Hamilton Tax & Law · Professional plan
The Code, read as of the tax year.
Federal tax research for Claude and ChatGPT: the IRC one vintage per tax year, 26 CFR, IRB guidance read to the end of its life chain, treaties with 69 countries article by article, the Tax Court with its barometer. It analyzes, computes to the day, drafts the return and works the controversy — inside Claude and ChatGPT, reasoned from the governing vintage, never merely searched.
Who Hamilton Tax & Law is for
For practitioners whose position has to hold to the exact tax year, from the return to the controversy. Each asks their own question, and the answer comes back sourced.
Advising and filing
Tax attorneys. The statute point-in-time, guidance read to the end of its chain, and treaty text with the saving clause checked on the page. Founder stock from 2019, a co-founder redeemed in 2020 — does it poison § 1202 for later sellers?
CPAs and enrolled agents. Season materials parsed cell by cell, and returns drafted line by line, ready for your review and your signature. S corp shareholder died mid-year — how is the year split, and does a § 1377(a)(2) election help?
Controversy and cross-border
Controversy teams. Procedure from the first notice to the statutory notice of deficiency, forum posture, and a barometer read before you argue. A levy lands while an offer in compromise is pending — does § 6330 stop the clock?
International practices. Treaties with sixty-nine countries, read article by article, LOB and saving clause included, FBAR under Title 31. Green-card executive with vital interests in France — which treaty article breaks the tie?
What the shelf holds
IRC, 26 CFR, IRB guidance, precedent — the raw material the method works: the shelf is read section by section and year by year, in the version in force as of the tax year.
- The Code, vintaged by tax year The Internal Revenue Code in USLM from the Office of the Law Revision Counsel — 2,160 sections, at the current release plus one vintage per tax year back to 2017 pre-TCJA: the law of a tax matter is the law of its tax year. Title 31 for FBAR.
- Guidance, life-chained 10,838 Rev. Rul., Rev. Proc. and Notices from the Internal Revenue Bulletin, each carrying its chain — obsoleted, superseded, modified, tagged and dated — so a superseded text is never cited as current. The Internal Revenue Manual (87,559 sections) for what the agency binds itself to, PLR and TAM, and the AFRs served monthly.
- Treaties, article by article Income tax treaties with sixty-nine countries — 3,426 articles read one by one, the saving clause and LOB checked on the treaty text itself.
- Regulations and season materials Treasury Regulations — 6,146 sections of 26 CFR, all parts — 49 IRS publications served by section, the official form PDFs with their season instructions, and the printed Tax Table, EIC table and standard deduction, parsed cell by cell.
- The courts, weighed 17,531 Tax Court opinions and the appellate landmarks, a decision barometer read by side, 540 Supreme Court tax cases, and USSG Part 2T. Behind the law, the commentary shelf — JCT Bluebooks, CRS and GAO studies, Seligman's classics — each served with its scope stated: persuasive, never binding.
- Return preparation, federal only An interview first, then a Form 1040 with schedules line by line, anchored to season materials and filled on the official PDF — shipped as a draft for Circular 230 practitioner review. Federal only: SALT is out of scope, and the connector says so.
From the return to the courtroom
Not a menu of modules: the matter is followed from planning through controversy, anchored to the text in force at its date.
Positions
Income, deductions and credits, property and basis; entities from formation to exit, retirement, estate and gift; exempt organizations read against their conditions; cross-border matters read with the treaty text itself.
Compliance
Information reporting obligations form by form, penalties and interest computed to the day — every figure under the vintage in force for its year.
Controversy
Exam and appeals argued on the record, collection from notice to resolution, the choice of forum weighed with precedent — and criminal tax where it escalates.
At the desk
The record read as filed, with memos, protests and petitions drafted for signature — every position anchored to its date and citation.
Deliverables, not links
Answering is the floor. The connector works the file and hands back pieces ready for professional review.
The return, drafted
Season forms prepared line by line from the file, every figure under the vintage in force for its year — ready for practitioner review.
The computation, to the day
Penalties, interest and credits computed with the governing text attached, and treaty positions checked on the treaty itself.
The controversy, worked end to end
Response clocks and procedure checked at each step, with memos, protests and Tax Court petition drafts written to the record — from exam to petition.
The memo, anchored to its date
Substantial-authority positions written with their citations, read against the vintage in force when it mattered.
Every piece leaves as a draft with its citations — the signature stays with the professional.
Questions the way they land on the desk
Six working-day situations, to type as they come once the connector is added: the answer comes back with its citations — Code section, guidance in force, treaty article, decision.
A CPA, at year-end
S corp shareholder died mid-year: how is the year split, does a § 1377(a)(2) election help, and what basis lands in the estate?
Counsel, on QSBS
Founder stock issued in 2019; the company redeemed a co-founder in 2020. Does the redemption poison § 1202 for later sellers, and what do the regulations actually require?
A controller, on R&E
We amortized domestic research costs for 2022–2024; § 174A restores expensing for 2025. What happens to the unamortized balance — catch-up, election, or ride it out?
An attorney, cross-border
Green-card executive whose center of vital interests is in France: which treaty article breaks the tie, and what does it do to the foreign tax credit ordering?
An enrolled agent, on penalties
Exam proposes § 6662 accuracy penalties; we had substantial authority when the return was filed. Which vintage of the guidance counts — the filing date’s, or today’s?
Counsel, in collection
A levy notice arrives while an offer in compromise is pending: does § 6330 stop the clock, and which Tax Court decisions control?
Add Hamilton Tax & Law to Claude or ChatGPT
Three moves, about two minutes: the connector opens prefilled in Claude — or pastes into ChatGPT, same address.
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Click “Add to Claude”
The button opens claude.ai with the connector prefilled: the name, Hamilton Tax & Law, and the connector URL are already in place.
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Confirm the connector in Claude
On claude.ai or in Claude Desktop, approve the connector Claude shows; it joins your list. Your free trial starts right there — no card during launch.
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Ask your first question
Take one of the sample questions: the answer cites Code section, guidance in force, treaty article and decision.
Prefer to do it by hand? Paste the connector URL into Claude (Settings → Connectors → “Add custom connector”) or into ChatGPT (Developer mode on once via Settings → Apps → Advanced settings, then Settings → Connectors → “Create”):
https://hamilton-tax.147-93-52-143.nip.io/mcp
Hamilton Tax & Law runs inside Claude — claude.ai or Claude Desktop — and the same way inside ChatGPT. Answers do their best work with a capable model such as Claude Opus 5 — or GPT-5.6 Sol in ChatGPT (or newer).
Four questions, before you install
Do I need an account or a subscription?
Hamilton is a subscription service (a professional plan), with a free trial to start. During the launch window the connector is open, so the trial needs no card. Pricing will be announced on this site before billing begins, and adding a connector will stay this simple.
Is this tax advice?
No. Hamilton Tax & Law is a research aid for professionals. Return drafts and memos ship as working papers for Circular 230 practitioner review; the judgment and the signature stay yours.
Which years does the statute cover?
The current release, plus one vintage per tax year back to 2017 pre-TCJA. A 2021 matter is read under the 2021 text: the law of a tax matter is the law of its tax year.
Does it prepare state returns?
No. Return preparation is federal only: Form 1040 and its schedules, anchored to season materials. SALT is out of scope, and the connector says so rather than improvising.
The Code is open
The connector opens prefilled in Claude; the first answer comes back with its citations. In ChatGPT: same address, under Settings → Connectors, once Developer mode is on (Settings → Apps → Advanced settings).
Subscription · a free trial to start, no card.