The annual cycle
last year's position is found, re-read and re-justified, because nothing recorded whether it was still the firm's view.
the position, the authority it cited and any later advice that qualified it come back together, dated.
For tax practices
Positions, filings and rulings your practice already took
A position taken for a client three years ago, the authority it rested on, and whether the law has moved since are three different documents and one question. Nemosyne holds the position with its basis attached, so the question can be asked rather than researched.
Where the work already lives.
The practice's own record, read where it already sits.
- Advice letters and memoranda in the document store — the position, and the reasoning behind it.
- Filed returns and computations, with the disclosures that accompanied them.
- Rulings, clearances, and correspondence with the authority.
- Client structure charts and the entity records a position depends on.
- Engagement letters, which fix the scope of the advice that was actually given.
A position is only as good as what it rested on, so the authority the advice cited is kept with the position, in the advice's own words. When the law moves, you can ask which positions mention it, and each comes back with its letter.
Three kinds of recurring work.
The same three shapes come round every quarter. What changes is not that the work disappears — it is that nobody has to reassemble the record before it can start.
When the law moves
someone works out which clients are affected by asking partners, and the list is as good as their recall.
you ask which positions cite the changed authority, and each comes back with its client and its letter.
A new client, an old question
the practice's own prior answers are unreachable, so the research is repeated at cost.
the earlier advice comes back with its facts, its caveats and the authority it relied on, dated.
A worked example.
Illustrative — the firms, names and figures below are invented
Calder & Vane advised Thornbury Group in 2023 on the treatment of an intra-group financing arrangement. In 2025 the client asks whether that advice still holds.
- Advice · 2023
- Concludes the arrangement is within the safe harbour, citing the guidance as it then stood.
- Return · FY23
- Filed on that basis, with a disclosure describing the arrangement.
- Clearance · 2023
- Sought and not obtained; the file records a decision to proceed without one.
- Guidance · 2024
- The authority revises the safe harbour test.
- Engagement letter
- Scope covers the financing arrangement only; no transfer-pricing review was engaged.
The advice cites guidance that has since been revised, and the file records that no clearance was obtained. Asked whether the advice still holds, Nemosyne returns both with their documents, because the position on file reads as settled and its basis may no longer be.
What your assistant answers.
Through the same Claude, ChatGPT or Cursor your firm already uses — one connection per firm, and each person sees only what they are allowed to see.
Does our 2023 advice to Thornbury still hold?
The advice relied on the safe harbour test as it stood in 2023, and that guidance was revised in 2024.
No clearance was obtained, and the file records the decision to proceed without one.
The partner opens the 2023 letter and the 2024 guidance side by side, rather than starting the research over.
The first thing we would ask you.
Are your clients companies, individuals, or both?
It is the first thing the setup asks. Nemosyne models companies and their filings today, and individual taxpayers are not yet covered, so the answer tells us how much of your book it will hold before anything is read.
Questions this raises.
- Is this giving tax advice?
- No. It returns what your practice already advised, with the document and the authority it cited. The judgment stays with the person who signs the letter.
- How does it handle superseded authority?
- A later document does not erase an earlier one. The 2023 position stays readable with its date and the authority it cited, and revised guidance in your record can be read beside it. Whether the revision changes the answer stays with the adviser.
- Can it read a filed computation?
- Yes. A computation is read into taxable profit, charge and effective rate for the period, each citing the document. A spreadsheet is laid out as a table before a model reads the figures from it, and a scanned filing can go down a heavier parse route.
- What about confidentiality between teams?
- Visibility is stamped from the source at capture and every answer is trimmed to the person asking, so two teams on the same floor get different answers where their access differs.
Start with what your firm already knows.
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