76trust / 100

Jp Payslip Audit

by Mart402 in Security & trust

x402 APIPassing, checked 3 h ago

Japan payslip audit: recompute statutory premiums and withholding tax from official tables and diff against the actual amounts. Per-item verdicts (match/explainable/mismatch) that explain grade revisions and combined care-premium notation instead of crying wolf. $0.02/call.

POST
https://mart402.com/v1/jp-payslip-audit
Price
$0.02
per call in USDC
Uptime
95.8%
last 30 days
Response time
404 ms
501 ms slowest 5%
Last check
Passed
3 h ago, next any minute now

Run a free test callHow to call it

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Status and outage history · Atom feed

How to call it

POST https://mart402.com/v1/jp-payslip-audit

Each call costs $0.02 in USDC on Base, paid with the request over x402.

Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.

Example request

From the listing.

POST https://mart402.com/v1/jp-payslip-audit
content-type: application/json

{
  "age": 35,
  "payslip": {
    "dependents": 1,
    "health_yen": 14775,
    "income_tax_yen": 4380,
    "monthly_gross_yen": 300000,
    "pension_yen": 27450
  },
  "prefecture": "tokyo"
}

Parameters

ParameterTypeRequiredDescription
agenumberNo
payslipobjectNo
prefecturestringNo

Example response

The provider's example. We can't check it without paying.

Example response, 95 lines
{
  "as_of": "2026-08-21",
  "assumptions": [
    "電算特例と紙の税額表の差は1000円まで適法差として扱う(実測ベースの目安)。非課税通勤手当の上限判定(月15万円等)は行わない"
  ],
  "billable": true,
  "breakdown": [],
  "carried_forward": [],
  "disclaimer": "仮定条件に基づく概算試算。税務相談・手続代行・法律相談ではない。申告・届出への使用不可。確定額は官公署または税理士・社会保険労務士等に確認のこと。",
  "not_covered": [
    "labor insurance の業種別特例(建設・農林以外)",
    "乙欄・丙欄",
    "住民税額の妥当性",
    "健康保険組合(協会けんぽ以外)",
    "厚生年金基金・企業年金",
    "国民健康保険・国民年金",
    "年の中途の年末調整",
    "従たる給与",
    "日額表",
    "産休育休免除・随時改定(月変)・定時決定の細目",
    "財形・組合費等の協定控除",
    "賞与明細(jp-bonus-netを使うこと)",
    "通勤手当の非課税限度額判定"
  ],
  "note": "SAMPLE RESPONSE generated by the exact deterministic engine that serves production (jp-statutory has no LLM: same input always produces this byte-identical result, carrying the same rules_version and cited primary sources). Served free at /samples/{product} so you can verify the response shape, the rules_version field and the source citations before paying. No payment was taken. The sample_input shown is the catalog example input that produced this output.",
  "ok": true,
  "result": {
    "consistent": true,
    "counts": {
      "explainable": 1,
      "match": 2,
      "not_provided": 2
    },
    "items": [
      {
        "actual_yen": 14775,
        "diff_yen": 0,
        "expected_yen": 14775,
        "item": "health",
        "verdict": "match"
      },
      {
        "actual_yen": null,
        "expected_yen": 0,
        "item": "long_term_care",
        "verdict": "not_provided"
      },
      {
        "actual_yen": 27450,
        "diff_yen": 0,
        "expected_yen": 27450,
        "item": "pension",
        "verdict": "match"
      },
      {
        "actual_yen": null,
        "expected_yen": 1500,
        "item": "employment_insurance",
        "verdict": "not_provided"
      },
      {
        "actual_yen": 4380,
        "diff_yen": -410,
        "expected_yen": 4790,
        "explanation": "紙の税額表(月額表)方式と電算特例方式の適法な差の範囲内",
        "item": "income_tax_withheld",
        "verdict": "explainable"
      }
    ],
    "smr_basis": "estimated_from_gross",
    "summary_line": "監査3項目: 一致2・説明可能1・不一致0 -> 計算整合",
    "withholding_base_yen": 257775
  },
  "rules_version": "2026.08.18",
  "sample": true,
  "sample_input": {
    "age": 35,
    "payslip": {
      "dependents": 1,
      "health_yen": 14775,
      "income_tax_yen": 4380,
      "monthly_gross_yen": 300000,
      "pension_yen": 27450
    },
    "prefecture": "tokyo"
  },
  "sources": [
    "engine-composition",
    "https://www.kyoukaikenpo.or.jp/assets/R8_13tokyo.pdf",
    "https://www.nta.go.jp/publication/pamph/gensen/zeigakuhyo2026/data/17-18.pdf"
  ],
  "summary": "監査3項目: 一致2・説明可能1・不一致0 -> 計算整合",
  "tool": "jp-payslip-audit",
  "unverified_rules": []
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.02.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://mart402.com/v1/jp-payslip-audit' \
  -H 'content-type: application/json' \
  --data-raw '{"age":35,"payslip":{"dependents":1,"health_yen":14775,"income_tax_yen":4380,"monthly_gross_yen":300000,"pension_yen":27450},"prefecture":"tokyo"}'

# 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://mart402.com/v1/jp-payslip-audit' \
  -H 'content-type: application/json' \
  --data-raw '{"age":35,"payslip":{"dependents":1,"health_yen":14775,"income_tax_yen":4380,"monthly_gross_yen":300000,"pension_yen":27450},"prefecture":"tokyo"}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: pay and call
// 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%2Fmart402.com%2Fv1%2Fjp-payslip-audit&method=POST
const res = await pay("https://mart402.com/v1/jp-payslip-audit", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "age": 35,
    "payslip": {
      "dependents": 1,
      "health_yen": 14775,
      "income_tax_yen": 4380,
      "monthly_gross_yen": 300000,
      "pension_yen": 27450
    },
    "prefecture": "tokyo"
  }),
});
console.log(res.status, await res.text());
Python: pay and call
# 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.post(
        "https://mart402.com/v1/jp-payslip-audit",
        json={
            "age": 35,
            "payslip": {
                "dependents": 1,
                "health_yen": 14775,
                "income_tax_yen": 4380,
                "monthly_gross_yen": 300000,
                "pension_yen": 27450,
            },
            "prefecture": "tokyo",
        },
    )
    print(res.status_code, res.text)

Security scan

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