An engine-free reference model with exact decimals replays an example's
entries, reversals, close, bills and invoices and computes its
trial_balance, balances, profit_and_loss and entry figures from the
rules' symbolic forms (signed sums, normal sides, A = L + E + (R - X),
net income), and checks that each refusal an example expects is justified
by its rule (debits differ from credits, an amount is not positive, finer
than the minor unit, an entry already reversed, a date inside a closed
period). An example whose figure disagrees fails the specification's
build before any engine is consulted; what the model cannot derive is
reported as skipped, never as passed.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp
