engram_search_json ranked its lexical leg by raw distinct-token coverage with
salience as tiebreak: a token in 30,000 nodes counted the same as a token in 1,
and a 1.3 MB record matched nearly every query token by surface area alone.
Score it BM25-shaped instead - Lucene-form IDF and length normalisation over
the corpus mean - with per-token document frequency accumulated in the SAME
corpus pass that finds the hits (no extra scan, no extra round-trip).
Also refuse to return records whose identifier is not printable ASCII. This
corpus carries 1,032 such records (453 by the printable test) from a save-side
corruption; they occupy 125 of 303 returned slots on main. Claims 12, 23 and 27
all key on the node identifier, so such a record is unfetchable by any caller.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Tim Lingo
9c39084e60