This is why `decisions lifecycle` went red, and it was NOT the known flake. I
came close to dismissing it as one for the second time this session, because an
earlier red on another branch genuinely was.
The dual-format parser imported PyYAML to read frontmatter. `decisions-guard`
does `setup-python` and installs NOTHING, so once the corpus was migrated every
record became unparseable there: ModuleNotFoundError, job fails. The same would
hit the Husky pre-commit hook and every contributor's machine.
Installing PyYAML in CI is the wrong fix: READING happens everywhere -- CI, the
hook, every dev -- while WRITING happens once, in a migration a human runs
deliberately. So the read path is now dependency-free and only
`migrate_decisions_split` (the writer) still imports yaml.
A hand-rolled parser is only safe if it provably matches the library that WROTE
the files, so `test_frontmatter_reader_matches_pyyaml_on_every_real_record`
compares the two field-by-field across all 169 real records (importorskip, so it
is skipped rather than failing where PyYAML is absent) with a >100-file guard
against near-vacuity. It is narrow by construction: the frontmatter is
machine-generated with default_flow_style=False and width=10**9, so every value
is a single-line scalar, and the reader bails to None on anything nested.
Verified by running all four affected entry points against a shim that makes
`import yaml` raise: validate --base/--head, catalog --check, the kickoff guard,
and the plain validate the pre-commit hook calls. All exit 0.
refs #610
1. `date.fromisoformat` is not a YYYY-MM-DD validator. On Python >= 3.11 it also
accepts ISO basic format ("20270101") and week dates ("2027-W01-1"), so a
malformed-looking value passed the blocking check — and which forms parse
depends on the interpreter, meaning the same corpus could validate differently
on a dev machine and on the runner (pr-checks.yml pins only python-version
'3.x'). Knock-on: the catalog's Review-due section sorts on the raw STRING, so
an accepted "20270101" sorted AFTER "2027-01-15" ('-' < '0'), contradicting the
section's own "sorted soonest-first" text. Gate on ^\d{4}-\d{2}-\d{2}$ first,
which fixes both — a fixed-width zero-padded form makes string sort == date sort.
2. A present-but-empty `stale-after:` was collapsed to None by `or None` in the
parser and then skipped by a truthiness guard in the validator, so it passed as
"absent" — a field that silently never fires, which is the exact failure mode
the blocking check exists to prevent. Keep "" distinct from None and test with
`is not None`.
3. `test_catalog_is_date_independent` was partly vacuous: with no date in either
render, both sides were trivially equal after the .replace(). It did still catch
an injected clock-derived marker, but it passed with the feature deleted. Assert
the dates are present.
4. The malformed-date check ran only over the active set, exempting archive
records. Staleness is moot there, but a typo is still a typo — check both wings.
Adds regression tests for each, plus a Review-due row for a topic-file record
(pinning the `../decisions.md` vs bare-filename link forms).
Evaluated the Open Knowledge Format (GoogleCloudPlatform/knowledge-catalog okf
v0.2, scaccogatto/okf-skills) as a replacement for our decision-record system and
rejected it: its conformance rules are deliberately permissive exactly where ours
are strict (broken links, unknown types and missing fields must all be tolerated;
`deprecated` points at no successor), and its stable identity is the file path,
which the breadcrumb rule tells agents not to trust.
Adopted two of its optional families instead, additively:
- `stale-after: YYYY-MM-DD` on the metadata line — marks a record asserting an
outside-world fact as due for re-confirmation. Absolute date, no TTL.
- `**Sources:**` in the metadata block — the evidence a record rests on, as
distinct from `Signals:` (recall keywords).
Neither is required; absence is never an error. A malformed `stale-after` is
blocking (it would silently never fire), but a past-due record is only a
non-blocking `::notice::` — going stale is the passage of time, not a defect in
whatever commit is under test. The catalog's new "Review due" section renders the
date only and never a clock-derived verdict, so it cannot drift `--check` red on a
calendar boundary with no commit touching the corpus.
No backfill: no existing record adopts either field here.
fixes#603
Adds scripts/decisions_lib.py, the shared parser for ErsatzTV decision
records (docs/decisions.md + docs/decisions/*.md). Parses H2 sections
into Record dataclasses, distinguishing migrated records (visible
metadata block: key/status/since/supersedes/superseded-by + Rule/
Signals/Mechanics) from legacy-unmigrated ones with no metadata line.
scripts/ is now an importable package (scripts/__init__.py,
scripts/tests/__init__.py) so later tools can `import scripts.decisions_lib`.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>