open/llm-ingestion-okf
1
0
Fork 0
Code Issues Releases 1 Activity

docs(k3): round 22, frontmatter a YAML reader reads back the same

Browse source 
K3-22's report, CHANGELOG under [Unreleased], and two corrections of a
sentence measured false.

README and CLAUDE.md both said of the flow form "both are valid YAML, and a
real YAML consumer recovers the same structure from either". An unquoted URL
with a query string inside a flow mapping is not valid YAML for PyYAML, and
the quoted form is refused by the pinned guard; the paragraph now states the
limit. CLAUDE.md also records the K3-22 invariant and the new refusal of a
`--frontmatter` flow value with such a leaf.

Measured, fix `ed0418f` against base `0308169`, each tree built twice from
frozen exports: five-document project 0 files moved; R761 XML and HTML 1 line
each; K2 default 42 `title` lines, after which 454 of 454 frontmatters parse
and read back the same (base 413 parse, 412 read back). hit@k on R761 base =
fix, S1-S6 6/6 at hit@1/8/50 at both k, KP rank 1; okf check 32 of 32 payloads
0 findings over 16 rules; K2 pin 7 passed in the export.

Found outside the order: the pinned guard refuses nearly every segmented
concept okf writes, on its scalar flow sequences (`source_offset`,
`references`, `derived`) -- identical before and after, so older than K3-22.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
Kjell Tore Guttormsen 2026-09-11 11:47:40 +02:00
commit e717b1c87a
4 changed files with 350 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

285
docs/2026-09-11-k3-runde22-yaml-lesbar-frontmatter.md Normal file
View file

@ -0,0 +1,285 @@
# K3 round 22 — frontmatter a YAML reader reads back the same
Order K3-22, 2026-09-11. Red `06e61a5`, fix `ed0418f`, base `0308169`
(v0.8.3). PyYAML 6.0.3, guard 1.3.0, Python 3.14.0 (working tree and the
frozen exports, run through the repository's own interpreter with the export
first on `PYTHONPATH`; `__file__` verified under the scratch export for both).
## Deviations, first
1. **The order's form for the flow mapping cannot ship.** It asked for
`sources: [{ resource: "https://…?x=nb", title: … }]` -- a double-quoted
leaf inside the flow mapping. PyYAML reads that; the pinned guard does not.
Guard 1.3.0 `okf.parse_frontmatter` refuses ANY quote inside a flow mapping
("a quoted scalar inside a flow mapping is not a supported form"), double
or single, measured below. Writing it would have moved 4 605 PyYAML
failures to 4 605 guard failures, and broken the promise
`tests/test_provenance.py` already holds ("what Door B writes must survive
the guard's own frontmatter grammar"). So a flow leaf is VALIDATED, never
quoted: a value no flow form both readers accept is refused with the door's
existing code. Quoting is used where the guard admits it -- a block scalar.
2. **The failure is bigger in this repository's own output than the order's
table shows, and in the other place.** The order's table has no bundle
`okf` built with its defaults. The pinned K2 default bundle fails
`safe_load` on **41 of 455** frontmatter blocks, and **1 more** parses
while PyYAML reads a different value than ours (a title carrying `" #"` --
PyYAML stops at the comment, no error). All 42 are block `title` scalars
(FEIL B); **0** `sources` values okf wrote failed anywhere measured. The
4 605 `?` failures (FEIL A) come from a consumer's own `sources` writer,
which does not go through this library.
3. **The consumer repository is at `f783e52`, not `6fad6a2`.** The hit@k
instrument was taken from `6fad6a2`, as ordered, into private scratch with
the payload path changed (2 lines differ from the original). Its tree was
clean before and after (`git status --porcelain`: 0 lines both times).
4. **The default-`k` hit@k run passes four flags, not five** (`--bundle
--questions --okf --out`, no `--k`), reproducing how the previous round ran
it; the `k = 50` run passes all five.
## 1. The standard
SPEC (`_okf-canonical` `ad30107`), verbatim:
- **§ 4, opening:** "Every concept is a UTF-8 markdown file with two parts:
1. A **YAML frontmatter block**, delimited by `---` on its own line at the
start of the file and a closing `---` on its own line." (l. 155-158)
- **§ 11, Conformance, point 1:** "Every non-reserved `.md` file in the tree
contains a parseable YAML frontmatter block." (l. 740-741)
**What the spec does not say, and it is a weakness of the spec:** it names no
YAML version and no subset -- 0 hits for a version number, "YAML version" or
"subset", with the query validated against the known-positive `YAML` (5 hits).
"Parseable" is therefore whatever reader the consumer has, and PyYAML is the
common one. That is why the reader, not this corpus, decides the rule.
## 2. The measurement, reproduced
`yaml.safe_load` over the block between the two fences; the denominator is
files WITH a frontmatter block (index files without one are not counted --
e.g. 5 514 `.md` against 2 757 with frontmatter in the first row).
| tree | with frontmatter | OK | FAIL | order's figure |
|---|---|---|---|---|
| consumer R761 (N-route) | 2 757 | 1 | 2 756 | same |
| consumer N100 | 447 | 1 | 446 | same |
| consumer N200 | 1 134 | 1 | 1 133 | same |
| consumer N500 | 271 | 1 | 270 | same |
| consumer R761, built by `okf build` | 2 763 | 2 762 | 1 | same |
| this repository's `tests/fixtures` | 12 | 12 | 0 | same |
| **K2 default bundle (pinned)** | **455** | **414** | **41** (+1 misread) | not in the order |
| R761 HTML build (v0.8.3) | 3 208 | 3 207 | 1 | not in the order |
| R761 XML build (v0.8.3) | 2 763 | 2 762 | 1 | not in the order |
| five-document project (v0.8.3) | 29 | 29 | 0 | not in the order |
| `examples/` · `skills/` | 14 · 3 | 14 · 3 | 0 · 0 | not in the order |
Every figure the order gave reproduces exactly.
## 3. The two causes
**FEIL A -- `?` inside a flow mapping.** The consumer writes
`sources: [{ resource: https://<viewer>/api/…/860019?languageCode=nb, title: … }]`
unquoted. PyYAML's scanner ends a plain scalar in FLOW context at `?`:
```
while parsing a flow mapping ... expected ',' or '}', but got '?'
```
The colon in `https:` is not the cause: `https://h.no/a/1` in the same place
parses.
**FEIL B -- a block scalar written verbatim.** The profile emitter wrote every
value as `key: value`. A title ending in `:` gives
```
mapping values are not allowed here
```
and the K2 bundle adds a leading `- ` ("sequence entries are not allowed
here"), a leading `*` or `**` ("expected alphabetic or numeric character" /
an undefined alias) and `": "` inside a title.
## 4. The constructs, measured
PyYAML 6.0.3 (`BaseLoader`), and guard 1.3.0 `okf.parse_frontmatter`:
| construct | PyYAML | guard |
|---|---|---|
| `sources: [{ resource: https://h.no/a/1?x=nb, title: T }]` | FAIL, `got '?'` | admits |
| `sources: [{ resource: https://h.no/a/1, title: T }]` | OK | admits |
| `sources: [{ resource: a=b&c.pdf, title: T }]` | OK | admits |
| `sources: [{ resource: fil.pdf, title: N100:2023 }]` | OK | admits |
| `sources: [{ resource: fil.pdf, title: N100: 2023 }]` | FAIL, `got ':'` | -- |
| `sources: [{ resource: fil.pdf, title: Kap #3 }]` | FAIL, `<stream end>` | -- |
| `sources: [{ resource: fil.pdf, title: -x }]` | OK | admits |
| `sources: [{ resource: fil.pdf, title: *x }]` | FAIL, alias | -- |
| `sources: [{ resource: "https://h.no/a/1?x=nb", title: T }]` | OK | **REFUSES** |
| `sources: [{ resource: 'https://h.no/a/1?x=nb', title: T }]` | OK | **REFUSES** |
| block `sources:` / `- resource: https://h.no/a/1?x=nb` / `title: T` | OK | admits |
| `title: Eksempel kontur:` | FAIL, mapping values | refuses |
| `title: "Eksempel kontur:"` | OK | admits (keeps the quotes) |
| `title: N100: 2023` · `title: - punkt` · `title: *stjerne` | FAIL | -- |
| `title: Kap #3` | **OK, as `Kap`** | admits |
| `utgave: R761 Prosesskoden:2025` · `title: Kap#3` | OK | admits |
## 5. The form, and why it is the narrowest
**Block scalars: double-quote exactly the values K3-19's rule refuses.** The
rule (`no leading indicator, no ": ", no " #", no trailing ":", no tab or line
break`) is now `profiles.yaml_block_plain`, and over every top-level value in
eleven measured trees it agrees with PyYAML read verbatim on every one: **0
refused that PyYAML returns verbatim, 0 kept that it does not** (K2 5 524
values, the HTML build 38 752, the XML build 35 177, the five consumer bundles
and the rest). Quoting everything would move bytes in every concept of every
bundle and buy no valid file; this moves only the values that were failing.
**Double, never single -- counted.** Values wrapped in a surrounding `"` pair:
**0** in twelve trees (the eleven plus `skills/`). Wrapped in `'`: **11 193**,
all in the consumer bundles (10 937 + 67 + 86 + 103), written that way on
purpose. A reader that unquotes `"` changes the meaning of no value that
exists; one that also unquoted `'` would change 11 193.
**Flow leaves: no quoted form exists, so validation.** Plain fails PyYAML on
`?`, `,[]{}`, `": "`, `" #"`, a trailing `:` and a leading indicator; quoted
fails the guard. `profiles.yaml_flow_plain` is the block rule plus
`,[]{}?'"`, with one exception the block rule does not make: a leading `-`
followed by a non-space, which both readers take (`del/-utkast.pdf`). Refusing
that would refuse a document both read; the block rule keeps refusing it
because it also decides which spec points are written at all, and in a block a
refusal costs only a pair of quotes. The refusal uses each door's existing
code: `inbox_source_file_unaddressable` (also when the FILE NAME, which becomes
the entry's `title`, is not plain), `inbox_source_title_unaddressable`,
`source_reference_unquotable` (Door A), `run_frontmatter_invalid`
(`--frontmatter` with a flow value).
Over a constructed list of 39+ values (in `tests/test_yaml_frontmatter.py`)
the safe direction is required and the over-refusals are pinned: block keeps 0
PyYAML would misread and over-refuses 3 (`-punkt`, `?spm`, `:kolon`, which get
quoted); flow keeps 0 that PyYAML or the guard would refuse and over-refuses 0.
**Readers read both forms.** `materialize.parse_frontmatter`, the index
reader's and the structure reader's copies, and both `read_sources` branches
unquote a `"`-wrapped value, decoding `\"` and `\\` and nothing else. Other
backslash escapes (`\n`, `\t`, `\x..`, `\u....`) are kept as written: the
emitter never writes them. `'`-wrapped values are untouched -- except in the
structure reader, which already unquoted both forms before K3-22 on its own
rule (`version: '2021'` is a string) and keeps doing so. The flow-mapping
split is quote-aware, so `{ title: "a, b" }` is one pair; a `"` opens a quoted
scalar only where a value can start, so a plain value with a `"` in its middle
splits as before.
The generated `SKILL.md` header goes through the block rule too:
`description` carries the root index's `bundle_id` raw.
## 6. What moved bytes, and what did not
Each tree built twice, from the base export and the fix export, and compared
with `diff -rq`:
| build | concepts / md | files that differ | the line |
|---|---|---|---|
| five-document project | 26 / 52 | **0** | -- |
| R761 XML (`--bundle-id r761-prosesskoden-2025 --okf-version 0.2 --ingested-at 2026-09-08T12:00:00Z`) | 2 761 / 5 501 | **1** | a title ending in `:`, now double-quoted |
| R761 HTML, 828 files | 3 206 / 6 015 | **1** | the same section's title |
| K2 default, rebuilt (43 documents) | 453 / 864 | **42** | 42 `title` lines, now double-quoted: the 41 that failed `safe_load` and the 1 that parsed to a truncated title |
The K2 base rebuild is byte-identical to the pinned K2 artefact on every file
but `log.md`, which the corpus harness had not yet written when the two were
compared -- so the 42 lines are K3-22's and nothing else's.
- **Goldens and fixtures: 0 bytes.** The golden tests are byte-exact and pass;
`tests/fixtures` is untouched and still 12 of 12.
- **Readers on existing bundles: 0 differences.** Base readers and fix readers
return identical `parse_frontmatter` and `read_sources` results on **25 273
of 25 273** files across nine trees (the five consumer bundles, the pinned K2
bundle, the HTML and XML builds, `tests/fixtures`). N100/N200/N500 are read
exactly as before.
- **One behaviour moved, and it is a refusal.** `okf build --frontmatter
'sources=[{ resource: <URL with ?>, … }]'` now exits 2 and writes nothing.
Measured on R761 with K3-19's flags: the base export writes **2 761 of 2 761**
concepts PyYAML refuses (2 760 on `?`, 1 on the title), the fix export
refuses the run. Two K3-19 tests built with such an address; they now build
with one without `?`, and a new test holds the refusal.
- **The K2 pin** holds concept count and hit ranks, not bytes, so it did not
need moving: **7 of 7 passed** in the frozen fix export, with the gold set
copied in (without it the pin is 7 skipped, which is not a measurement).
## 7. Acceptance
| check | result |
|---|---|
| PyYAML valid, fix builds | five-document 28/28 · R761 XML 2 763/2 763 · HTML 3 208/3 208 · K2 **454/454** (base 413/454) |
| dict-equal to `parse_frontmatter` + `read_sources`, every file | 28/28 · 2 763/2 763 · 3 208/3 208 · K2 **454/454** (base 412/454) |
| generated `SKILL.md` headers, `safe_load` | **4 of 4** (five-document, R761 XML, HTML, K2) |
| hit@k R761, base = fix | S1-S6 hit@1/8/50 **6/6 · 6/6 · 6/6** at default `k` and at `k = 50`; KP rank **1** at both; KN not delivered at both |
| `okf check` on every payload | **32 of 32** exit 0, "conformant: 16 rules … 0 findings" (`len(RULES)` = 16) |
| `grep -rc "import yaml" src/` | **0 on each of 22 files** |
| `[project.dependencies]` | unchanged, `["llm-ingestion-guard>=1.2,<2.0"]`; `uv.lock` +2 lines, the dev dependency |
| suite, working tree | 1 667 passed / 1 skipped before; **1 753 / 1** after (85 + 1 new) |
| suite, frozen fix export from a scratch cwd | 1 750 / 1 / 3 failed: the two known (`test_segmented_golden` four-goldens, `test_guard_adapter` cwd-relative path) and `test_cli_build::…installed_copy`, which fails identically on the base export under this runner -- the runner's `PYTHONPATH` reaches the subprocess the test installs into |
The hit@k base row reproduces the previous round's before anything else was
read.
## 8. Found, and outside this order
**The guard's parser refuses nearly every segmented concept okf writes, for a
reason that is not YAML.** Guard 1.3.0 admits a flow sequence of MAPPINGS only
("a flow sequence admits flow mappings only"), and okf writes scalar flow
sequences at top level: `source_offset: [1, 24]`, `source_lines`,
`source_pages`, `derived: [references]`, `references`. Measured with
`okf.parse_frontmatter` over whole frontmatters: five-document 26 of 28
refused, R761 XML 2 761 of 2 763, HTML 3 206 of 3 208, pinned K2 412 of 455 --
identical on base and fix, so it predates K3-22. PyYAML reads all of them.
What this means for Door C importing an okf bundle is **not measured** here
(`import_bundle` was not run).
## Honesty limits
- **PyYAML is one reader.** The rules are validated against it and the guard;
a YAML 1.2 reader accepts more (`?` inside a flow scalar), so the rules are
stricter than 1.2, never looser than PyYAML on the values measured.
- **The flow-collection exemption trusts its producers.** The emitter writes a
value shaped `[...]` or `{...}` as it stands. Over the eleven trees only
structural keys carry that shape and no `title` does; a producer that built a
malformed collection would still be written. The run-stated route
(`--frontmatter`) is validated; the internal producers are measured, not
checked at emission.
- **Two escapes.** `\"` and `\\` are written and decoded; any other escape is
neither.
- **The 217 descriptions stay omitted.** A derived spec point carrying `": "`
is still not written (K3-19), although it could now be written quoted.
Writing it would add values, which this order excluded.
- **The constructed list is constructed.** The "0 / 0" over real values is the
measurement; the constructed list pins the directions on shapes the corpora
may not carry.
- **Conformance is the floor, never the proof.** § 11 point 1 now holds on
every build measured; that says the frontmatter parses, not that a bundle is
good.
## Corrected
`README.md` said of the flow form: "both are valid YAML, and a real YAML
consumer recovers the same structure from either". Measured false: an unquoted
URL with a query string inside a flow mapping is not valid YAML for PyYAML.
The paragraph now states the limit, and `CLAUDE.md` carried the same sentence
and is corrected with it.
## Reproduce
```sh
# PyYAML validity, denominator = files with a frontmatter block
python3 - <<'EOF'
import sys, yaml, pathlib
root = pathlib.Path(sys.argv[1] if len(sys.argv) > 1 else ".")
fm = ok = 0
for p in root.rglob("*.md"):
lines = p.read_text(encoding="utf-8").splitlines()
if not lines or lines[0].strip() != "---":
continue
fm += 1
try:
yaml.safe_load("\n".join(lines[1:lines.index("---", 1)])); ok += 1
except yaml.YAMLError:
pass
print(f"with frontmatter={fm} ok={ok} fail={fm - ok}")
EOF
```