# magent Rome IV C3 Functional Diarrhea Calculator

> magent Rome IV C3 Functional Diarrhea Calculator is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Evaluates whether a patient meets Rome IV C3 criteria for functional diarrhea based on three caller-assigned boolean flags

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/rome_iv_diarrhea
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/magent-rome-iv-c3-functional-diarrhea-calculator-e5c9cae1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sNMJChy3aSxUrpUP6uST2

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability magent-rome-iv-c3-functional-diarrhea-calculator-e5c9cae1
```

Example prompt: Check if this adult patient meets Rome IV C3 functional diarrhea criteria: the last-3-months with 6-month onset criteria is met (true), loose or watery stools without predominant pain or bloating in more than 25% of stools is true, and the patient does not meet IBS-D criteria (true).

## When to prefer this

Use this endpoint when you have already gathered the three Rome IV C3 boolean flags from a clinician or structured clinical data and need to programmatically determine whether the patient meets functional diarrhea criteria per Mearin 2016. Prefer this over manual logic when automating GI clinical documentation, decision support pipelines, or research data pipelines for adult patients. Do not use for pediatric patients (Rome IV G5), IBS-D classification, functional constipation, or Manning criteria.

## Known failure modes

- Missing any of the three required boolean query parameters returns a validation error
- Non-boolean values for any flag cause a schema error
- Endpoint is for adults only (C3); applying to pediatric patients (G5) is a misuse not caught by the API
- If the caller has not properly excluded IBS-D before setting the flag, the output may be clinically misleading
- Network or payment authorization failures (x402) return HTTP 402

## How this service works

Mearin 2016 Rome IV C3 functional diarrhea. rome_iv_diarrhea is true iff last-3-months criteria with 6-month onset, loose or watery stools without predominant abdominal pain or bothersome bloating in >25% of stools, and insufficient criteria for diarrhea-predominant IBS. Caller assigns three flags. magent does not examine the patient. Not a diagnosis. Adult C3 only. Not child G5, not IBS-D, not Rome IV IBS, not Manning, not functional constipation.

## Output

Returns a boolean (rome_iv_diarrhea) indicating whether all three Rome IV C3 criteria are simultaneously satisfied: (1) last-3-months symptom duration with 6-month onset, (2) loose or watery stools without predominant abdominal pain or bloating in >25% of stools, and (3) insufficient criteria for IBS-D. This is a classification aid, not a clinical diagnosis.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "criteria_last_3_months_onset_6_months",
      "loose_or_watery_stools_gt_25_percent_without_predominant_pain_or_bloating",
      "insufficient_criteria_for_ibs_d"
     ],
     "properties": {
      "insufficient_criteria_for_ibs_d": {
       "type": "boolean",
       "description": "Insufficient criteria for diarrhea-predominant IBS, as assigned by the caller (Mearin 2016 C3 excludes patients who meet IBS-D). true or false. magent does not apply the IBS box."
      },
      "criteria_last_3_months_onset_6_months": {
       "type": "boolean",
       "description": "Criteria fulfilled for the last 3 months with symptom onset at least 6 months prior to diagnosis, as assigned (Mearin 2016 C3). true or false as assigned by the caller. magent does not take a history."
      },
      "loose_or_watery_stools_gt_25_percent_without_predominant_pain_or_bloating": {
       "type": "boolean",
       "description": "Loose or watery stools, without predominant abdominal pain or bothersome bloating, occurring in more than 25% of stools (Mearin 2016 C3). true or false as assigned by the caller. magent does not inspect stool."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/magent-rome-iv-c3-functional-diarrhea-calculator-e5c9cae1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)