# BARS (Behavioural Activity Rating Scale)

BARS

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

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

## What it computes

Return the Swift 2002 Behavioural Activity Rating Scale (BARS) 1-7 from a caller-assigned integer, with a stable label.

## When to use

When an agent already has a BARS integer 1, 2, 3, 4, 5, 6, or 7 as in Swift 2002 and needs the published score and label. magent does not observe the patient. Not RASS and not a diagnosis.

## When not to use

- Not a medical device. magent does not observe the patient.
- Not RASS (Sessler 2002). BARS is Swift 2002 integers 1-7 only. Stable bars_label tokens are not a published class.
- Not a diagnosis. The caller assigns bars 1-7. magent does not examine the patient or apply restraint.

## Formula

```
BARS = caller-assigned integer 1, 2, 3, 4, 5, 6, or 7 (Swift 2002); max 7
```

## Citation

[Validation of the Behavioural Activity Rating Scale (BARS): a novel measure of activity in agitated patients](https://doi.org/10.1016/s0022-3956(01)00052-8)
Swift RH, Harrigan EP, Cappelleri JC, Kramer D, Chandler LP
J Psychiatr Res. 2002;36(2):87-95
DOI: [10.1016/s0022-3956(01)00052-8](https://doi.org/10.1016/s0022-3956(01)00052-8)

## Worked example

### BARS 4 quiet and awake

Given: `bars=4`

1. bars 4 → score 4; max 7; bars 4; quiet_and_awake


### BARS 1 difficult to rouse

Given: `bars=1`

1. bars 1 → score 1; max 7; bars 1; difficult_to_rouse


## Also searched as

- BARS
- Behavioural Activity Rating Scale
- Behavioral Activity Rating Scale
- Swift BARS
- BARS score
- activity rating scale
- agitation rating scale

## Parameters

- `bars` (integer, required): Swift 2002 Behavioural Activity Rating Scale integer 1, 2, 3, 4, 5, 6, or 7 as assigned by the caller (1 difficult or unable to rouse; 2 asleep but responds normally to verbal or physical contact; 3 drowsy, appears sedated; 4 quiet and awake, normal level of activity; 5 signs of overt physical or verbal activity, calms with instructions; 6 extremely or continuously active, not requiring restraint; 7 violent, requires restraint). magent does not observe 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/bars`
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": [
    {
      "bars": "4"
    },
    {
      "bars": "4"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/bars",
  "items": [
    {
      "components": [
        {
          "factor": "bars",
          "points": 4,
          "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": "Swift RH, Harrigan EP, Cappelleri JC, Kramer D, Chandler LP",
        "doi": "10.1016/s0022-3956(01)00052-8",
        "id": "swift-2002",
        "pmid": "11777497",
        "source": "J Psychiatr Res. 2002;36(2):87-95",
        "title": "Validation of the Behavioural Activity Rating Scale (BARS): a novel measure of activity in agitated patients"
      },
      "formula": "bars",
      "formula_expression": "BARS = caller-assigned integer 1, 2, 3, 4, 5, 6, or 7 (Swift 2002); max 7",
      "max_score": 7,
      "score": 4,
      "bars": 4,
      "bars_label": "quiet_and_awake"
    },
    {
      "components": [
        {
          "factor": "bars",
          "points": 4,
          "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": "Swift RH, Harrigan EP, Cappelleri JC, Kramer D, Chandler LP",
        "doi": "10.1016/s0022-3956(01)00052-8",
        "id": "swift-2002",
        "pmid": "11777497",
        "source": "J Psychiatr Res. 2002;36(2):87-95",
        "title": "Validation of the Behavioural Activity Rating Scale (BARS): a novel measure of activity in agitated patients"
      },
      "formula": "bars",
      "formula_expression": "BARS = caller-assigned integer 1, 2, 3, 4, 5, 6, or 7 (Swift 2002); max 7",
      "max_score": 7,
      "score": 4,
      "bars": 4,
      "bars_label": "quiet_and_awake"
    }
  ]
}
```

## Response fields

- `formula` (string): bars
- `formula_expression` (string): Published BARS integer rule
- `score` (integer): Same as bars (1-7)
- `max_score` (integer): 7
- `bars` (integer): Caller-assigned Swift 2002 BARS integer 1-7
- `bars_label` (string): Stable token for that integer: difficult_to_rouse, asleep_but_responds, drowsy_appears_sedated, quiet_and_awake, signs_of_overt_activity, extremely_or_continuously_active, or violent_requires_restraint
- `components` (array): bars component
- `citation` (object): Swift 2002
- `disclaimer` (string): Not a medical device

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "factor": "bars",
      "points": 4,
      "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": "Swift RH, Harrigan EP, Cappelleri JC, Kramer D, Chandler LP",
    "doi": "10.1016/s0022-3956(01)00052-8",
    "id": "swift-2002",
    "pmid": "11777497",
    "source": "J Psychiatr Res. 2002;36(2):87-95",
    "title": "Validation of the Behavioural Activity Rating Scale (BARS): a novel measure of activity in agitated patients"
  },
  "formula": "bars",
  "formula_expression": "BARS = caller-assigned integer 1, 2, 3, 4, 5, 6, or 7 (Swift 2002); max 7",
  "max_score": 7,
  "score": 4,
  "bars": 4,
  "bars_label": "quiet_and_awake"
}
```

## Errors

- HTTP 400 `invalid_bars`: BARS needs bars as an integer from 1 to 7 (Swift 2002). 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

- [RASS](https://magentlab.com/docs/rass) — Return the Sessler 2002 Richmond Agitation-Sedation Scale term and description from a caller-assigned integer -5 to +4.

## 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.