Two experts inside Claude and ChatGPT: U.S. customs and federal tax. Method first, the guidance and the text at the vintage that governs, the source on every answer. Not a search engine — reasoning that holds its conclusion.
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A subscription per connector — and inside it, far more than documentation: the working method of the trade and the technical know-how that applies it, built into the connector. A free trial to start; every answer carries its citations, to the line and the section.
U.S. customs at the entry date: the schedule, the dated measures, valuation, origin, the case.
And it produces: entry drafts posed on the documents, computed bills, protests and disclosures drafted — the case worked end to end.
8517.62.00
19 U.S.C. § 1592
The right section, at the right tax year: the IRC vintaged, guidance life-chained, precedent weighed.
And it produces: the file analyzed in full, positions computed and sourced, returns drafted line by line, procedural drafts to practice standards.
26 U.S.C. § 174A
Rev. Proc. 2013-13
Like the railroad: one line laid straight to the objective — the connector carries the trade’s method and its procedures, not a search box — and the order of dates is real.
One click from claude.ai or Claude Desktop: the connector arrives prefilled, name and address included. In ChatGPT: same address, under Settings → Connectors, once Developer mode is on (Settings → Apps → Advanced settings).
Search, section reading in its dated vintage, sourced computation: the answer is built on the texts, not on recollection.
Every claim carries its exact citations: section, vintage, court, date. The decision stays with the professional.
The connectors run in Claude and ChatGPT; answers gain depth with a capable model — Claude Opus 5, or GPT-5.6 Sol (or newer).
The same question, two answers: one resting on a model’s recollection, the other going back to the text. “Has Rev. Proc. 2013-13 (home office safe harbor) been modified or superseded?”
A model recalling
“It rings familiar as the simplified method, and nothing suggests it changed. It is probably still fine to rely on.” No citation is offered, and the recollection is dated nowhere.
Unverifiable
A model reading
“The life chain is pulled and read: every modifying or superseding action, tagged and dated, down to the text in force today.” The answer arrives carrying its citations.
A practitioner’s question, the answer in brief, and the citations that let you verify.
“Aluminum extrusions entered in March 2024, and the AD order has changed since: is the bill computed at the entry-date rates, or today’s — and what exactly changed in between?”
The stack is read at the entry date — each layer carrying its dated Federal Register citation — and every change since is flagged, dated and cited, so the two states of the order can be compared line by line.
Citations HTSUS ch. 99 Federal Register, dated AD/CVD order
“Section 1202 QSBS for stock issued in 2021: which vintage applies — the statute as it read then, or as it reads today?”
Stock issued in 2021 is read under the statute of its year: the 2021 vintage of § 1202, not today’s text — and the differences with the current vintage are flagged.
Citations 26 U.S.C. § 1202 as of 2021 IRB chain
Two fronts, five trades: what professionals hand to the record, and the question they ask first.
Licensed customs brokers. You hand it classification calls and entry files, argued from the schedule, its notes and the rulings. “We’ve filed 8517.62.00 for three years; a competitor’s ruling reads the same device elsewhere: change, protest, or disclose?”
Trade compliance officers. You hand it screening, forced-labor exposure and the dated tariff stack, before the goods move. “Detained under UFLPA at Long Beach: which rebuttal evidence has actually moved these cases?”
Import and export managers. You hand it the import file and the export controls that follow it. “Entered in March 2024, the AD order changed since: which rates compute the bill?”
Tax attorneys. You hand it the point-in-time statute, life-chained guidance and weighed precedent, from planning through controversy. “§ 1202 stock issued in 2021: which vintage applies?”
CPAs and enrolled agents. You hand it season materials read cell by cell, and returns drafted line by line for review. “MFJ, both spouses over 65: the 2024 standard deduction, and which Rev. Proc. sets it?”
For the full framework: frequently asked questions and legal notice.
From the official corpora carried in the legend: the HTSUS and the dated chapter-99 chronology, Title 19 and 19 CFR, the IRC and 26 CFR, IRB guidance, CROSS rulings, treaties and the courts. Every answer points to the exact citation, for verification at the source.
Hamilton is a subscription service (a professional plan), with a free trial to start. During the launch period the connector is open, so the trial needs no card. Pricing will be announced here before billing begins, and adding will stay just as simple.
No: a sourced research aid. The professional verifies the citation given, weighs the situation and decides.
Pick your desk: the connector opens prefilled in Claude — or adds to ChatGPT, same address.
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