# Lansky Play-Performance Scale

Lansky

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/lansky`
HTML: https://magentlab.com/docs/lansky
Markdown: https://magentlab.com/docs/lansky.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Return the Lansky 1987 Play-Performance Scale 0-100 from a caller-assigned integer, with a stable label.

## When to use

When an agent already has a Lansky Play-Performance Scale 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 as in Lansky 1987 (parent-rated play-performance over the past week) and needs the published score and label. magent does not observe the child or assign performance status. Not Karnofsky. Not ECOG.

## When not to use

- Not a medical device and not a performance-status assignment. magent does not observe the child.
- Lansky 1987 Play-Performance Scale decades 0-100. Grade 0 (unresponsive) is scored. Parent-rated play-performance over the past week. Ages 1-16 in Lansky 1987; the caller assigns lps.
- Not Karnofsky and not ECOG. The caller assigns lps 0-100. magent does not examine the child.

## Formula

```
Lansky 1987 Play-Performance Scale = caller-assigned integer 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 (Lansky 1987); max 100; grade 0 (unresponsive) is scored
```

## Citation

[The measurement of performance in childhood cancer patients](https://doi.org/10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J)
Lansky SB, List MA, Lansky LL, Ritter-Sterr C, Miller DR
Cancer. 1987;60(7):1651-1656
DOI: [10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J](https://doi.org/10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J)

## Worked example

### LPS 100 fully active

Given: `lps=100`

1. lps 100 → score 100; max 100; lps 100; fully_active


### LPS 0 unresponsive

Given: `lps=0`

1. lps 0 → score 0; max 100; lps 0; unresponsive


## Also searched as

- Lansky Play-Performance Scale
- Lansky score
- LPS
- Lansky 1987
- Play-Performance Scale
- pediatric play performance
- Lansky PPS

## Parameters

- `lps` (integer, required): Lansky 1987 Play-Performance Scale 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 as assigned by the caller from parent-rated play-performance over the past week (100 fully active, normal; 90 minor restrictions in physically strenuous activity; 80 active, but tires more quickly; 70 greater restriction of play and less time spent in play; 60 up and around, but active play minimal, keeps busy with quieter activities; 50 lying around much of the day, but gets dressed, no active play, participates in all quiet play and activities; 40 mostly in bed, participates in quiet activities; 30 in bed, needs assistance even for quiet play; 20 sleeping often, play entirely limited to very passive activities; 10 does not play, does not get out of bed; 0 unresponsive). Grade 0 (unresponsive) is scored. 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/lansky`
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": [
    {
      "lps": "100"
    },
    {
      "lps": "100"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/lansky

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/lansky",
  "items": [
    {
      "components": [
        {
          "factor": "lps",
          "points": 100,
          "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": "Lansky SB, List MA, Lansky LL, Ritter-Sterr C, Miller DR",
        "doi": "10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J",
        "id": "lansky-1987",
        "pmid": "3621134",
        "source": "Cancer. 1987;60(7):1651-1656",
        "title": "The measurement of performance in childhood cancer patients"
      },
      "formula": "lansky",
      "formula_expression": "Lansky 1987 Play-Performance Scale = caller-assigned integer 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 (Lansky 1987); max 100; grade 0 (unresponsive) is scored",
      "max_score": 100,
      "score": 100,
      "lps": 100,
      "lps_label": "fully_active"
    },
    {
      "components": [
        {
          "factor": "lps",
          "points": 100,
          "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": "Lansky SB, List MA, Lansky LL, Ritter-Sterr C, Miller DR",
        "doi": "10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J",
        "id": "lansky-1987",
        "pmid": "3621134",
        "source": "Cancer. 1987;60(7):1651-1656",
        "title": "The measurement of performance in childhood cancer patients"
      },
      "formula": "lansky",
      "formula_expression": "Lansky 1987 Play-Performance Scale = caller-assigned integer 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 (Lansky 1987); max 100; grade 0 (unresponsive) is scored",
      "max_score": 100,
      "score": 100,
      "lps": 100,
      "lps_label": "fully_active"
    }
  ]
}
```

## Response fields

- `formula` (string): lansky
- `formula_expression` (string): Published Lansky decade rule
- `score` (integer): Same as lps (0-100 by tens)
- `max_score` (integer): 100
- `lps` (integer): Caller-assigned Lansky 1987 Play-Performance Scale 0-100 by tens
- `lps_label` (string): Stable token for that decade: fully_active, minor_restriction, active_tires, restricted_play, quiet_activities, lying_around, mostly_in_bed, bedbound, often_sleeping, no_play, or unresponsive
- `components` (array): lps component
- `citation` (object): Lansky 1987
- `disclaimer` (string): Not a medical device

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "factor": "lps",
      "points": 100,
      "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": "Lansky SB, List MA, Lansky LL, Ritter-Sterr C, Miller DR",
    "doi": "10.1002/1097-0142(19871001)60:7<1651::AID-CNCR2820600738>3.0.CO;2-J",
    "id": "lansky-1987",
    "pmid": "3621134",
    "source": "Cancer. 1987;60(7):1651-1656",
    "title": "The measurement of performance in childhood cancer patients"
  },
  "formula": "lansky",
  "formula_expression": "Lansky 1987 Play-Performance Scale = caller-assigned integer 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 (Lansky 1987); max 100; grade 0 (unresponsive) is scored",
  "max_score": 100,
  "score": 100,
  "lps": 100,
  "lps_label": "fully_active"
}
```

## Errors

- HTTP 400 `invalid_lansky`: lps must be 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 (Lansky 1987). Grade 0 (unresponsive) is scored. 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

- [Karnofsky](https://magentlab.com/docs/karnofsky) — Return the Karnofsky 1949 Performance Status 10-100 from a caller-assigned integer, with a stable label.

## 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.