refuse hand entries (P4b S1, part A) Plan P4b (D-45), slice S1, the engine half: rules.md B-38. - ledger-core: every receivables or payables line carries its document (Ledger.line_docs: DocRef, Movement, DocTag), written by the document commands in the step that posts it, derived on replay from the existing document events (the role's account as it stood then; payments by the ordinal rule), copied onto a reversal's mirror. Ledger::stands_on; doc_state / invoice_state / bill_state (total, paid, outstanding, status Open/Partial/Paid/WrittenOff/Void, overdue days) as of any day; ar_aging / ap_aging read them, so reversed payments and voids are right. The control guard (add_line, add_line_fx, post_entry, register_recurring) refuses untagged lines on receivables/payables, exempting a reversal's mirror of a legacy line; replay never refuses. Bounds (kernel::running_bounds, bounds_kept) on payments and reversals; a document reversal never dated before its entry; deposit/payer accounts must be cash-like and hold no role. New API: receive_payment_with / pay_bill_with (PaymentDetails: instrument, reference), void_document / check_void_document, control_check, payments_recorded, standing_payments, replay_reverse_entry. Invoice.amount_paid/status remain only as derived caches for the MCP layer until part B. cashflow bill_splits reads payments from the tags. - ledger-store: journal feature document_standing (D-39 gated) for a payment accepted only because an earlier one was reversed; receive_payment_with / pay_bill_with (instrument journaled as entry.instrument_set, reference in the description), void_document; replay uses replay_reverse_entry; schema 15 drops the projection's amount_paid/status. Fixture p4-arap-before + golden figures written by the version before S1, adjudicated in arap_standing.rs. - ledger-gui: party card, cash "coming up" and company owed totals read doc_state as of today (late from the derived state). - Lean Documents.lean (control_agrees and friends); Kani bounds_check_matches_definition, bounds_kept_is_the_definition_on_books_in_bounds; rules B-38, B-18/B-23 amended; bookspec `older = true` for legacy hand lines; tests that hand-post to 1200/2000 post as replay or renumbered. Review fixes (both reviews of part A): - control_role_of guards only an account the role is assigned to or one holding its documents' lines (a chart's own 1200 Equipment or card at 2000 is free until a document posts there); payment accounts check other roles by holds_role (type-checked). The MCP tests that failed on the guard (oracle_mcp, spec_projects) pass unchanged. - standing_payments leaves out reversals (sorted, deduped); replayed tags match the movement's side; payments_recorded counts every payment event (tagged or not, Ledger.payment_events) and refuses overflow. - The record caches settled (paid + discounted + written off) and owed (Invoice/Bill.owed, never serialized): a void never reads as paid. - assign_role: receivables/payables refuse moving onto an account with untagged lines (RoleAccountHasHandLines) and, on their control account holding a balance, say DocumentRoleHoldsBalance (no hand entry named); B-23 reworded. The reversal-mirror exemption only takes a hand line off (even chain depth); putting it back is refused. - DocStatus Overpaid and Unattached; aging leaves out credit balances; ControlCheck.attention lists out-of-bounds and unattached documents. - stands_on counts a chain in order; indexes (doc_index, doc_accounts, order_pos, reversed_by) keep the derived figures linear. - Viewer reads a post-dated document as of its own date; one state per row. bounds_kept's side-crossing documented as intended. - Tests: ten new spec_documents scenarios, stronger proptests, store proptest arap_props (live = replay = snapshot at every date, closed months), fuzz ops void/payments with details, a GUI post-dated test; Lean Step.assign / Step.release with unattached_zero kept; model limits stated in docs/testing.md and B-38. Review fixes (CPA and engineering lenses): only an assigned role's account or one holding document lines is a control account (a chart's own 1200 asset stays free); a role can't move onto untagged lines or off document lines (Lean Step.assign); a void's cache never reads as paid; no Decimal sum panics; per-document indexes keep figures linear; a replayed tag matches its side; the feature gate counts payment events; a payment's reversal is never listed as standing; an overpaid document has its own status; the viewer keeps post-dated documents. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj
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 DECISION, 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: DECISION (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 DECISION 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.rswith 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.