Nutrition Calc

{
  "asOf": "2026-10-11T05:19:25.441Z",
  "consistency": {
    "caloriesFromMacrosPer100g": 533,
    "labelKcalPer100g": 539,
    "withinTolerance": true
  },
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "energyShare": {
    "carbsPct": 43.1,
    "fatPct": 5.2,
    "proteinPct": 4.7
  },
  "notChecked": [
    "added sugars (percent daily value for added sugars needs the added-sugar figure, not total sugars, so it is not computed)",
    "vitamins and minerals",
    "…2 more"
  ],
  "perServing": {
    "carbsG": 17.3,
    "fatG": 9.3,
    "fiberG": null,
    "kcal": 162,
    "proteinG": 1.9,
    "satFatG": 3.2,
    "sodiumMg": 12,
    "sugarsG": 16.9
  },
  "percentDailyValue": {
    "carbs": 6.3,
    "fat": 11.9,
    "fiber": null,
    "kcal": 8.1,
    "protein": 3.8,
    "satFat": 15.9,
    "sodium": 0.5
  },
  "reasons": [
    "No flags."
  ],
  "servingGrams": 30,
  "source": "computed locally",
  "summary": "30 g serving: 162 kcal (8.1% of 2,000), fat 9.3 g, carbs 17.3 g, protein 1.9 g.",
  "verdict": "CALCULATED"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://food-barcode.x402tookit.com/nutrition-calc?carbs=57.5&fat=30.9&kcal=539&protein=6.3&sat_fat=10.6&serving_g=30&sodium_mg=41&sugars=56.3'

# 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 - 'https://food-barcode.x402tookit.com/nutrition-calc?carbs=57.5&fat=30.9&kcal=539&protein=6.3&sat_fat=10.6&serving_g=30&sodium_mg=41&sugars=56.3' \
  | 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 $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
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 $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Ffood-barcode.x402tookit.com%2Fnutrition-calc
const res = await pay("https://food-barcode.x402tookit.com/nutrition-calc?carbs=57.5&fat=30.9&kcal=539&protein=6.3&sat_fat=10.6&serving_g=30&sodium_mg=41&sugars=56.3");
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 $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://food-barcode.x402tookit.com/nutrition-calc?carbs=57.5&fat=30.9&kcal=539&protein=6.3&sat_fat=10.6&serving_g=30&sodium_mg=41&sugars=56.3")
    print(res.status_code, res.text)