New vendored sources (docs/spec/sources/): Intuit's bank CSV upload and
IIF formats, ECMA-376 / Excel number storage, and the IRS form lines the
tax categories map to.
IIF export (rewritten to Intuit's IIF Import Kit):
- declares every account first (!ACCNT NAME, ACCNTTYPE, ACCNUM): an
undeclared account is created in QuickBooks "as a new bank account";
the MCP export types them (cash accounts BANK, the control accounts AR
and AP, registered fixed assets FIXASSET, the rest by type);
- subaccounts by colon path, parents first; colons in a name replaced;
- ASCII only (IIF is ASCII text), dashes and quotes transliterated;
- the kit's 2007+ journal layout and M/D/YYYY dates; an entry using an
undeclared account is refused.
Bank CSV:
- the 4-column layout is money out then money in by position, which
matches Intuit's "Credit, Debit" and banks' "Debit, Credit" both (the
doc's "Expense, Income" labels were wrong, the parsing was not);
- a slash date's order comes from the file (a part over 12 settles it)
or the caller's new date_order, never a guess: Intuit recommends
dd/mm/yyyy, US banks write mm/dd/yyyy;
- fractions of a cent and double negatives ("(-5)") are refused; the
header is recognized on the first non-blank row.
Chart CSV: a blank code or name is refused with its row (found by the
new fuzz_import_csv target), and the core now refuses a blank account
code or name too (replay keeps older books).
MCP:
- books.import_chart_csv and books.import_bank_csv rehearse the whole
file on a copy of the ledger first: a bad row anywhere refuses the
file (before, a duplicate within the file, a parent after its child,
or a date in a closed period left earlier rows behind);
- bank rules: the longest matching pattern wins (they arrive in a map,
so "first match" changed from run to run).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
Three spec decisions from Stephen (2026-10-13), each test-first:
- A child account has its parent's type (ParentTypeMismatch): a child
subdivides its parent. Test: a_child_account_has_its_parents_type.
- Periods nest (a month in a quarter in a year) but never partially
overlap (PeriodsOverlap; a refusal uses no id). Test:
periods_nest_but_never_partially_overlap.
- A line's account must exist and take postings when the line is added,
not only at post (UnknownAccount / PlaceholderAccount from add_line
and add_line_fx); posting still re-checks. Two older tests that pinned
the post-time refusal now check both (the post-time check is reached
through the unchecked replay path, as old journals can).
Compatibility: replay reads history through new Ledger::replay_*
commands (add_account, add_line, add_line_fx, create_period) that skip
checks added later, so books written before these rules still open.
The contract test books_written_under_older_rules_still_open writes such
a journal directly and found, on its first run, that the SQLite
cross-check rebuild used the checked commands and would have failed
verification ("sqlite projection can't be read back"); it now replays
too. Documented in docs/spec/README.md; decisions recorded in rules.md
(B-1, B-4, B-12).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
Stephen (2026-10-13): when what wanderbooks knows is stale, check the
date, research it or ask the owner or CPA, and update the rule for
everyone with a pull request (best) or an issue (worst).
- ledger_core::rules: a registry of rules set by law that change over
time. Each says the years it's known for, its rules.md entry, its
vendored official source, and a review date. stale_rules(today) is
pure; the engine has no clock.
- The 1099 threshold is the first: $600 through 2025, $2,000 in 2026,
then indexed for inflation (26 U.S.C. §6041(h)). default_threshold
and vendor_1099_report now return Result; for 2027+ they refuse with
LedgerError::RuleNotKnown, whose message says what to do: get the
figure from the official source or the owner/CPA, pass it explicitly,
then open a PR (or issue) at github.com/swaits/wanderbooks. Before,
2027+ silently used $2,000.
- MCP: books.vendor_1099 relays that refusal; books.digest gains
stale_rules; the server instructions tell the agent the procedure (and
how to handle control-account conflicts: explain, never renumber).
The CPA package writes a NOT-INCLUDED note instead of a guessed 1099
worksheet.
- Viewer: "Needs attention" shows each stale rule with a ready prompt
for the agent; the 1099 page explains instead of guessing.
Review date for the 1099 rule: 2026-11-01, when the IRS usually
publishes next year's inflation adjustments (CONVENTION, marked as such
in the registry).
Tests: an_unknown_year_threshold_is_never_guessed,
dated_rules_go_stale_on_their_review_date (dates passed in, so no clock
in the test), MCP stdio: 2027 refused with guidance, explicit threshold
accepted, digest carries stale_rules (asserted date-independently).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
Stephen asked that specs come from recognized documents, not from
anyone's memory. There is no single US bookkeeping bible; authority is
layered, and this records it:
- docs/spec/sources/: verbatim excerpts (whitespace normalized), each
with URL, retrieval date, and the SHA-256 of the fetched file, of
public-domain texts: Pacioli's 1494 treatise in Geijsbeek's 1914
translation (double entry, the trial balance, one money, write only
forward, correct by opposite entry, close into capital); IRS Pub. 583,
538, 946, 15; the 1099-MISC/NEC instructions (2025 and 2026); 26 U.S.C.
§6041, §6041A, §704; Treas. Reg. §1.263(a)-1(f) and -4(f); Notice
2015-82; Rev. Proc. 98-25; Form 1065 instructions; 17 U.S.C. §105. The
excerpts were extracted by matching each passage against the fetched
file, so none can contain text the source doesn't.
- docs/spec/rules.md: the rule catalog, B-1 to B-22. Each rule says
AUTHORITY, CONVENTION, or DECISION; cites its sources (FASB's
Codification and Concepts Statement 8 and OpenStax quoted briefly,
never copied: copyright and CC BY-NC-SA); and names the code that
enforces it and the tests and proofs that check it.
- Spec blocks in the code now carry SOURCE: lines into the catalog;
AGENTS.md makes sourcing rule 0 of the formal-methods bar.
Corrections the sources turned up: the de minimis limit is $500 in the
regulation and $2,500 by Notice 2015-82 (both now cited); 1099
thresholds after 2026 are inflation-indexed, so the engine's flat
$2,000 for 2027+ is an open question (B-19). Unverified ASC paragraphs
(360-10-35-4, 340-10, 230-10-45-10, 606-10-55-37B, 210) are listed in
docs/spec/README.md until someone with a FASB basic-view login reads
them.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
swaitsandClaude Opus 5.5