Tariff Monitor: US Import Duty & HTS Lookup

tariffmonitor-mcp

tariffmonitor-mcp is US import tariff lookup software by 0xpi for AI agents and developers: an MCP server that looks up 19,856 HTS codes and estimates stacked US import duty rates (MFN, Section 301 and Section 232) by country of origin. Free and open source, with a free hosted endpoint. It is not an electricity or energy tariff tool. Made by 0xpi; 0xpi is not affiliated with Pi Network, any cryptocurrency or blockchain project.

MCP server for the Tariff Exposure Monitor — a live US import tariff calculator covering 19,856 HTS codes.

Give Claude (or any MCP-compatible AI) the ability to look up real stacked tariff rates and see what changes when the Section 301 China product exclusions end (through 11:59 p.m. EDT on November 9, 2026 per the Federal Register, FR Doc. 2025-21671; USTR's 26 Nov 2025 press release says "until November 10, 2026") for any product.

What it does

Three tools:

Effective-date-aware (1.5.0, 4 Nov 2026). Pass date to calculate_tariff or compare_origins and the rule in force on that entry date is applied (default: today, US Eastern). For products of China the server applies the 178 Section 301 product exclusions by statistical number (HTSUS ch. 99 U.S. note 20(vvv) and 20(www), headings 9903.88.69/.70, through 9 Nov 2026 per FR Doc. 2025-21671): a whole-number exclusion takes the List duty off the total, a description-limited one is reported with the rate for matching goods. It also applies the maritime Section 301 headings: 9903.92.10 (+25% on ship-to-shore gantry cranes since 27 Sep 2024) and, from 10 Nov 2026, 9903.91.14 (+100% on those cranes, on top of 9903.92.10 as U.S. note 31(l)(i) states) and 9903.91.12 (+100% on intermodal chassis, shown as "up to" because chapter 99 does not say how it combines with List 3). Each answer cites its chapter 99 note and Federal Register document, and says when it depends on a proposed, not final, extension (FR Doc. 2026-21755 proposes suspending the maritime duties to 9 Jan 2027). A daily Federal Register check moves these dates the day a final notice is published.

Example exchange: a real capture from the live hosted endpoint (/mcp-free) on 2026-10-26 (version 1.4), not a mock-up:

You: What's the tariff on athletic footwear from China, and what does it cost me at $800k/year?

Claude: [calls lookup_hts_code query="athletic footwear", then calculate_tariff hts_code="6404110000", origin_country="CN", annual_import_value_usd=800000]

Note: 6404110000 is not in the schedule. This rate is for heading 640411, resolved to 6404112030.

HTS 6404112030 — For men Origin: CN Data checked: 2026-10-24

Rate stack: MFN base rate (10.5%): +10.50% Section 301 China, List 4A (heading 9903.88.15): +7.50% Section 301 forced-labor tariff (2026): +12.50% Total current rate: 30.50%

No rate change projected for this code/country combination when the Section 301 China exclusions end.

Section 301 forced-labor tariff (FR Doc. 2026-15181; data checked 2026-10-24): included (+12.5%). China: +12.5%, heading 9903.05.31. Stacks on other Section 301 duties.

Section 232 steel, aluminum and copper coverage is checked by HTS line (U.S. note 16(c)); the other Section 232 programs (vehicles and parts, wood products, trucks, semiconductors) are flagged when the line is named in their notes. Goods subject to any of them are exempt from this layer (U.S. note 52(f)).

Section 301 China product exclusion end, two official wordings: the Federal Register notice (FR Doc. 2025-21671, 90 FR 55232, 1 Dec 2025) extends the exclusions "through 11:59 p.m. eastern daylight time on November 9, 2026"; the USTR press release of 26 Nov 2025 says the 178 exclusions "have been extended until November 10, 2026". The Federal Register text is the legal one. This calculator does not model individual exclusions.

Dollar impact at $800,000/yr import value: Current annual duties: $244,000

The Section 301 forced-labor layer (USTR, 60 economies, entries from 12:01 a.m. ET on 24 Jul 2026, Federal Register 91 FR 47318, HTS 9903.05.20-9903.05.84) is 12.5% or 10% depending on origin; for the EU and Taiwan it tops the MFN rate up to 10%, and for Japan, South Korea and Switzerland up to 12.5%. Products listed in U.S. note 52 and goods carrying a Section 232 layer are exempt; exemptions that depend on facts the tool cannot see (USMCA or CAFTA-DR qualification, civil-aircraft or pharmaceutical use) are stated as assumptions in the answer.

Rates change, and a rate is per HTS code and origin country - treat the numbers above as the shape of the answer, not as a quote for your shipment. The tool never invents a rate: if the upstream is unreachable or the code is not in the schedule, it says so instead of estimating.

Try it without installing (free hosted remote)

A keyless public endpoint serves the same three tools over Streamable HTTP:

https://adcreator-ai.com/mcp-free

• No key, no signup. Limits: 25 tool calls per IP per day, and 500 per day across all users (reset 00:00 UTC). initialize and tools/list do not count.
• Over the limit you get a JSON-RPC error (HTTP 429) that points to the npm package below, which has no limit because it runs on your machine.
• Each call is logged (time, method, tool, status, user agent, client IP, and the client name the MCP client reports) to measure use and filter scanners. The log does not store tool arguments. Log lines are deleted after 365 days. Full details: Privacy Policy.

Claude Code: claude mcp add --transport http tariffmonitor https://adcreator-ai.com/mcp-free

Install (Claude Desktop)

Add to your claude_desktop_config.json:

{

"mcpServers": { "tariffmonitor": { "command": "npx", "args": ["-y", "tariffmonitor-mcp"] } } }

Restart Claude Desktop. The lookup_hts_code, calculate_tariff and compare_origins tools appear automatically.

Install (Cursor / other MCP clients)

{

"mcp": { "servers": { "tariffmonitor": { "command": "npx", "args": ["-y", "tariffmonitor-mcp"] } } } }

No API key required

The tool calls the free public API at adcreator-ai.com. No signup, no rate limits for reasonable use.

Related

• Free tariff calculator — browser version
• Official US Harmonized Tariff Schedule — the authoritative rates

Built by Dale Weaver / 0xpi.

Privacy Policy

The hosted endpoint https://adcreator-ai.com/mcp-free is covered by the privacy notice at https://adcreator-ai.com/public/mcp-privacy.html. In short:

• Collected: for each request, the time, MCP method, tool name, status, duration, client IP address, user agent and the client name/version sent at initialize. Tool arguments are not stored in the call log. Rate limits use a hashed form of the IP address.
• Use: answering the call, rate limits, abuse and scanner filtering, and counting use. No profiling, advertising or sale of data.
• Sharing: none beyond hosting providers. HTS lookups go to our own tariff database (adcreator-ai.com), which records the HTS code and origin country of each rate lookup without your IP address. No data is sent to AI providers.
• Retention: call-log lines are deleted automatically after 365 days; rate-limit counters last one day.
• Contact: customer.service@0xpi.com for access or deletion requests.

The npm package (npx -y tariffmonitor-mcp) runs on your machine and sends only its lookups (product search words, HTS codes and origin countries) to the same tariff database.