One schema-bump release (recall-index schema 3, entity-index schema 2; old
recall indexes rebuild automatically, no vault migration):
- Local-first recall index: the live BM25 index lives in the machine state dir
(keyed by endpoint hash); capture's upkeep is a zero-network atomic file
write, no advisory lock — replacing the O(vault) GET/PUT-whole-index round
trip per write. The vault copy is a snapshot (sweep + session-end) used to
seed fresh machines / catch up after another client swept
(ECHO_RECALL_SYNC_HOURS, default 24). The read path never PUTs the vault.
- Incremental sweep: entity + recall meta carry 16-char content hashes;
`sweep --fast` fetches only new/gone/hash-missing notes plus a rotating
weekday shard (--all-shards forces everything); deletions drop from both
indexes; index-only so no --apply gate. `load` auto-runs it past
ECHO_FAST_SWEEP_DAYS (7); doctor reports index freshness. Obsidian-side
edits now reach the indexes without manual maintenance.
- Stemming + alias expansion: echo_stem.py (conservative Porter-lite, unit-
tested families + over-stemming guards) applied at index AND query time;
a query fuzzy-matching an entity folds its title/alias vocabulary into the
BM25 query at half weight — expansion can only boost docs containing the
terms. capture hashes the note's FINAL content (auto-link reordered first).
Eval gold set 8 -> 14 queries (6 paraphrases): recall@5/MRR 1.00/1.00 vs
keyword baseline 0.75/0.79. +3 unit tests, +10 e2e; test harnesses now isolate
ECHO_STATE_DIR. All seven suites green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Jason Stedwell