfa_class=V` 1. mgfa_class V as assigned by the caller 2. defined by intubation with or without mechanical ventilation, except routine postoperative management 3. intubation_class is true ## Also searched as - MGFA class - MGFA Clinical Classification - Jaretzki 2000 - myasthenia gravis class - MGFA I IIa IIb - MGFA class V intubation - MGFA IVb feeding tube - Myasthenia Gravis Foundation of America class - MGFA Task Force classification ## Parameters - `mgfa_class` (string, required): Jaretzki 2000 Table 1 MGFA Clinical Classification as assigned by the caller: I, IIa, IIb, IIIa, IIIb, IVa, IVb, or V (case-sensitive; reject i, 1, II, IIA). Class I ocular only; II mild, III moderate, IV severe generalized with a = limb/axial and b = oropharyngeal/respiratory; IVb includes feeding tube without intubation; V is intubation except routine postoperative management. magent does not examine the patient. ## Bulk (POST) POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement. Method: `POST /api/calc/mgfa` Max items: 25 Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic) Status: PREVIEW - 1 to 25 items. Each item uses the same keys as the GET query parameters. - POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows. - The first invalid item fails the whole request (index in the 400 JSON). You are not charged. - HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row. - Catalog misses (empty matches, found=false) stay paid 200s inside that slot. - x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items. Example request: ```json { "items": [ { "mgfa_class": "I" }, { "mgfa_class": "I" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/mgfa Example 200: ```json { "count": 2, "path": "/api/calc/mgfa", "items": [ { "description": "Any ocular muscle weakness. May have weakness of eye closure. All other muscle strength is normal.", "components": [ { "factor": "class_I", "met": true }, { "factor": "class_IIa", "met": false }, { "factor": "class_IIb", "met": false }, { "factor": "class_IIIa", "met": false }, { "factor": "class_IIIb", "met": false }, { "factor": "class_IVa", "met": false }, { "factor": "class_IVb", "met": false }, { "factor": "class_V", "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.", "citation": { "authors": "Jaretzki A 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS, Sanders DB", "doi": "10.1016/s0003-4975(00)01595-2", "id": "jaretzki-2000", "pmid": "10921745", "source": "Ann Thorac Surg. 2000;70(1):327-334", "title": "Myasthenia gravis: recommendations for clinical research standards. Task Force of the Medical Scientific Advisory Board of the Myasthenia Gravis Foundation of America" }, "formula": "mgfa", "formula_expression": "mgfa_class in {I, IIa, IIb, IIIa, IIIb, IVa, IVb, V} as assigned by the caller (Jaretzki 2000 Table 1 MGFA Clinical Classification). Not QMG. Not MG-ADL. Not Osserman. Not an outcome measure.", "intubation_class": false, "mgfa_class": "I" }, { "description": "Any ocular muscle weakness. May have weakness of eye closure. All other muscle strength is normal.", "components": [ { "factor": "class_I", "met": true }, { "factor": "class_IIa", "met": false }, { "factor": "class_IIb", "met": false }, { "factor": "class_IIIa", "met": false }, { "factor": "class_IIIb", "met": false }, { "factor": "class_IVa", "met": false }, { "factor": "class_IVb", "met": false }, { "factor": "class_V", "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.", "citation": { "authors": "Jaretzki A 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS, Sanders DB", "doi": "10.1016/s0003-4975(00)01595-2", "id": "jaretzki-2000", "pmid": "10921745", "source": "Ann Thorac Surg. 2000;70(1):327-334", "title": "Myasthenia gravis: recommendations for clinical research standards. Task Force of the Medical Scientific Advisory Board of the Myasthenia Gravis Foundation of America" }, "formula": "mgfa", "formula_expression": "mgfa_class in {I, IIa, IIb, IIIa, IIIb, IVa, IVb, V} as assigned by the caller (Jaretzki 2000 Table 1 MGFA Clinical Classification). Not QMG. Not MG-ADL. Not Osserman. Not an outcome measure.", "intubation_class": false, "mgfa_class": "I" } ] } ``` ## Response fields - `formula` (string): mgfa - `formula_expression` (string): Published Jaretzki 2000 Table 1 class rule - `mgfa_class` (string): Caller-assigned class I, IIa, IIb, IIIa, IIIb, IVa, IVb, or V - `description` (string): Jaretzki 2000 Table 1 wording for that class - `intubation_class` (boolean): true iff mgfa_class is V - `components` (array): Per-class Tree rows class_I, class_IIa, class_IIb, class_IIIa, class_IIIb, class_IVa, class_IVb, class_V with factor and met; exactly one is met - `citation` (object): Jaretzki 2000 Ann Thorac Surg citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "description": "Any ocular muscle weakness. May have weakness of eye closure. All other muscle strength is normal.", "components": [ { "factor": "class_I", "met": true }, { "factor": "class_IIa", "met": false }, { "factor": "class_IIb", "met": false }, { "factor": "class_IIIa", "met": false }, { "factor": "class_IIIb", "met": false }, { "factor": "class_IVa", "met": false }, { "factor": "class_IVb", "met": false }, { "factor": "class_V", "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.", "citation": { "authors": "Jaretzki A 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS, Sanders DB", "doi": "10.1016/s0003-4975(00)01595-2", "id": "jaretzki-2000", "pmid": "10921745", "source": "Ann Thorac Surg. 2000;70(1):327-334", "title": "Myasthenia gravis: recommendations for clinical research standards. Task Force of the Medical Scientific Advisory Board of the Myasthenia Gravis Foundation of America" }, "formula": "mgfa", "formula_expression": "mgfa_class in {I, IIa, IIb, IIIa, IIIb, IVa, IVb, V} as assigned by the caller (Jaretzki 2000 Table 1 MGFA Clinical Classification). Not QMG. Not MG-ADL. Not Osserman. Not an outcome measure.", "intubation_class": false, "mgfa_class": "I" } ``` ## Errors - HTTP 400 `invalid_mgfa`: mgfa_class must be I, IIa, IIb, IIIa, IIIb, IVa, IVb, or V (Jaretzki 2000 MGFA Clinical Classification). Returned before settlement; you are not charged. - HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged. - HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged. - HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged. Shared HTTP 402 and 503: https://magentlab.com/docs/payments ## Related tools - [MG-ADL](https://magentlab.com/docs/mg-adl) — Sum eight caller-assigned Wolfe 1999 MG-ADL items (each integer 0-3) and return the published 0-24 total. Does not map to QMG or assign MGFA class. ## Payment Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. - GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall). - HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote. - Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering. - Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional. - Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402. - offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront. - offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization. - not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search. Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers). Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments Stdio MCP (one process per host): https://magentlab.com/docs/mcp ## Guarantees - HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON. - exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE. - HTTP 402 is unpaid only. Do not sign a second authorization because of a 503. - Execution is timeout-bounded and concurrency-capped. - Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.