US Tariff Change Watch — connector documentation

MCP endpoint: https://us-tariff-watch.connectorbay.com/mcp
REST API: POST https://us-tariff-watch.connectorbay.com/v1/tools/{tool_name}, described by the OpenAPI 3.1 spec at https://us-tariff-watch.connectorbay.com/openapi.json
Transport: Streamable HTTP, stateless, MCP specification 2025-06-18 or later
Authentication: none required. An optional Authorization: Bearer <key> raises rate limits.
Health: https://us-tariff-watch.connectorbay.com/health · Tool schemas: https://us-tariff-watch.connectorbay.com/tools.json
Publisher: Unify Dynamics LLC · connectorbay.com/us-tariff-watch · agent@connectorbay.com

What US Tariff Change Watch is for

US Tariff Change Watch tells an importer what changed in US tariff paperwork since last week. It reads two public US government services, both keyless: the online Harmonized Tariff Schedule of the U.S. International Trade Commission (hts.usitc.gov) and the Federal Register API of the Office of the Federal Register. hts_release_changed compares the current HTS release name with the one you saw last time. watch_headings takes your HTS numbers, reads their lines (including Chapter 99 lines that name them) and diffs them against the snapshot returned by your previous run: lines added, removed or changed, with the before and after text of the general and column 2 rates. fr_tariff_documents_since lists Federal Register rules, proposed rules and notices about tariffs from USTR, CBP and BIS (or agencies you choose) and flags those whose title or abstract names one of your HTS numbers. presidential_actions_index lists presidential proclamations, executive orders and other presidential documents about trade, using Federal Register presidential documents (the USTR web page is not read: it is an HTML page with no API). weekly_tariff_brief runs all four and returns the state to pass back next week. Nothing is stored: the last-seen release and the snapshot travel with each call. It reports that something changed, not what duty an import owes: additional duties, antidumping and countervailing duties and classification are outside it. Federal Register keyword search is noisy and cannot search HTS numbers. General information, not customs or legal advice.

Ask your assistant things like:

"Has the HTS moved past 2026HTSRev19?"
"Which tariff notices did USTR, CBP and BIS publish since 22 September, and do any name HTS 8516.71.00?"
"Watch HTS 8516.71.00 and 7210.30.00 and tell me what changed since my last snapshot."
"List the presidential proclamations and executive orders about trade published since 1 September."
"Run my weekly tariff brief: last seen release 2026HTSRev19, headings 8516.71.00 and 7210.30.00, notices since 22 September."

What it does

hts_release_changed: Has the Harmonized Tariff Schedule been revised since the release you last saw? Current release name from the online HTS and whether it differs from yours.
fr_tariff_documents_since: Federal Register rules, proposed rules and notices about tariffs from USTR, CBP and BIS (or agencies you choose) since a date, with a flag on any whose title or abstract names your HTS numbers.
watch_headings: Read the schedule lines for a list of HTS numbers and diff them against the snapshot from your last run: lines added, removed or changed, with before and after rate text.
presidential_actions_index: Presidential proclamations, executive orders and other presidential documents about trade, tariffs and imports, by title and date, from Federal Register presidential documents (the USTR page is not read).
weekly_tariff_brief: One weekly digest: HTS release change, heading diffs, new tariff notices and presidential trade actions, plus the state to pass back next week.

Data sources

Reference data from official sources (federalregister.gov, hts.usitc.gov); every answer states its source, date and validity period.

What it is not

US Tariff Change Watch is independent; not affiliated with, endorsed by or operated by any government body, central bank, standards body or scheme operator. Names of rails, schemes and standards are used only to say what a tool works with. It is read-only: it never sends, pays, files or signs anything for you, and it never looks up private individuals.

Not advice. General information only, not customs, legal or tax advice. US Tariff Change Watch is an independent tool: it is not affiliated with, endorsed by or operated by the U.S. International Trade Commission, U.S. Customs and Border Protection, the Office of the U.S. Trade Representative, the Office of the Federal Register or any other government body. A changed schedule line or a Federal Register notice is reported as published; it does not say what duty applies to an import. Tariff classification and the duties owed are decided by CBP, and duty programs change often. Check the cited official source and confirm with a licensed customs broker or qualified professional before you rely on a result.

Built for: United States. Languages: English.

Tools

Schedule changes (HTS)

hts_release_changed — Current Harmonized Tariff Schedule release name from the online HTS, and whether it differs from the release you last saw. Says a new revision exists, not which lines changed (use watch_headings for that). Use for "Has the HTS moved past 2026HTSRev19?" or "Which HTS revision is current?". Args: last_seen.

watch_headings — Read the schedule lines the online HTS returns for your HTS numbers (their own lines and Chapter 99 lines that name them) and diff them against the snapshot from your last run: lines added, removed or changed, with before and after general and column 2 rate text. Reports that something changed, not what duty applies. Use for "What changed for HTS 8516.71.00 and 7210.30.00 since last week?" or "Did a new Chapter 99 line appear for my HTS number?". Args: headings, previous.

Notices and actions

fr_tariff_documents_since — Federal Register rules, proposed rules and notices about tariffs from USTR, CBP and BIS (or agencies you choose) since a date, newest first, with a flag on any whose title or abstract names one of your HTS numbers. Keyword search is noisy and cannot look up HTS numbers. Use for "Which tariff notices did USTR, CBP and BIS publish since 22 September?" or "Does any new notice name HTS 8516.71.00?". Args: since, until, terms, agencies, types, headings, limit.

presidential_actions_index — Presidential proclamations, executive orders and other presidential documents whose titles mention trade words (tariff, duties, imports, trade, customs and similar), newest first, with signing and publication dates. Built from Federal Register presidential documents, not from the USTR web page. Use for "Which presidential trade actions were published since 1 September?" or "Any new proclamation on tariffs this month?". Args: since, until, match, limit.

Weekly brief

weekly_tariff_brief — One weekly tariff digest: did the HTS release change, what changed on your watched HTS numbers since the last snapshot, which new Federal Register tariff notices came out (flagged when they name your numbers) and which presidential trade documents were published. Returns next_state to pass back next week. Nothing is stored. Use for "Give me this week's tariff brief for HTS 8516.71.00 and 7210.30.00." or "Run my weekly tariff check.". Args: last_seen_release, headings, previous, since, until, terms, agencies, limit.

Conventions

Read-only. Every tool reads public data or computes; nothing is written anywhere and nothing about the user is stored.
Result envelope. ok: true with data, or ok: false with a structured error (bad_input, not_found, upstream_error). degraded lists optional sources that were unreachable.
Rate limits. Free tier 60 tool calls/minute and 300/day per user (keyed on the user identifier supplied by the host agent, else client IP); Pro keys raise this. Over-limit calls return HTTP 429 with Retry-After. initialize and tools/list are never counted.

Support

agent@connectorbay.com · connectorbay.com/us-tariff-watch/support