# HITS

HITS

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

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

## What it computes

Sum four caller-assigned Sherin 1998 HITS integers (hurt, insult, threaten, scream; each 1-5) and return the published total (4-20) and ≥10 screen.

## When to use

When an agent has already assigned Sherin 1998 1-5 integers for hurt, insult, threaten, and scream and needs the published total and ≥10 screen, not a diagnosis of intimate partner violence and not a patient interview.

## When not to use

- Not a medical device and not a diagnosis of intimate partner violence.
- magent does not interview the patient.
- hurt, insult, threaten, and scream are caller-assigned integers 1-5 (never=1 to frequently=5). magent does not interpret the items.
- This is Sherin 1998 HITS only (screen-positive at score ≥10). magent does not apply later variants or other IPV instruments.

## Formula

```
HITS = hurt + insult + threaten + scream; each caller-assigned 1-5 (never=1 to frequently=5); max 20; screen-positive at ≥10
```

## Citation

[HITS: a short domestic violence screening tool for use in a family practice setting](https://pubmed.ncbi.nlm.nih.gov/9669164)
Sherin KM, Sinacore JM, Li XQ, Zitter RE, Shakil A
Fam Med. 1998;30(7):508-512
DOI: none

## Worked example

### All items never (1)

Given: `hurt=1, insult=1, scream=1, threaten=1`

1. hurt 1 + insult 1 + threaten 1 + scream 1
2. Score = 4 (max 20); screen_positive false (threshold is ≥10)


### Score 10

Given: `hurt=4, insult=2, scream=2, threaten=2`

1. Score = 10
2. screen_positive true


## Also searched as

- HITS
- Hurt Insult Threaten Scream
- Sherin HITS
- domestic violence screening
- HITS score
- intimate partner violence screen
- family practice HITS
- Sherin 1998 HITS

## Parameters

- `hurt` (integer, required): Caller-assigned Sherin 1998 HITS Hurt item (integer 1-5; never=1 to frequently=5): how often the partner physically hurt the patient. magent does not interview the patient.
- `insult` (integer, required): Caller-assigned Sherin 1998 HITS Insult item (integer 1-5; never=1 to frequently=5): how often the partner insulted or talked down to the patient. magent does not interview the patient.
- `threaten` (integer, required): Caller-assigned Sherin 1998 HITS Threaten item (integer 1-5; never=1 to frequently=5): how often the partner threatened the patient with harm. magent does not interview the patient.
- `scream` (integer, required): Caller-assigned Sherin 1998 HITS Scream item (integer 1-5; never=1 to frequently=5): how often the partner screamed or cursed at the patient. magent does not interview 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/hits`
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": [
    {
      "hurt": "1",
      "insult": "1",
      "scream": "1",
      "threaten": "1"
    },
    {
      "hurt": "1",
      "insult": "1",
      "scream": "1",
      "threaten": "1"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/hits",
  "items": [
    {
      "components": [
        {
          "value": 1,
          "factor": "hurt",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "insult",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "threaten",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "scream",
          "points": 1,
          "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": "Sherin KM, Sinacore JM, Li XQ, Zitter RE, Shakil A",
        "id": "sherin-1998",
        "pmid": "9669164",
        "source": "Fam Med. 1998;30(7):508-512",
        "title": "HITS: a short domestic violence screening tool for use in a family practice setting"
      },
      "formula": "hits",
      "formula_expression": "HITS = hurt + insult + threaten + scream; each caller-assigned 1-5 (never=1 to frequently=5); max 20; screen-positive at ≥10",
      "max_score": 20,
      "score": 4,
      "screen_positive": false
    },
    {
      "components": [
        {
          "value": 1,
          "factor": "hurt",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "insult",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "threaten",
          "points": 1,
          "present": true
        },
        {
          "value": 1,
          "factor": "scream",
          "points": 1,
          "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": "Sherin KM, Sinacore JM, Li XQ, Zitter RE, Shakil A",
        "id": "sherin-1998",
        "pmid": "9669164",
        "source": "Fam Med. 1998;30(7):508-512",
        "title": "HITS: a short domestic violence screening tool for use in a family practice setting"
      },
      "formula": "hits",
      "formula_expression": "HITS = hurt + insult + threaten + scream; each caller-assigned 1-5 (never=1 to frequently=5); max 20; screen-positive at ≥10",
      "max_score": 20,
      "score": 4,
      "screen_positive": false
    }
  ]
}
```

## Response fields

- `formula` (string): hits
- `formula_expression` (string): Exact expression used
- `score` (integer): HITS points 4-20
- `max_score` (integer): 20
- `screen_positive` (boolean): true iff score ≥ 10 (Sherin 1998). Not a diagnosis of intimate partner violence.
- `components` (array): Per-item caller-assigned points
- `citation` (object): Sherin Fam Med 1998 citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "value": 1,
      "factor": "hurt",
      "points": 1,
      "present": true
    },
    {
      "value": 1,
      "factor": "insult",
      "points": 1,
      "present": true
    },
    {
      "value": 1,
      "factor": "threaten",
      "points": 1,
      "present": true
    },
    {
      "value": 1,
      "factor": "scream",
      "points": 1,
      "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": "Sherin KM, Sinacore JM, Li XQ, Zitter RE, Shakil A",
    "id": "sherin-1998",
    "pmid": "9669164",
    "source": "Fam Med. 1998;30(7):508-512",
    "title": "HITS: a short domestic violence screening tool for use in a family practice setting"
  },
  "formula": "hits",
  "formula_expression": "HITS = hurt + insult + threaten + scream; each caller-assigned 1-5 (never=1 to frequently=5); max 20; screen-positive at ≥10",
  "max_score": 20,
  "score": 4,
  "screen_positive": false
}
```

## Errors

- HTTP 400 `invalid_hits`: hurt, insult, threaten, and scream must each be an integer from 1 to 5 (Sherin 1998 never=1 to frequently=5). 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

- [PHQ-9](https://magentlab.com/docs/phq-9) — Sum nine caller-assigned Kroenke 2001 PHQ-9 integers (0-3) and return the published total (max 27), severity cutpoints, and ≥10 screen.
- [GAD-7](https://magentlab.com/docs/gad-7) — Sum seven caller-assigned Spitzer 2006 GAD-7 integers (0-3) and return the published 0-21 total, 5/10/15 severity cuts, and ≥10 case-finding flag.
- [CAGE](https://magentlab.com/docs/cage) — Sum the four Ewing 1984 CAGE items and return whether two or more answers are affirmative.

## 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.
