Calc Stool Osmotic Gap

{
  "count": 2,
  "items": [
    {
      "assumed_osmolality": true,
      "citation": {
        "authors": "Eherer AJ, Fordtran JS",
        "doi": "10.1016/0016-5085(92)90845-P",
        "id": "eherer-fordtran-1992",
        "source": "Gastroenterology. 1992;103(2):545-551",
        "title": "Fecal osmotic gap and pH in experimental diarrhea of various causes"
      },
      "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.",
      "formula": "eherer_fordtran",
      "formula_expression": "osmotic_gap = stool_osm_mosm_kg - 2 * (stool_sodium_mmol_l + stool_potassium_mmol_l)",
      "gap_gt_50": true,
      "osmotic_gap": 80,
      "stool_osm_mosm_kg": 290,
      "stool_potassium_mmol_l": 75,
      "stool_sodium_mmol_l": 30
    },
    {
      "assumed_osmolality": true,
      "citation": {
        "authors": "Eherer AJ, Fordtran JS",
        "doi": "10.1016/0016-5085(92)90845-P",
        "id": "eherer-fordtran-1992",
        "source": "Gastroenterology. 1992;103(2):545-551",
        "title": "Fecal osmotic gap and pH in experimental diarrhea of various causes"
      },
      "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.",
      "formula": "eherer_fordtran",
      "formula_expression": "osmotic_gap = stool_osm_mosm_kg - 2 * (stool_sodium_mmol_l + stool_potassium_mmol_l)",
      "gap_gt_50": true,
      "osmotic_gap": 80,
      "stool_osm_mosm_kg": 290,
      "stool_potassium_mmol_l": 75,
      "stool_sodium_mmol_l": 30
    }
  ],
  "path": "/api/calc/stool_osmotic_gap"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.magentlab.com/api/calc/stool_osmotic_gap' \
  -H 'content-type: application/json' \
  --data-raw '{"items":[{"stool_osm_mosm_kg":290,"stool_potassium_mmol_l":75,"stool_sodium_mmol_l":30},{"stool_osm_mosm_kg":290,"stool_potassium_mmol_l":75,"stool_sodium_mmol_l":30}]}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://api.magentlab.com/api/calc/stool_osmotic_gap' \
  -H 'content-type: application/json' \
  --data-raw '{"items":[{"stool_osm_mosm_kg":290,"stool_potassium_mmol_l":75,"stool_sodium_mmol_l":30},{"stool_osm_mosm_kg":290,"stool_potassium_mmol_l":75,"stool_sodium_mmol_l":30}]}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.007 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.007" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.007 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.magentlab.com%2Fapi%2Fcalc%2Fstool_osmotic_gap&method=POST
const res = await pay("https://api.magentlab.com/api/calc/stool_osmotic_gap", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "items": [
      {
        "stool_osm_mosm_kg": 290,
        "stool_potassium_mmol_l": 75,
        "stool_sodium_mmol_l": 30
      },
      {
        "stool_osm_mosm_kg": 290,
        "stool_potassium_mmol_l": 75,
        "stool_sodium_mmol_l": 30
      }
    ]
  }),
});
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.007 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.007"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://api.magentlab.com/api/calc/stool_osmotic_gap",
        json={
            "items": [
                {
                    "stool_osm_mosm_kg": 290,
                    "stool_potassium_mmol_l": 75,
                    "stool_sodium_mmol_l": 30,
                },
                {
                    "stool_osm_mosm_kg": 290,
                    "stool_potassium_mmol_l": 75,
                    "stool_sodium_mmol_l": 30,
                },
            ],
        },
    )
    print(res.status_code, res.text)