# FACE DROPS Lyme vs Bell palsy FACE DROPS Status: LIVE Price: $0.005 USDC `GET /api/calc/face_drops` HTML: https://magentlab.com/docs/face-drops Markdown: https://magentlab.com/docs/face-drops.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum the seven McEntire 2025 FACE DROPS criteria from caller-assigned flags and return whether the total favors Bell palsy (score ≤4), is indeterminate (5–6), or favors Lyme disease-associated facial palsy (score ≥7). ## When to use When an agent already has the seven McEntire 2025 FACE DROPS items assigned as present or absent and needs the published −1 to 28 total and the paper's ≤4 / 5–6 / ≥7 classification, not a Lyme test, serology order, facial examination, or stroke mimic score. ## When not to use - Not a medical device. Not a Lyme test and not a diagnosis of Bell palsy or Lyme disease-associated facial palsy. magent does not examine the face or order serology. - Each item is a caller-assigned boolean. Scores ≤4 predicted Bell palsy and scores ≥7 predicted Lyme disease-associated facial palsy in McEntire 2025; 5–6 is indeterminate. magent does not invent extra cutoffs or probabilities. - This is the McEntire 2025 seven-criterion FACE DROPS instrument only, not the 2024 abstract FACE DROP weights and not a stroke FACE-DROPS mimic score. ## Formula ``` FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025) ``` ## Citation [FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy](https://doi.org/10.1212/CPJ.0000000000200476) McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK Neurol Clin Pract. 2025;15(3):e200476 DOI: [10.1212/CPJ.0000000000200476](https://doi.org/10.1212/CPJ.0000000000200476) ## Worked example ### All seven flags false Given: `aches=false, cephalalgia=false, dermatomal_or_radicular=false, exhaustion=false, fever=false, otalgia_or_postauricular_pain=false, stiff_neck=false` 1. Fever, aches, cephalalgia, exhaustion, dermatomal or radicular pattern, otalgia or postauricular pain, and stiff neck false → 0 each 2. Score = 0 (max 28); classification favors_bell_palsy because score ≤4 ### Fever only Given: `aches=false, cephalalgia=false, dermatomal_or_radicular=false, exhaustion=false, fever=true, otalgia_or_postauricular_pain=false, stiff_neck=false` 1. Fever true → +8; remaining flags false → 0 2. Score = 8 (max 28); classification favors_ldfp because score ≥7 ### Otalgia or postauricular pain only Given: `aches=false, cephalalgia=false, dermatomal_or_radicular=false, exhaustion=false, fever=false, otalgia_or_postauricular_pain=true, stiff_neck=false` 1. Otalgia or postauricular pain true → −1; remaining flags false → 0 2. Score = −1 (max 28); classification favors_bell_palsy because score ≤4 ## Also searched as - FACE DROPS - Lyme facial palsy - Bell palsy vs Lyme - McEntire FACE DROPS - LDFP score - Lyme disease-associated facial palsy - nuchal rigidity facial palsy - acute facial palsy Lyme ## Parameters - `fever` (boolean, required): Fever (McEntire 2025, +8 if true). true or false as assigned by the caller. magent does not examine the patient or measure temperature. - `aches` (boolean, required): Arthralgia or myalgia (McEntire 2025, +6 if true). true or false as assigned by the caller. magent does not examine the patient. - `cephalalgia` (boolean, required): Headache / cephalalgia (McEntire 2025, +3 if true). true or false as assigned by the caller. magent does not examine the patient. - `exhaustion` (boolean, required): Unusual fatigue / exhaustion (McEntire 2025, +4 if true). true or false as assigned by the caller. magent does not examine the patient. - `dermatomal_or_radicular` (boolean, required): Dermatomal or radicular pattern (transverse myelitis or radiculitis) (McEntire 2025, +4 if true). true or false as assigned by the caller. magent does not examine the patient. - `otalgia_or_postauricular_pain` (boolean, required): Otalgia or postauricular pain (McEntire 2025, −1 if true). true or false as assigned by the caller. magent does not examine the patient. - `stiff_neck` (boolean, required): Stiff neck / nuchal rigidity (McEntire 2025, +3 if true). true or false as assigned by the caller. 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/face_drops` 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": [ { "aches": "false", "cephalalgia": "false", "dermatomal_or_radicular": "false", "exhaustion": "false", "fever": "false", "otalgia_or_postauricular_pain": "false", "stiff_neck": "false" }, { "aches": "false", "cephalalgia": "false", "dermatomal_or_radicular": "false", "exhaustion": "false", "fever": "false", "otalgia_or_postauricular_pain": "false", "stiff_neck": "false" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/face-drops Example 200: ```json { "count": 2, "path": "/api/calc/face_drops", "items": [ { "components": [ { "factor": "fever", "points": 0, "present": false }, { "factor": "aches", "points": 0, "present": false }, { "factor": "cephalalgia", "points": 0, "present": false }, { "factor": "exhaustion", "points": 0, "present": false }, { "factor": "dermatomal_or_radicular", "points": 0, "present": false }, { "factor": "otalgia_or_postauricular_pain", "points": 0, "present": false }, { "factor": "stiff_neck", "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.", "citation": { "authors": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK", "doi": "10.1212/CPJ.0000000000200476", "id": "mcentire-2025", "pmid": "40290705", "source": "Neurol Clin Pract. 2025;15(3):e200476", "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy" }, "formula": "face_drops", "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)", "max_score": 28, "score": 0, "classification": "favors_bell_palsy" }, { "components": [ { "factor": "fever", "points": 0, "present": false }, { "factor": "aches", "points": 0, "present": false }, { "factor": "cephalalgia", "points": 0, "present": false }, { "factor": "exhaustion", "points": 0, "present": false }, { "factor": "dermatomal_or_radicular", "points": 0, "present": false }, { "factor": "otalgia_or_postauricular_pain", "points": 0, "present": false }, { "factor": "stiff_neck", "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.", "citation": { "authors": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK", "doi": "10.1212/CPJ.0000000000200476", "id": "mcentire-2025", "pmid": "40290705", "source": "Neurol Clin Pract. 2025;15(3):e200476", "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy" }, "formula": "face_drops", "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)", "max_score": 28, "score": 0, "classification": "favors_bell_palsy" } ] } ``` ## Response fields - `formula` (string): face_drops - `formula_expression` (string): Exact expression used - `score` (integer): FACE DROPS points -1 to 28 (McEntire 2025) - `max_score` (integer): 28 - `classification` (string): favors_bell_palsy if score ≤4, indeterminate if 5–6, favors_ldfp if score ≥7 (McEntire 2025). Not a diagnosis. - `components` (array): Per-criterion points - `citation` (object): McEntire et al. Neurol Clin Pract 2025 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "factor": "fever", "points": 0, "present": false }, { "factor": "aches", "points": 0, "present": false }, { "factor": "cephalalgia", "points": 0, "present": false }, { "factor": "exhaustion", "points": 0, "present": false }, { "factor": "dermatomal_or_radicular", "points": 0, "present": false }, { "factor": "otalgia_or_postauricular_pain", "points": 0, "present": false }, { "factor": "stiff_neck", "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.", "citation": { "authors": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK", "doi": "10.1212/CPJ.0000000000200476", "id": "mcentire-2025", "pmid": "40290705", "source": "Neurol Clin Pract. 2025;15(3):e200476", "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy" }, "formula": "face_drops", "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)", "max_score": 28, "score": 0, "classification": "favors_bell_palsy" } ``` ## Errors - HTTP 400 `invalid_flag`: boolean clinical flags must be true or false 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 - [HINTS](https://magentlab.com/docs/hints) — Apply the Kattah 2009 three-step HINTS exam (Head-Impulse, Nystagmus, Test-of-Skew) from three caller-assigned flags and return whether any dangerous central sign is present. - [ROSIER](https://magentlab.com/docs/rosier) — Sum the seven Nor 2005 ROSIER items from caller-assigned flags and return whether the score is greater than 0 (stroke more likely). - [FAST-ED](https://magentlab.com/docs/fast-ed) — Sum Lima 2016 Field Assessment Stroke Triage for Emergency Destination (FAST-ED) points from caller-assigned facial palsy, arm weakness, speech, eye deviation, and neglect, and return whether the total suggests large-vessel occlusion (score ≥4) plus the published LVO-rate band. ## 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.