---
title: "Section 301 China lists: headings, rates, dates, counts (pay per call in USDC via x402, no key)"
method: POST
path: "/x402/api/section301"
tags: ["Dutyfinch"]
---

# Section 301 China lists: headings, rates, dates, counts (pay per call in USDC via x402, no key)

`POST /x402/api/section301`

## Request

- Base URL: `https://dutyfinch.cybermaxtools.com`
- URL: `https://dutyfinch.cybermaxtools.com/x402/api/section301`
- Auth: none required

Every Section 301 heading in Chapter 99 (lists 1, 2, 3, 4A, 4B, the 2024 four-year-review increases and the exclusion headings) with the official rate text, effective dates and how many codes each covers.

Pay per call with x402: $0.012 per call in USDC on Base. No key, no account: an unpaid call returns 402 with the payment requirements; retry with the X-PAYMENT (x402 v1) or PAYMENT-SIGNATURE (v2) header.

## Request body

- object

## Response `200`

Results (same field names as the bulk version's dataset records) plus the free-tier limits.

- object

## Other responses

- `400`: Invalid input
- `401`: Invalid or revoked API key
- `402`: Payment Required: x402 payment requirements (body: x402Version 1 accepts[]; header PAYMENT-REQUIRED: x402 v2).
- `504`: Took too long; ask for fewer items

---

[API](https://skmtc.dev/cybermaxtools/apis/dutyfinch-api.md) · [All operations](https://skmtc.dev/cybermaxtools/apis/dutyfinch-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cybermaxtools/apis/dutyfinch-api/revisions/e333c51ba697?raw)