# magent Rome IV CHS Calculator

> magent Rome IV CHS 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 the Rome IV (Stanghellini 2016) diagnostic criteria for Cannabinoid Hyperemesis Syndrome (CHS) based on six caller-assigned boolean flags

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/rome_iv_chs
- 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-chs-calculator-f1b0dfc2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ouirqY_0q7N22t5FicC0w

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-chs-calculator-f1b0dfc2
```

Example prompt: Does this patient meet Rome IV criteria for cannabinoid hyperemesis syndrome? They have stereotypical episodic vomiting resembling CVS, presentation after prolonged excessive cannabis use, vomiting relieved by sustained cannabis cessation, criteria fulfilled for the last 3 months, onset at least 6 months ago, and they do exhibit pathologic bathing behavior.

## When to prefer this

Use this endpoint when you need a fast, structured, rule-based evaluation of Rome IV Cannabinoid Hyperemesis Syndrome criteria per Stanghellini 2016, and all six required criteria have already been assessed by a clinician or algorithm and can be expressed as boolean flags. Prefer this over general LLM reasoning when you need an auditable, reproducible, criterion-by-criterion CHS classification. Not suitable when a cannabis history has not yet been taken or when criteria assignment is uncertain.

## Known failure modes

- Missing any of the six required boolean query parameters returns a validation error
- Incorrect types (non-boolean values) for query parameters cause request failure
- Network or server errors return HTTP 5xx with no result
- Ambiguous clinical history not expressible as boolean flags must be resolved by the caller before calling

## How this service works

Stanghellini 2016 Rome IV CHS. rome_iv_chs is true iff stereotypical episodic vomiting resembling CVS, presentation after prolonged excessive cannabis use, relief with sustained cannabis cessation, criteria fulfilled for the last 3 months, and onset at least 6 months prior. pathologic_bathing is supportive and not required. Caller assigns six flags. magent does not take a cannabis history. Not a diagnosis, not cyclic vomiting syndrome.

## Output

Returns a boolean field rome_iv_chs indicating whether all required Rome IV Cannabinoid Hyperemesis Syndrome criteria (Stanghellini 2016) are met: stereotypical episodic vomiting resembling CVS, presentation after prolonged excessive cannabis use, relief with sustained cannabis cessation, criteria fulfilled for the last 3 months, and symptom onset at least 6 months prior. The pathologic_bathing flag is supportive and not required. This is not a 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": [
      "stereotypical_episodic_vomiting",
      "after_prolonged_excessive_cannabis",
      "relief_with_sustained_cessation",
      "fulfilled_last_3_months",
      "onset_at_least_6_months",
      "pathologic_bathing"
     ],
     "properties": {
      "pathologic_bathing": {
       "type": "boolean",
       "description": "Pathologic bathing behavior (prolonged hot baths or showers), a supportive criterion that is not required for rome_iv_chs (Stanghellini 2016). true or false as assigned by the caller. magent does not examine the patient."
      },
      "fulfilled_last_3_months": {
       "type": "boolean",
       "description": "Criteria fulfilled for the last 3 months, as assigned (Stanghellini 2016). true or false as assigned by the caller. magent does not take a history."
      },
      "onset_at_least_6_months": {
       "type": "boolean",
       "description": "Symptom onset at least 6 months prior to diagnosis, as assigned (Stanghellini 2016). true or false as assigned by the caller. magent does not take a history."
      },
      "relief_with_sustained_cessation": {
       "type": "boolean",
       "description": "Relief of vomiting episodes by sustained cessation of cannabis, as assigned (Stanghellini 2016). true or false as assigned by the caller. magent does not take a cannabis history."
      },
      "stereotypical_episodic_vomiting": {
       "type": "boolean",
       "description": "Stereotypical episodic vomiting resembling cyclic vomiting syndrome (CVS) in onset, duration, and frequency (Stanghellini 2016). true or false as assigned by the caller. magent does not examine the patient."
      },
      "after_prolonged_excessive_cannabis": {
       "type": "boolean",
       "description": "Presentation after prolonged excessive cannabis use, as assigned (Stanghellini 2016). true or false as assigned by the caller. magent does not take a cannabis history."
      }
     }
    }
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/magent-rome-iv-chs-calculator-f1b0dfc2/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)