- Add dependency-free TF-IDF retrieval (src/lib/retrieval.js) with NL+EN
stopwords and a WeakMap-cached index.
- Rewrite buildKbContext to ship the top-K relevant topics + verbatim-
mentioned ids only, filter relations to the included set, and append a
[kb_hash: <8 hex>] suffix so the ephemeral prompt cache busts when the
graph changes. Returns { context, retrievedTopics, allTopics }.
- Add LOOKUP_TOPIC_TOOL and drive useChat through callLLM directly with a
multi-hop tool_result loop capped at 3 hops; preserve Anthropic-provided
tool_use ids through callLLM so the loop can echo correct tool_use_id.
- Truncate R42 history to the last 12 turns and prepend a single
"(earlier conversation truncated)" assistant message.
- Set R42 chat defaults: temperature 0.3, maxTokens 2048.
- Add pb_migrations/1780500002_created_llm_calls.js (the best-effort
logger in callLLM was already wired) and a new Admin → Diagnostics
view showing the last 100 calls with token usage, cache-hit rate, and
USD cost from a local Anthropic price table.
- Finalize AI_PIPELINE_HARDENING_PLAN.md: mark Phases 1–5 shipped and
Phase 6 (eval harness) explicitly out of scope.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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