Runs #003-#009 surfaced the same finding: fresh workers added
mid-run to the main 'workers' vectord index (5K items) reliably
*absorbed* (HTTP 200) but failed to *surface* in semantic queries
even with content-matching prompts. Distances on the verify queries
sat at 0.25-0.65 against existing workers; fresh items were beyond
top-K. Better embedder (v2-moe) didn't help — distances got TIGHTER
on existing items, pushing fresh items further out of reach.
Root cause: coder/hnsw incremental adds to a populated graph land
in poorly-connected regions and disappear from search traversal.
Known property of HNSW post-build adds; not a bug.
Fix: two-tier index pattern (canonical NRT search architecture).
Fresh content goes to a small "hot" corpus (fresh_workers); main
queries include it in the corpora list and merge results. Hot corpus
has no recall crowding because it's tiny; periodic batch job (post-
G3) merges it into the main index.
Implementation:
- ensureFreshIndex(hc, gw, name, dim) — idempotent POST
/v1/vectors/index. 409 from re-create treated as "already there."
- ingestFreshWorker now takes idx parameter so callers can target
fresh_workers instead of workers.
- multi_coord_stress phase 1b creates fresh_workers index + ingests
3 fresh workers there + searches verifyCorpora=[workers,
ethereal_workers, fresh_workers].
Run #010 result:
fresh-001 (Senior tower crane rigger NCCCO Chicago)
top-1: fresh-001 from fresh_workers, distance 0.143
fresh-002 (Bilingual Spanish/English OSHA trainer Indianapolis)
top-1: fresh-002 from fresh_workers, distance 0.146
fresh-003 (FAA Part 107 drone surveyor Chicago)
top-1: fresh-003 from fresh_workers, distance 0.129
3/3 fresh workers surface at top-1 — the absorption-but-not-
findable issue from runs #003-#009 is closed.
All other metrics held: diversity 0.007, determinism 1.000,
verbatim handover 4/4, paraphrase handover 4/4, swap Jaccard 0.000,
inbox burst all 6 events accepted + traced to Langfuse.
This is the final structural fix for the multi-coord stress
suite. Phase 3 is feature-complete.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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