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tariff-resolver

v1.0.2

Published

MCP server: US HTS tariff lookup, chapter-99 additional-duty rules, and landed-cost components from official USITC public-domain data. Not affiliated with any government agency.

Readme

tariff-resolver

npm version CI coverage: ≥95% lines, CI-enforced npm downloads node MCP Registry license: MIT

An MCP server that turns your AI assistant into a US import duty research tool — built on official USITC Harmonized Tariff Schedule data (US Government public domain, 35,000+ tariff lines).

  • 🔍 HTS code candidates from plain product descriptions, with CBP CROSS ruling links
  • 🧮 Landed-cost components: MFN/FTA base rates + Chapter 99 additional duties (IEEPA / Section 301 / 232) + MPF/HMF fees
  • 📡 Tariff change tracking: watchlist your HTS codes, diff rates between HTS revisions
  • 🤖 AI-optimized, hallucination-resistant: returns the actual Chapter 99 rule text with parsed rates, so your LLM reasons over real exception chains instead of inventing 2024-era numbers

Demo: resolving duties for a vacuum flask from China, then switching product and origin — the full Chapter 99 stack recalculates live

Why now: since the de minimis exemption ended (Aug 29, 2025), every US-bound shipment needs an HTS code and duty payment — and 2025–26 rates keep changing by executive order.

Not affiliated with any government agency. Outputs are candidates/estimates for pre-broker screening — not customs, legal, or tax advice. Estimates exclude AD/CVD duties.

Install

Requires Node.js ≥ 18.

claude mcp add tariff-resolver -- npx -y tariff-resolver

Or in any MCP client config:

{ "mcpServers": { "tariff-resolver": { "command": "npx", "args": ["-y", "tariff-resolver"] } } }

Claude Desktop (one-click): download tariff-resolver-<version>.mcpb from Releases and double-click it — no terminal needed.

💡 Try these prompts

  • Basic search: "Find the HTS code for a men's 100% cotton t-shirt."
  • Full scenario: "Calculate the tariff scenario for HTS 6109.10.00, origin China, customs value $5,000, ocean freight."
  • Sourcing decision: "I'm importing $10k of stainless steel vacuum flasks. Compare landed cost if I source from China vs Vietnam."
  • Stay current: "Watch tariff changes for my catalog: 6109.10.00, 8507.60.00, 9617.00.10."

Tools

| Tool | What it does | |---|---| | search_hs_candidates | Product description → top HTS candidates with rates + CBP CROSS ruling links | | calculate_tariff_scenario | HTS code + origin + value (+ weight) → structured JSON: base MFN/FTA rate, active Chapter 99 rules (footnote-linked / origin-matched / universal, terminated rules filtered), MPF/HMF | | watch_tariff_changes | Register HTS codes to a local watchlist | | check_tariff_updates | Diff current vs previous HTS revision — see exactly which rates changed | | dataset_info | Data revision date, row counts, source, license |

Design

The server does the retrieval; your LLM does the reasoning. Chapter 99 rules are returned verbatim (with parsed adder_pct where applicable) so the model reads the actual exception chains instead of trusting a black-box calculation. Rates for 10-digit statistical suffixes inherit from their parent rate line. Terminated provisions are filtered out and counted.

Data

Ships with a full HTS snapshot, fetched from USITC's official JSON API (US Government public domain). Refresh anytime:

python3 scripts/fetch_hts.py   # ~2 min, fails hard rather than write a partial dataset

dataset_info reports the revision date your queries run against.

Privacy Policy

tariff-resolver runs entirely on your machine and collects nothing:

  • Data collection: none. No queries, telemetry, analytics, or usage data are collected or transmitted.
  • Usage and storage: your watchlist is stored in a local JSON file on your machine; all lookups run against the bundled local dataset.
  • Third-party sharing: none. The server makes no network requests at runtime. (The optional scripts/fetch_hts.py refresh script contacts only the official USITC API.)
  • Data retention: nothing to retain — delete the local watchlist file at any time.
  • Contact: [email protected]

Full policy: https://opsloft.dev/privacy

License

MIT. Tariff data is a work of the US Government (public domain).