# Pediatric Crohn's Disease Activity Index (PCDAI) Calculator

> Pediatric Crohn's Disease Activity Index (PCDAI) Calculator is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Computes the Hyams 1991 PCDAI score (0–100) by summing eleven caller-assigned item points for pediatric Crohn's disease activity assessment.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/pcdai
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pediatric-crohn-s-disease-activity-index-pcdai-calculator-90ef875f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Eg42IMgbyDLle4eA25n_9

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 pediatric-crohn-s-disease-activity-index-pcdai-calculator-90ef875f
```

Example prompt: Calculate the PCDAI score for this patient: abdominal pain 5 points, stools 5 points, well-being 5 points, hematocrit 2.5 points, ESR 2.5 points, albumin 5 points, weight 5 points, height 0 points, abdomen 5 points, perirectal 0 points, extra-intestinal 0 points.

## When to prefer this

Use this endpoint when you need a fast, deterministic arithmetic computation of the Hyams 1991 PCDAI total from already-assigned item points. Prefer it over manual calculation to avoid arithmetic errors in multi-item scoring. Do not use it as a substitute for CDAI (adult Crohn's), SES-CD (endoscopic), or PUCAI (ulcerative colitis); those are separate instruments.

## Known failure modes

- Missing required query parameters returns an error
- Non-valid point values (not in the allowed set for each item) may produce unexpected sums or errors
- Score interpretation (mild/moderate/severe bands) is not provided by the endpoint
- Caller-assigned item points that do not reflect actual clinical findings produce a meaningless score

## How this service works

Hyams 1991 Pediatric Crohn's Disease Activity Index (PCDAI): eleven caller-assigned item points. hematocrit and esr are 0, 2.5, or 5; the other nine are 0, 5, or 10. magent sums only (max 100) and does not return activity bands. magent does not examine the child or assign hematocrit age/sex tables. Not a diagnosis. Not CDAI, SES-CD, or PUCAI.

## Output

Returns the total PCDAI score as a numeric sum (0–100) of the eleven caller-supplied item points. Does not return activity severity bands, diagnostic labels, or clinical interpretation. The calling system is responsible for assigning valid item point values per the Hyams 1991 criteria.

## 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": [
      "abdominal_pain",
      "stools",
      "well_being",
      "hematocrit",
      "esr",
      "albumin",
      "weight",
      "height",
      "abdomen",
      "perirectal",
      "extra_intestinal"
     ],
     "properties": {
      "esr": {
       "type": "number",
       "description": "Caller-assigned Hyams 1991 PCDAI erythrocyte sedimentation rate points (number 0, 2.5, or 5): 0 for ESR <20 mm/h; 2.5 for 20-50; 5 for >50. magent does not assay ESR. magent does not examine the child."
      },
      "height": {
       "type": "integer",
       "description": "Caller-assigned Hyams 1991 PCDAI height points (integer 0, 5, or 10): at diagnosis 0 <1 channel decrease, 5 ≥1 and <2 channel decrease, 10 ≥2 channel decrease; at follow-up 0 height velocity ≥-1 SD, 5 <-1 SD and >-2 SD, 10 ≤-2 SD. magent does not measure height. magent does not examine the child."
      },
      "stools": {
       "type": "integer",
       "description": "Caller-assigned Hyams 1991 PCDAI stools per day points (integer 0, 5, or 10): 0 for 0-1 liquid stools, no blood; 5 for up to 2 semi-formed with small blood, or 2-5 liquid; 10 for gross bleeding, or ≥6 liquid, or nocturnal diarrhea. magent does not examine the child."
      },
      "weight": {
       "type": "integer",
       "description": "Caller-assigned Hyams 1991 PCDAI weight points (integer 0, 5, or 10): 0 weight gain or voluntary stable/loss; 5 involuntary stable or weight loss 1-9%; 10 weight loss ≥10%. magent does not examine the child."
      },
      "abdomen": {
       "type": "integer",
       "description": "Caller-assigned Hyams 1991 PCDAI abdomen points (integer 0, 5, or 10): 0 no tenderness, no mass; 5 tenderness, or mass without tenderness; 10 tenderness, involuntary guarding, definite mass. magent does not examine the child."
      },
      "albumin": {
       "type": "integer",
       "description": "Caller-assigned Hyams 1991 PCDAI albumin p
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pediatric-crohn-s-disease-activity-index-pcdai-calculator-90ef875f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)