# FLACC Pain Scale Calculator (Merkel 1997)

> FLACC Pain Scale Calculator (Merkel 1997) is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Computes the Merkel 1997 FLACC pediatric pain score (0–10) by summing five caller-assigned behavioral items: face, legs, activity, cry, and consolability.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/flacc
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/flacc-pain-scale-calculator-merkel-1997-2662229f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9CcT3VpowATGscNUTDPd6

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability flacc-pain-scale-calculator-merkel-1997-2662229f
```

Example prompt: Calculate the Merkel 1997 FLACC score for a child where face is 1 (occasional grimace), legs is 2 (kicking), activity is 1 (squirming), cry is 0 (no cry), and consolability is 1 (reassured by touch) — what's the total out of 10?

## When to prefer this

Use this endpoint when you need a fast, reproducible arithmetic FLACC sum per Merkel 1997 and already have all five behavioral item scores assigned by a clinician or observer. Prefer it over manual addition to reduce transcription errors in documentation workflows. Do not use it as a substitute for clinical observation, pain diagnosis, or analgesic decision-making; it is a calculation aid, not a clinical decision support tool. Not applicable for adult patients (use PAINAD or other adult scales) or when fewer than five FLACC items are available.

## Known failure modes

- Missing required parameter (face, legs, activity, cry, or consolability) returns a validation error
- Value outside 0–2 integer range causes a schema validation failure
- Non-integer values (e.g. floats or strings) rejected by input schema
- All zeros input returns 0 (valid, not an error — indicates minimal behavioral distress signs)

## How this service works

Merkel 1997 FLACC from five caller-assigned 0-2 items (face, legs, activity, cry, consolability) using that paper's 0/1/2 descriptors. magent sums only (max 10) and does not observe the child. No later intensity cutoffs. Not a pain diagnosis or analgesic order. Not PAINAD.

## Output

Returns the summed FLACC total score as an integer between 0 and 10, computed strictly by adding the five caller-provided item scores (face + legs + activity + cry + consolability) per the Merkel 1997 original scale. Does not include pain severity interpretation bands, treatment recommendations, or diagnostic conclusions.

## Request schema (JSON Schema)

```json
{
 "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": [
      "face",
      "legs",
      "activity",
      "cry",
      "consolability"
     ],
     "properties": {
      "cry": {
       "type": "integer",
       "description": "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."
      },
      "face": {
       "type": "integer",
       "description": "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": {
       "type": "integer",
       "description": "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": {
       "type": "integer",
       "description": "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."
      },
      "consolability": {
       "type": "integer",
       "description": "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."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/flacc-pain-scale-calculator-merkel-1997-2662229f/health.json
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