Files
wanderbooks/docs/spec
swaits 0322778683 docs(arap): B-41, the bookspec examples, and the four registers (P4b S7)
rules.md B-41 states the write-off: the direct method the owner chose
(A-5), Dr 6990 / Cr 1200 with the receivable tagged, at most what is
owed and at most the least owed from that day on (a partial write-off as
§1.166-3(a) allows), refused on cash-basis books (§1.166-1(e)), its
evidence filed in the same call (§1.166-2(a)); bills are never written
off (ASC 405-20-40-1); and a recovery is not a new movement (D-49): the
same year, reverse the write-off and record the payment; a later year, a
plain entry to a bad-debt-recoveries revenue account, the invoice staying
written off (IRC §111).

bookspec states B-41 for the first time and gives B-38 its example: two
new examples, bad-debt-direct-write-off (two partial write-offs of one
invoice, the balances and the trial balance worked by hand) and
arap-hand-control-posting-refused (a hand line an earlier version wrote
replays, the same line written today is refused). The example schema
gains the dated write_off event, lets a refused entry say so (an entry
posts whole or not at all; older and refused never combine), and its
refusal vocabulary gains untagged_control_line, B-38's control guard.

The registers: docs/architecture.md names the new tool group;
docs/receipt-store.md lists invoice.written_off and what replay does with
it; docs/parity.md records the slice (no row changes status, the floor
stands); docs/testing.md records every test and what P12 must mutate;
docs/verification.md the two Lean theorems and what they cover.

No figure moves: no golden file changed.
2026-10-27 12:44:45 -06:00
..

Specification sources

wanderbooks' rules come from documents, not from anyone's memory. This directory holds the authorities the engine's specs cite (docs/spec/rules.md is the rule catalog), and every spec block in the code carries a SOURCE: line pointing into it.

The authority stack

There is no single "bible" of US bookkeeping. Authority is layered, and the layers differ in what they cover and in whether we may copy them:

Layer What it governs Copyright Here
Pacioli (1494), Geijsbeek translation (1914) The mechanics of double entry: debits equal credits, the trial balance, one money, writing only forward, correcting by opposite entry, closing into capital. No modern standard restates these; they predate every regulator. Public domain Vendored verbatim: sources/pacioli-1494.md
IRS: Internal Revenue Code, Treasury Regulations, publications, form instructions Records and supporting documents, retention, accounting periods and methods, information returns (1099), capitalization (de minimis, 12-month rule), partners' capital, tax basis of purchased and contributed property (sources/irs-partnership-basis.md), payroll taxes, rounding on returns, return line items for tax categories (sources/irs-tax-lines.md) Public domain (17 U.S.C. §105; IRS.gov's content policy) Vendored verbatim: sources/irs-*.md, sources/us-public-domain-status.md
File formats: Intuit (QuickBooks Online bank CSV, QuickBooks Desktop IIF), ECMA-376 Office Open XML, Microsoft Excel limits, Avery label sheets What ledger-import reads and writes: bank/card CSV layouts and signs, IIF journal entries, how XLSX stores numbers and Excel's 15-digit precision, asset-label sheet geometry (Avery 5160) © Intuit Inc.; © Ecma International; © Microsoft; © Avery Products Corporation Cited with short quotes, URLs, and hashes: sources/intuit-bank-csv.md, sources/intuit-iif.md, sources/xlsx-numbers.md, sources/avery-5160.md
FASB Accounting Standards Codification (ASC) Authoritative US GAAP: cash flows (ASC 230), revenue and principal vs agent (ASC 606), foreign currency (ASC 830), credit losses and aging (ASC 326), property and depreciation (ASC 360) © Financial Accounting Foundation Cited by paragraph with short quotes only (in rules.md; the paragraphs read, with where and when, in sources/fasb-asc.md and below)
FASB Concepts Statement No. 8, Chapter 4 (2021) Definitions of the five elements (it replaced Concepts Statement 6) © Financial Accounting Foundation; non-authoritative Cited with short quotes only
Textbooks (OpenStax Principles of Accounting, Vol. 1) Conventions no standard states: normal balances, closing-entry mechanics, straight-line depreciation arithmetic CC BY-NC-SA 4.0 (incompatible with this repo's license) Cited with short quotes and attribution only
Convention or decision Where no authority speaks: aging bucket edges, cent rounding among members, closed-period locks — Stated as CONVENTION or CHOICE, with who decided and when

How to read a SOURCE line

SOURCE: Pacioli ch. 36 (sources/pacioli-1494.md); IRS Pub. 583 (sources/irs-records.md)
SOURCE: ASC 830-20-30-1 (cited, rules.md B-3)
SOURCE: CHOICE (the owner, 2026-10-13)
SOURCE: CONVENTION (QuickBooks aging); nearest authority ASC 326-20-55-38 (illustrative)

A rule whose only source is CONVENTION or CHOICE is a candidate for a human to confirm or overturn; nothing else is.

Rules added later never lock out older books

When a rule is tightened (a check added to a command), books written before it must still open. Journal replay and the SQLite cross-check read history through the engine's replay_* commands, which skip checks added later; new commands go through the checked ones. Pinned by books_written_under_older_rules_still_open (ledger-store).

Vendoring rules

  • Public-domain texts are copied verbatim (whitespace normalized), each with its URL, retrieval date, and the SHA-256 of the retrieved file, so anyone can check the excerpt against the original.
  • Copyrighted sources are cited by paragraph, quoted briefly, never copied.
  • When an authority changes (the IRS revises a publication; a statute is amended), add the new text beside the old with its effective date. Rules that depend on dates (1099 thresholds) must say which text applies when.
  • Rules that change with the law are registered in crates/ledger-core/src/rules.rs with the years they are known for and a review date. Past what it knows, the engine refuses rather than guesses; from the review date, the MCP digest and the viewer flag the rule. Whoever updates one (human or agent) vendors the new official text here, extends the rule, and sends the change upstream: a pull request at https://github.com/swaits/wanderbooks (best), or an issue.

Open: sources we could not verify

Read on 2026-10-13 through Deloitte's free DART roadmaps, which reproduce ASC text: ASC 230-10-45-16 and -28, 326-20-55-37/38, 606-10-25-23, 45-2, 55-37/38, 830-20-30-1. Read directly in the ASC basic view on 2026-10-14 (sources/fasb-asc.md): 360-10-35-4, 340-10-05-2/4/5, 210-10-45-1/2/5, 230-10-45-7/10/12/13/14/15, 606-10-55-36 through 55-38. Read on 2026-10-20 where public sources reproduce the Codification (EY's FRD on the statement of cash flows, July 2026; FASB ASUs 2016-15 and 2016-18; Deloitte's public DART Roadmap): ASC 230-10-10-1, 45-1, 45-4, 45-5, 45-8, 45-9, 45-12(c), 45-13(c), 45-14(a), 45-15(a)/(c), 45-16(a)/(b), 45-17, 45-24 to 45-26, 45-28 to 45-31, 50-3 to 50-8, and 830-230-45-1; each checked again against the same sources in the P3 review (numbers, pages and wording hold). Open: 105-10-05-1 to 05-3, read only in their 2009 text (ASU 2009-01, and as Wiley GAAP 2020 quotes them); their current wording is unconfirmed. Also open (P3 surface review, 2026-10-21): ASC 230-10-45-15(f) (debt issue costs, cited by B-14 rule 11) is in neither list above; ASC 606-10-25-31, 25-32 and 55-20 (B-16's over-time method) are not yet read; B-15 rule 6 cites ASC 250 with no paragraph; B-17's 606-10-55-39 is in neither list. Each is to be read in the ASC basic view and listed in sources/fasb-asc.md before it is relied on further. Also open (plan P4b, 2026-10-23): B-38 cites ASC 310-10, 405-20-40-1 and 606-10-45-4, none yet read in the ASC basic view; B-38 keeps the CONVENTION label until they are vendored with a SHA-256, as P4b.16 lists with the sources B-39 to B-41 will need.