Mark Eaton
0238f5e5d7
Real-draft testing on the HML bibliography surfaced inconsistent preposition capitalization in headline-style titles: the formatter was sometimes lowercasing "among", "beyond", "within", "into", etc. and sometimes capitalizing them, violating CMOS 8.159. The behavior was nondeterministic across similar entries — smoking-gun evidence of GPT-5 judgment drift on a rule the existing prompt only implicitly covered via rule 6's "headline-style capitalization". Rule 29 makes the carve-out explicit and instructs the model to apply CMOS 8.159 independently of the source's casing, with: - a substantial but illustrative preposition list including "as" (which CMOS 8.159 calls out as always lowercased) - an explicit scope restriction to PREPOSITIONS, with subordinating conjunctions (If, That, Because, Although, Unless, etc.) capitalized - a CMOS 8.161 carve-out for hyphenated compounds: the first element is always capitalized (so "In-School" stays, not "in-School") - a first/last-word exception covering "last word of the main title immediately before a subtitle colon", which the model was treating as mid-title Verified on the 134-entry HML draft: ~17 entries now produce more CMOS-correct forms, and two consecutive re-runs show no new rule- 29-related regressions. Observed GPT-5 drift on orthogonal axes (multi-author inversion, inner-quote style, periodical italicization) washed out across re-runs, consistent with the ~5% single-run variance documented in project memory. Rule count: 28 -> 29. No linter version bump required.
cmos — Chicago Manual of Style 18 bibliography reformatter
A Python tool that reformats the bibliography section of an English-language markdown draft to CMOS 18th edition, notes-and-bibliography form.
Accuracy-first, iterative, built with a karpathy/autoresearch-style dev loop.
See program.md for the goal specification and
/home/claudecode1/.claude/plans/pure-mixing-yao.md for the implementation plan.
Quick start
uv sync
uv run pytest
uv run cmos format path/to/draft.md > out.md
Layout
src/cmos/formatter.py— the iterable artifact (edited every loop iteration).src/cmos/parser.py— extracts the bibliography section from a draft.src/cmos/linter.py— deterministic CMOS 18 rule checks (versioned).src/cmos/cli.py—cmos formatentry point.harness/score.py,harness/diff.py— frozen scoring.exemplars/— TOML test corpus.tests/— pytest suite (linter, parser, formatter, cli).rough_drafts/— user-supplied messy drafts for ad-hoc iteration.logs/— per-run scores, model ids, linter version hashes.