C4. `coverage` gains two keys, and every key it had keeps its bytes:
- `absent_terms`: the question's words the bundle holds in NO form -- not as
written, and not through a relative it uses (`bm25.query_groups`, the same
bridge the ranking reads through);
- `weak`: true when one such word exists or nothing was delivered.
A reading with its rule in the open, never a verdict about the bundle. It is
computed for both rankings (`bm25.absent_terms` serves the fusion). The
retrieval gate's `marked` -- the one reading both gates share -- reads `weak`
beside its own bar, never instead of it; the known-negative that strips the
payload's words now strips both readings.
Words that only FRAME a question are stopwords in both languages (`how
often`, `hvor ofte`, `hva står i`, `what does it say`), and so are the
Norwegian function words spelled without their letters (`naar`, `paa`), the way
ASCII-only text writes them. Read as topic words they would be "absent" from
any collection that never uses them, which is what the synthetic sets showed
on three answered questions before the list was extended.
The working method says what to do with it, in one sentence each: the skill
template's step 3 and the MCP server's instructions (1 253 bytes, under the
2 048 a client keeps) -- rephrase in the bundle's words, and if it stays weak,
say the bundle does not cover the question.
The search gate's table for this commit is kept in local state.
Suite on a clean tree after `git add`: 2397 passed, 2 skipped, 4 xfailed.
ruff, ruff format, mypy --strict clean. Retrieval gate unchanged at the rows
the previous commit left red.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
C1. `okf consume` and MCP's `okf_ask` now rank with BM25 (`bm25.py`) instead
of the three-signal fusion. Two signals, fused by reciprocal rank:
- passage: every body cut into 500-character windows every 250, a concept
scored by its BEST window -- a narrow question is answered in one place;
- field: title three times, the id path and source name twice, then the body
-- a broad question is answered by what a section is called.
The document prior and the rarity weight are gone from the default: the first
favoured big documents full of common words, the second gave its largest
weight to a word the collection does not hold. Under BM25 such a word weighs
exactly zero. A signal that scores a concept zero adds nothing to it, and ties
share a rank, so alphabetical order lifts nothing either.
Three rules carried over from the fusion, each with its own test, because the
suite showed what BM25 alone lost:
- a directory every concept shares is not read (K3-20's defect, one signal on);
- a number a section is known by (`4.2`, `10.2-2`) is kept as one token, or
a question naming a section by its number matches nothing in it;
- a question word the collection does NOT hold is read as the collection's
words it shares a leading word with (`consume.tokens_match`) -- Norwegian
inflection and compounding -- at that word's idf, never at its own.
The lookup and title-covered partitions are shared with the fusion
(`_partitioned`). `ranking="fusion"` / `--ranking fusion` keeps the old order
reachable; `--cost-vocabulary` and `--rarity-weight` widen only the fusion and
are refused with the default (`ranking_flag_conflict`) rather than ignored.
C3. A concept longer than `PASSAGE_CHARS` (4 000) is delivered as the span
around its best window, snapped to whole lines, under the nearest heading
above it, with `[...]` where text was left out. `passage: {start, end, of}`
says so, `text_sha256` covers what was delivered, and `sha256` stays the
file's, so the whole can be fetched by `concept_id`. 4 000 because eight
excerpts of it stay far under a tool response's limit even with several
sub-questions merged, while a 500-character window keeps 3 500 characters of
surroundings. The budget pays for the passage, not the file.
Tests moved with the default, each stated rather than silenced:
- fusion-mechanism tests (cost vocabulary, rarity weight, reservation, shared
rank, the reference-bundle pins) ask for `ranking="fusion"`, the order they
were measured on; the BM25 reading of the reference bundle is a separate
measurement, kept in local state;
- the retrieval gate still measures the shipped default. Row 1 holds. Four of
its premises were built against the fusion (a concept forced below k that
BM25 now delivers, a quota that no longer decides, mutants patching fusion
code) and are `xfail(strict=True)` until the fixtures are re-measured;
- the shipped example payload is regenerated; the shipped skill is unchanged.
README's Consume section and CLAUDE.md state the new default and that the
flags described after it belong to the fusion.
The search gate's table for this commit is kept in local state: the question
sets belong to a consumer whose content does not go on a public mirror.
Suite on a clean tree after `git add`: 2390 passed, 2 skipped, 4 xfailed.
ruff, ruff format, mypy --strict clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
