# RIFLE criteria

RIFLE

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

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

## What it computes

Apply Bellomo 2004 Fig. 1 RIFLE classification and return the worse of the creatinine and urine-output limbs (none, risk, injury, failure), with persistent ARF beyond 4 weeks mapping to loss and ESRD beyond 3 months mapping to esrd.

## When to use

When an agent already has baseline and current serum creatinine in mg/dL, a caller-assigned RIFLE urine-output category, and optional Loss/ESRD duration flags, and needs the published RIFLE class. magent does not assay creatinine or measure urine. Not AKIN 2007 and not KDIGO 2012.

## When not to use

- Not a medical device and not a diagnosis of acute kidney injury.
- magent does not assay creatinine or measure urine. baseline_creatinine_mg_dl and current_creatinine_mg_dl are caller-supplied in mg/dL only.
- urine_output is the caller-assigned published duration category. magent does not collect weight or urine volume.
- Loss and ESRD are caller-assigned duration flags; magent does not collect observation time.
- This tool is Bellomo 2004 Fig. 1 RIFLE classification only. Not AKIN 2007 and not KDIGO 2012. It does not estimate baseline creatinine with MDRD.

## Formula

```
RIFLE class = esrd if ESRD >3 months, else loss if persistent ARF >4 weeks, else worse of creatinine vs urine (none < risk < injury < failure). Creatinine vs baseline (unrounded mg/dL): Failure if ratio ≥3.0 or (current ≥4.0 mg/dL and increase ≥0.5 mg/dL); Injury if ratio ≥2.0; Risk if ratio ≥1.5. GFR % decrease (Risk >25%, Injury >50%, Failure >75%) is equivalent to those creatinine multiples. Urine (caller-assigned): none → none; oliguria_gt_6h → Risk; oliguria_gt_12h → Injury; oliguria_24h_or_anuria_12h → Failure (Bellomo 2004 Fig. 1)
```

## Citation

[Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group](https://doi.org/10.1186/cc2872)
Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P, and the ADQI workgroup
Crit Care. 2004;8(4):R204-R212
DOI: [10.1186/cc2872](https://doi.org/10.1186/cc2872)

## Worked example

### No RIFLE class: creatinine unchanged, no oliguria, no Loss or ESRD

Given: `baseline_creatinine_mg_dl=1.0, current_creatinine_mg_dl=1.0, esrd_gt_3_months=false, persistent_arf_gt_4_weeks=false, urine_output=none`

1. baseline 1.0 mg/dL and current 1.0 mg/dL: increase 0, ratio 1.0 → creat_class none
2. urine_output none → uo_class none
3. persistent_arf_gt_4_weeks false and esrd_gt_3_months false → rifle_class = worse(none, none) = none


## Also searched as

- RIFLE
- RIFLE criteria
- RIFLE classification
- ADQI RIFLE
- Bellomo 2004 RIFLE
- RIFLE Risk Injury Failure
- RIFLE urine output
- acute renal failure RIFLE

## Parameters

- `baseline_creatinine_mg_dl` (number, required): Baseline serum creatinine in mg/dL (0.1-20). Classification uses the unrounded value. µmol/L is not accepted on this tool. magent does not assay creatinine.
- `current_creatinine_mg_dl` (number, required): Current serum creatinine in mg/dL (0.1-20). Classification uses the unrounded value. µmol/L is not accepted on this tool. magent does not assay creatinine.
- `urine_output` (string, required): Caller-assigned RIFLE urine-output category (Bellomo 2004 Fig. 1): none (no oliguria or anuria criterion); oliguria_gt_6h (<0.5 mL/kg/h for 6 hours); oliguria_gt_12h (<0.5 mL/kg/h for 12 hours); oliguria_24h_or_anuria_12h (<0.3 mL/kg/h for 24 hours or anuria for 12 hours). Case-insensitive. magent does not collect weight or measure urine.
- `persistent_arf_gt_4_weeks` (boolean, required): Persistent complete loss of kidney function for more than 4 weeks as assigned by the caller (Bellomo 2004 Loss). true maps to rifle_class loss unless esrd_gt_3_months is true. true or false.
- `esrd_gt_3_months` (boolean, required): End-stage kidney disease for more than 3 months as assigned by the caller (Bellomo 2004 ESRD). true maps to rifle_class esrd irrespective of creatinine, urine, or Loss. true or false.

## 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/rifle`
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": [
    {
      "baseline_creatinine_mg_dl": "1.0",
      "current_creatinine_mg_dl": "1.0",
      "esrd_gt_3_months": "false",
      "persistent_arf_gt_4_weeks": "false",
      "urine_output": "none"
    },
    {
      "baseline_creatinine_mg_dl": "1.0",
      "current_creatinine_mg_dl": "1.0",
      "esrd_gt_3_months": "false",
      "persistent_arf_gt_4_weeks": "false",
      "urine_output": "none"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/rifle",
  "items": [
    {
      "components": [
        {
          "value": "none",
          "factor": "creat_class",
          "met": false
        },
        {
          "value": "none",
          "factor": "uo_class",
          "met": false
        }
      ],
      "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": "Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P, and the ADQI workgroup",
        "doi": "10.1186/cc2872",
        "id": "bellomo-2004",
        "pmid": "15312219",
        "source": "Crit Care. 2004;8(4):R204-R212",
        "title": "Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group"
      },
      "formula": "rifle",
      "formula_expression": "RIFLE class = esrd if ESRD >3 months, else loss if persistent ARF >4 weeks, else worse of creatinine vs urine (none < risk < injury < failure). Creatinine vs baseline (unrounded mg/dL): Failure if ratio ≥3.0 or (current ≥4.0 mg/dL and increase ≥0.5 mg/dL); Injury if ratio ≥2.0; Risk if ratio ≥1.5. GFR % decrease (Risk >25%, Injury >50%, Failure >75%) is equivalent to those creatinine multiples. Urine (caller-assigned): none → none; oliguria_gt_6h → Risk; oliguria_gt_12h → Injury; oliguria_24h_or_anuria_12h → Failure (Bellomo 2004 Fig. 1)",
      "baseline_creatinine_mg_dl": 1.0,
      "current_creatinine_mg_dl": 1.0,
      "urine_output": "none",
      "creat_class": "none",
      "esrd_gt_3_months": false,
      "persistent_arf_gt_4_weeks": false,
      "rifle_class": "none",
      "uo_class": "none"
    },
    {
      "components": [
        {
          "value": "none",
          "factor": "creat_class",
          "met": false
        },
        {
          "value": "none",
          "factor": "uo_class",
          "met": false
        }
      ],
      "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": "Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P, and the ADQI workgroup",
        "doi": "10.1186/cc2872",
        "id": "bellomo-2004",
        "pmid": "15312219",
        "source": "Crit Care. 2004;8(4):R204-R212",
        "title": "Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group"
      },
      "formula": "rifle",
      "formula_expression": "RIFLE class = esrd if ESRD >3 months, else loss if persistent ARF >4 weeks, else worse of creatinine vs urine (none < risk < injury < failure). Creatinine vs baseline (unrounded mg/dL): Failure if ratio ≥3.0 or (current ≥4.0 mg/dL and increase ≥0.5 mg/dL); Injury if ratio ≥2.0; Risk if ratio ≥1.5. GFR % decrease (Risk >25%, Injury >50%, Failure >75%) is equivalent to those creatinine multiples. Urine (caller-assigned): none → none; oliguria_gt_6h → Risk; oliguria_gt_12h → Injury; oliguria_24h_or_anuria_12h → Failure (Bellomo 2004 Fig. 1)",
      "baseline_creatinine_mg_dl": 1.0,
      "current_creatinine_mg_dl": 1.0,
      "urine_output": "none",
      "creat_class": "none",
      "esrd_gt_3_months": false,
      "persistent_arf_gt_4_weeks": false,
      "rifle_class": "none",
      "uo_class": "none"
    }
  ]
}
```

## Response fields

- `formula` (string): rifle
- `formula_expression` (string): Published Bellomo 2004 Fig. 1 RIFLE classification rule
- `baseline_creatinine_mg_dl` (number): Echo of baseline creatinine in mg/dL
- `current_creatinine_mg_dl` (number): Echo of current creatinine in mg/dL
- `urine_output` (string): Canonical urine-output token: none, oliguria_gt_6h, oliguria_gt_12h, or oliguria_24h_or_anuria_12h
- `persistent_arf_gt_4_weeks` (boolean): Echo of the caller-assigned persistent ARF >4 weeks flag
- `esrd_gt_3_months` (boolean): Echo of the caller-assigned ESRD >3 months flag
- `creat_class` (string): RIFLE creatinine limb class: none, risk, injury, or failure (before Loss/ESRD)
- `uo_class` (string): RIFLE urine-output limb class: none, risk, injury, or failure (before Loss/ESRD)
- `rifle_class` (string): Final RIFLE class: esrd if esrd_gt_3_months, else loss if persistent_arf_gt_4_weeks, else the worse of creat_class and uo_class (none, risk, injury, or failure). Not a diagnosis.
- `components` (array): Rows for creat_class and uo_class with factor, met, and value (the limb class)
- `citation` (object): Bellomo 2004 Crit Care citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "value": "none",
      "factor": "creat_class",
      "met": false
    },
    {
      "value": "none",
      "factor": "uo_class",
      "met": false
    }
  ],
  "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": "Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P, and the ADQI workgroup",
    "doi": "10.1186/cc2872",
    "id": "bellomo-2004",
    "pmid": "15312219",
    "source": "Crit Care. 2004;8(4):R204-R212",
    "title": "Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group"
  },
  "formula": "rifle",
  "formula_expression": "RIFLE class = esrd if ESRD >3 months, else loss if persistent ARF >4 weeks, else worse of creatinine vs urine (none < risk < injury < failure). Creatinine vs baseline (unrounded mg/dL): Failure if ratio ≥3.0 or (current ≥4.0 mg/dL and increase ≥0.5 mg/dL); Injury if ratio ≥2.0; Risk if ratio ≥1.5. GFR % decrease (Risk >25%, Injury >50%, Failure >75%) is equivalent to those creatinine multiples. Urine (caller-assigned): none → none; oliguria_gt_6h → Risk; oliguria_gt_12h → Injury; oliguria_24h_or_anuria_12h → Failure (Bellomo 2004 Fig. 1)",
  "baseline_creatinine_mg_dl": 1.0,
  "current_creatinine_mg_dl": 1.0,
  "urine_output": "none",
  "creat_class": "none",
  "esrd_gt_3_months": false,
  "persistent_arf_gt_4_weeks": false,
  "rifle_class": "none",
  "uo_class": "none"
}
```

## Errors

- HTTP 400 `invalid_creatinine`: creatinine_mg_dl (0.1-20) or creatinine_umol_l (9-1768) is required Returned before settlement; you are not charged.
- HTTP 400 `invalid_rifle_urine`: urine_output must be none, oliguria_gt_6h, oliguria_gt_12h, or oliguria_24h_or_anuria_12h (Bellomo 2004). 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

- [AKIN](https://magentlab.com/docs/akin) — Apply Mehta 2007 Table 2 AKIN staging and return stage 0-3 as the worse of the creatinine and urine-output limbs, with initiated renal replacement therapy mapping to stage 3.
- [CKD-EPI 2021 eGFR](https://magentlab.com/docs/egfr) — Compute race-free CKD-EPI 2021 creatinine eGFR in mL/min/1.73m2.

## 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.