# FLACC (Merkel) FLACC Status: LIVE Price: $0.005 USDC `GET /api/calc/flacc` HTML: https://magentlab.com/docs/flacc Markdown: https://magentlab.com/docs/flacc.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum five caller-assigned Merkel 1997 FLACC integers (0-2) and return the published total (max 10). ## When to use When an agent has already assigned Merkel 1997 0-2 integers for face, legs, activity, cry, and consolability and needs the published total, not a pain diagnosis, analgesic order, or later intensity cutoff. ## When not to use - Not a medical device and not a pain diagnosis or analgesic order. - Each of the five items is a caller-assigned integer 0, 1, or 2 from Merkel 1997. magent does not observe the child. - Merkel 1997 described postoperative pain scoring in children 2 months to 7 years. magent does not take an age parameter and does not restrict the caller. - Total is 0-10. magent does not add mild, moderate, or severe intensity cutoffs that are not in Merkel 1997. - Not PAINAD. ## Formula ``` FLACC = face + legs + activity + cry + consolability; each caller-assigned 0-2; max 10 ``` ## Citation [The FLACC: a behavioral scale for scoring postoperative pain in young children](https://pubmed.ncbi.nlm.nih.gov/9220806) Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S Pediatr Nurs. 1997;23(3):293-297 DOI: none ## Worked example ### All items 0 Given: `activity=0, consolability=0, cry=0, face=0, legs=0` 1. face 0 + legs 0 + activity 0 + cry 0 + consolability 0 2. Score = 0 (max 10) ### All items 2 Given: `activity=2, consolability=2, cry=2, face=2, legs=2` 1. face 2 + legs 2 + activity 2 + cry 2 + consolability 2 2. Score = 10 (max 10) ## Also searched as - FLACC - Face Legs Activity Cry Consolability - Merkel FLACC - FLACC scale - postoperative pain young children - Merkel 1997 FLACC - behavioral pain children ## Parameters - `face` (integer, required): Caller-assigned Merkel 1997 FLACC face (integer 0-2): 0 no particular expression or smile; 1 occasional grimace/frown, withdrawn or disinterested; 2 frequent/constant quivering chin, clenched jaw. magent does not observe the child. - `legs` (integer, required): Caller-assigned Merkel 1997 FLACC legs (integer 0-2): 0 normal position or relaxed; 1 uneasy, restless, tense; 2 kicking or legs drawn up. magent does not observe the child. - `activity` (integer, required): Caller-assigned Merkel 1997 FLACC activity (integer 0-2): 0 lying quietly, normal position, moves easily; 1 squirming, shifting back and forth, tense; 2 arched, rigid or jerking. magent does not observe the child. - `cry` (integer, required): Caller-assigned Merkel 1997 FLACC cry (integer 0-2): 0 no cry (awake or asleep); 1 moans or whimpers, occasional complaint; 2 crying steadily, screams or sobs, frequent complaints. magent does not observe the child. - `consolability` (integer, required): Caller-assigned Merkel 1997 FLACC consolability (integer 0-2): 0 content and relaxed; 1 reassured by occasional touching, hugging or being talked to, distractible; 2 difficult to console or comfort. magent does not observe the child. ## 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/flacc` 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": [ { "activity": "0", "consolability": "0", "cry": "0", "face": "0", "legs": "0" }, { "activity": "0", "consolability": "0", "cry": "0", "face": "0", "legs": "0" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/flacc Example 200: ```json { "count": 2, "path": "/api/calc/flacc", "items": [ { "components": [ { "value": 0, "factor": "face", "points": 0, "present": true }, { "value": 0, "factor": "legs", "points": 0, "present": true }, { "value": 0, "factor": "activity", "points": 0, "present": true }, { "value": 0, "factor": "cry", "points": 0, "present": true }, { "value": 0, "factor": "consolability", "points": 0, "present": true } ], "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": "Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S", "id": "merkel-1997", "pmid": "9220806", "source": "Pediatr Nurs. 1997;23(3):293-297", "title": "The FLACC: a behavioral scale for scoring postoperative pain in young children" }, "formula": "flacc", "formula_expression": "FLACC = face + legs + activity + cry + consolability; each caller-assigned 0-2; max 10", "max_score": 10, "score": 0, "activity": 0, "consolability": 0, "cry": 0, "face": 0, "legs": 0 }, { "components": [ { "value": 0, "factor": "face", "points": 0, "present": true }, { "value": 0, "factor": "legs", "points": 0, "present": true }, { "value": 0, "factor": "activity", "points": 0, "present": true }, { "value": 0, "factor": "cry", "points": 0, "present": true }, { "value": 0, "factor": "consolability", "points": 0, "present": true } ], "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": "Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S", "id": "merkel-1997", "pmid": "9220806", "source": "Pediatr Nurs. 1997;23(3):293-297", "title": "The FLACC: a behavioral scale for scoring postoperative pain in young children" }, "formula": "flacc", "formula_expression": "FLACC = face + legs + activity + cry + consolability; each caller-assigned 0-2; max 10", "max_score": 10, "score": 0, "activity": 0, "consolability": 0, "cry": 0, "face": 0, "legs": 0 } ] } ``` ## Response fields - `formula` (string): flacc - `formula_expression` (string): Exact expression used - `score` (integer): FLACC points 0-10 - `max_score` (integer): Always 10 - `face` (integer): Caller-assigned face points 0-2 - `legs` (integer): Caller-assigned legs points 0-2 - `activity` (integer): Caller-assigned activity points 0-2 - `cry` (integer): Caller-assigned cry points 0-2 - `consolability` (integer): Caller-assigned consolability points 0-2 - `components` (array): Per-item caller-assigned points - `citation` (object): Merkel et al. Pediatr Nurs 1997 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "value": 0, "factor": "face", "points": 0, "present": true }, { "value": 0, "factor": "legs", "points": 0, "present": true }, { "value": 0, "factor": "activity", "points": 0, "present": true }, { "value": 0, "factor": "cry", "points": 0, "present": true }, { "value": 0, "factor": "consolability", "points": 0, "present": true } ], "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": "Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S", "id": "merkel-1997", "pmid": "9220806", "source": "Pediatr Nurs. 1997;23(3):293-297", "title": "The FLACC: a behavioral scale for scoring postoperative pain in young children" }, "formula": "flacc", "formula_expression": "FLACC = face + legs + activity + cry + consolability; each caller-assigned 0-2; max 10", "max_score": 10, "score": 0, "activity": 0, "consolability": 0, "cry": 0, "face": 0, "legs": 0 } ``` ## Errors - HTTP 400 `invalid_flacc`: face, legs, activity, cry, and consolability must each be an integer 0, 1, or 2 (Merkel 1997). 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 - [PAINAD](https://magentlab.com/docs/painad) — Sum five caller-assigned Warden 2003 PAINAD integers (0-2) and return the published total (max 10). ## 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.