# Rome IV centrally mediated abdominal pain syndrome

Rome IV CAPS

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/rome_iv_caps`
HTML: https://magentlab.com/docs/rome-iv-caps
Markdown: https://magentlab.com/docs/rome-iv-caps.md

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

## What it computes

Apply the Keefer 2016 Rome IV centrally mediated abdominal pain syndrome (CAPS / D1) diagnostic criteria and return whether the published CAPS box holds (rome_iv_caps).

## When to use

When an agent already has the seven caller-assigned Keefer 2016 Rome IV CAPS flags and needs whether the published CAPS box holds. magent does not examine the patient or judge feigning beyond the caller flag.

## When not to use

- Not a medical device.
- Not a diagnosis. magent does not diagnose centrally mediated abdominal pain syndrome.
- The caller assigns the seven flags. magent does not examine the patient or judge feigning beyond the caller flag.
- This tool is Keefer 2016 Rome IV CAPS (D1) only. Psychosocial comorbidity is copy-only and is not parsed. Not Rome IV IBS (Mearin 2016). Not narcotic bowel syndrome (NBS).

## Formula

```
rome_iv_caps iff continuous_or_nearly_continuous_abdominal_pain and no_or_only_occasional_relationship_with_physiological_events and pain_limits_daily_functioning and pain_not_feigned and not_explained_by_another_gi_or_medical_condition and fulfilled_last_3_months and onset_at_least_6_months (Keefer 2016 Rome IV CAPS / D1)
```

## Citation

[Centrally Mediated Disorders of Gastrointestinal Pain](https://doi.org/10.1053/j.gastro.2016.02.034)
Keefer L, Drossman DA, Guthrie E, Simrén M, Tillisch K, Olden K, Whorwell PJ
Gastroenterology. 2016;150(6):1408-1419
DOI: [10.1053/j.gastro.2016.02.034](https://doi.org/10.1053/j.gastro.2016.02.034)

## Worked example

### All seven required flags

Given: `continuous_or_nearly_continuous_abdominal_pain=true, fulfilled_last_3_months=true, no_or_only_occasional_relationship_with_physiological_events=true, not_explained_by_another_gi_or_medical_condition=true, onset_at_least_6_months=true, pain_limits_daily_functioning=true, pain_not_feigned=true`

1. Continuous or nearly continuous abdominal pain is true
2. No or only occasional relationship with eating, defecation, or menses is true
3. Pain limits daily functioning is true
4. Pain is not feigned
5. Pain is not explained by another GI or medical condition
6. Criteria fulfilled for the last 3 months and onset at least 6 months prior are true
7. rome_iv_caps is true


### Six required flags without 6-month onset

Given: `continuous_or_nearly_continuous_abdominal_pain=true, fulfilled_last_3_months=true, no_or_only_occasional_relationship_with_physiological_events=true, not_explained_by_another_gi_or_medical_condition=true, onset_at_least_6_months=false, pain_limits_daily_functioning=true, pain_not_feigned=true`

1. Six required flags hold
2. Onset at least 6 months prior is false
3. rome_iv_caps is false


## Also searched as

- Rome IV CAPS
- Rome IV centrally mediated abdominal pain syndrome
- Keefer 2016 CAPS
- centrally mediated abdominal pain
- functional abdominal pain syndrome
- Rome IV FAPS
- Rome IV D1 CAPS
- CAPS diagnostic criteria

## Parameters

- `continuous_or_nearly_continuous_abdominal_pain` (boolean, required): Continuous or nearly continuous abdominal pain, as assigned (Keefer 2016 Rome IV CAPS / D1). true or false as assigned by the caller. magent does not examine the patient.
- `no_or_only_occasional_relationship_with_physiological_events` (boolean, required): No or only occasional relationship of pain with physiological events (eating, defecation, or menses), as assigned (Keefer 2016). true or false as assigned by the caller. magent does not examine the patient.
- `pain_limits_daily_functioning` (boolean, required): Pain limits some aspect of daily functioning, as assigned (Keefer 2016). true or false as assigned by the caller. magent does not examine the patient.
- `pain_not_feigned` (boolean, required): The pain is not feigned, as assigned by the caller (Keefer 2016). true or false as assigned by the caller. magent does not judge feigning beyond this flag.
- `not_explained_by_another_gi_or_medical_condition` (boolean, required): Pain is not explained by another structural or functional gastrointestinal disorder or other medical condition, as assigned (Keefer 2016). true or false as assigned by the caller. magent does not examine the patient.
- `fulfilled_last_3_months` (boolean, required): Criteria fulfilled for the last 3 months, as assigned (Keefer 2016). true or false as assigned by the caller. magent does not take a history.
- `onset_at_least_6_months` (boolean, required): Symptom onset at least 6 months prior to diagnosis, as assigned (Keefer 2016). true or false as assigned by the caller. magent does not take a history.

## 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/rome_iv_caps`
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": [
    {
      "continuous_or_nearly_continuous_abdominal_pain": "true",
      "fulfilled_last_3_months": "true",
      "no_or_only_occasional_relationship_with_physiological_events": "true",
      "not_explained_by_another_gi_or_medical_condition": "true",
      "onset_at_least_6_months": "true",
      "pain_limits_daily_functioning": "true",
      "pain_not_feigned": "true"
    },
    {
      "continuous_or_nearly_continuous_abdominal_pain": "true",
      "fulfilled_last_3_months": "true",
      "no_or_only_occasional_relationship_with_physiological_events": "true",
      "not_explained_by_another_gi_or_medical_condition": "true",
      "onset_at_least_6_months": "true",
      "pain_limits_daily_functioning": "true",
      "pain_not_feigned": "true"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/rome_iv_caps",
  "items": [
    {
      "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": "Keefer L, Drossman DA, Guthrie E, Simrén M, Tillisch K, Olden K, Whorwell PJ",
        "doi": "10.1053/j.gastro.2016.02.034",
        "id": "keefer-2016",
        "pmid": "27144628",
        "source": "Gastroenterology. 2016;150(6):1408-1419",
        "title": "Centrally Mediated Disorders of Gastrointestinal Pain"
      },
      "formula": "rome_iv_caps",
      "formula_expression": "rome_iv_caps iff continuous_or_nearly_continuous_abdominal_pain and no_or_only_occasional_relationship_with_physiological_events and pain_limits_daily_functioning and pain_not_feigned and not_explained_by_another_gi_or_medical_condition and fulfilled_last_3_months and onset_at_least_6_months (Keefer 2016 Rome IV CAPS / D1)",
      "criteria": [
        {
          "factor": "continuous_or_nearly_continuous_abdominal_pain",
          "met": true
        },
        {
          "factor": "no_or_only_occasional_relationship_with_physiological_events",
          "met": true
        },
        {
          "factor": "pain_limits_daily_functioning",
          "met": true
        },
        {
          "factor": "pain_not_feigned",
          "met": true
        },
        {
          "factor": "not_explained_by_another_gi_or_medical_condition",
          "met": true
        },
        {
          "factor": "fulfilled_last_3_months",
          "met": true
        },
        {
          "factor": "onset_at_least_6_months",
          "met": true
        }
      ],
      "rome_iv_caps": 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": "Keefer L, Drossman DA, Guthrie E, Simrén M, Tillisch K, Olden K, Whorwell PJ",
        "doi": "10.1053/j.gastro.2016.02.034",
        "id": "keefer-2016",
        "pmid": "27144628",
        "source": "Gastroenterology. 2016;150(6):1408-1419",
        "title": "Centrally Mediated Disorders of Gastrointestinal Pain"
      },
      "formula": "rome_iv_caps",
      "formula_expression": "rome_iv_caps iff continuous_or_nearly_continuous_abdominal_pain and no_or_only_occasional_relationship_with_physiological_events and pain_limits_daily_functioning and pain_not_feigned and not_explained_by_another_gi_or_medical_condition and fulfilled_last_3_months and onset_at_least_6_months (Keefer 2016 Rome IV CAPS / D1)",
      "criteria": [
        {
          "factor": "continuous_or_nearly_continuous_abdominal_pain",
          "met": true
        },
        {
          "factor": "no_or_only_occasional_relationship_with_physiological_events",
          "met": true
        },
        {
          "factor": "pain_limits_daily_functioning",
          "met": true
        },
        {
          "factor": "pain_not_feigned",
          "met": true
        },
        {
          "factor": "not_explained_by_another_gi_or_medical_condition",
          "met": true
        },
        {
          "factor": "fulfilled_last_3_months",
          "met": true
        },
        {
          "factor": "onset_at_least_6_months",
          "met": true
        }
      ],
      "rome_iv_caps": true
    }
  ]
}
```

## Response fields

- `formula` (string): rome_iv_caps
- `formula_expression` (string): Keefer 2016 Rome IV CAPS / D1: continuous or nearly continuous abdominal pain, no or only occasional relationship with eating, defecation, or menses, pain limits daily functioning, pain is not feigned, not explained by another GI or medical condition, last-3-months criteria, and 6-month onset
- `rome_iv_caps` (boolean): true only when all seven required flags hold. Not a diagnosis.
- `criteria` (array): Per-factor rows with factor and met for the seven required flags
- `citation` (object): Keefer 2016 Gastroenterology citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "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": "Keefer L, Drossman DA, Guthrie E, Simrén M, Tillisch K, Olden K, Whorwell PJ",
    "doi": "10.1053/j.gastro.2016.02.034",
    "id": "keefer-2016",
    "pmid": "27144628",
    "source": "Gastroenterology. 2016;150(6):1408-1419",
    "title": "Centrally Mediated Disorders of Gastrointestinal Pain"
  },
  "formula": "rome_iv_caps",
  "formula_expression": "rome_iv_caps iff continuous_or_nearly_continuous_abdominal_pain and no_or_only_occasional_relationship_with_physiological_events and pain_limits_daily_functioning and pain_not_feigned and not_explained_by_another_gi_or_medical_condition and fulfilled_last_3_months and onset_at_least_6_months (Keefer 2016 Rome IV CAPS / D1)",
  "criteria": [
    {
      "factor": "continuous_or_nearly_continuous_abdominal_pain",
      "met": true
    },
    {
      "factor": "no_or_only_occasional_relationship_with_physiological_events",
      "met": true
    },
    {
      "factor": "pain_limits_daily_functioning",
      "met": true
    },
    {
      "factor": "pain_not_feigned",
      "met": true
    },
    {
      "factor": "not_explained_by_another_gi_or_medical_condition",
      "met": true
    },
    {
      "factor": "fulfilled_last_3_months",
      "met": true
    },
    {
      "factor": "onset_at_least_6_months",
      "met": true
    }
  ],
  "rome_iv_caps": true
}
```

## Errors

- HTTP 400 `invalid_rome_iv_caps`: Rome IV CAPS needs the Keefer 2016 centrally mediated abdominal pain flags. Returned before settlement; you are not charged.
- HTTP 400 `invalid_flag`: boolean clinical flags must be true or false 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

- [Rome IV IBS](https://magentlab.com/docs/rome-iv-ibs) — Apply the Mearin 2016 Rome IV IBS diagnostic criteria and return supporting_features_met (0-3) and whether the published IBS box holds (rome_iv_ibs).
- [Rome IV FD](https://magentlab.com/docs/rome-iv-fd) — Apply the Stanghellini 2016 Rome IV B1 functional dyspepsia criteria and return whether PDS (B1a), EPS (B1b), and the published FD box hold (rome_iv_fd).

## 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.