Skip to content

v1.2.2 — 75.0% LongMemEval, 52.2% LifeBench

Latest

Choose a tag to compare

@AlekseiMarchenko AlekseiMarchenko released this 20 Apr 12:51

New benchmark results and documentation parity. Central Intelligence's v2 hybrid retrieval pipeline (pgvector HNSW + BM25 + RRF fusion + bge-reranker-v2-m3 cross-encoder) scores among the top results published on both LifeBench and LongMemEval.

Benchmark Results

LongMemEval (ICLR 2025) — 75.0%

Conversational memory across 500 questions: single-session recall, multi-session reasoning, temporal reasoning, knowledge updates, preference tracking.

Overall Single-session Multi-session Temporal Preference
75.0% 91.9% 66.2% 69.9% 76.7%

Answer model: gpt-5.4-mini. Judge: gpt-4o.

LifeBench (2026) — 52.2%

Long-term multi-source memory: 2,003 questions across 10 users, 51K real-world events (messages, calendar, health records, notes, calls). The hardest published memory benchmark.

Overall Info Extraction Multi-hop Temporal Nondeclarative
52.2% 47.2% 52.9% 46.4% 64.1%

Answer model: gpt-5.4-mini. Judge: gpt-4.1-mini.

Evaluation harness: lifebench-eval.

What Got Us Here (since v1.2.1)

The journey from v1.2.1 to v1.2.2, measured on LongMemEval:

Change Delta
Reranker upgrade: MiniLM → bge-reranker-v2-m3 + top-K=10 ~+18pp
Answer model: gpt-4o-minigpt-5.4-mini ~+5pp
Answer prompt: CoT counting + factual precision + multi-hop grounding ~+3pp
Infrastructure fixes (ef_search, performance CPU, 4GB RAM) enabler

Attribution is approximate — each step was measured through the benchmark's run-to-run variance. The architecture that reached 75% is the clean v2 pipeline: pgvector HNSW + BM25 with RRF fusion, temporal decay, and a cross-encoder reranker. No fact extraction or graph traversal during recall.

Changes Since v1.2.1

Retrieval

  • Upgraded reranker to bge-reranker-v2-m3 (8K context, +14% nDCG@10 over MiniLM)
  • top-K=10 retrieval (NeurIPS 2024 finding: accuracy saturates at k=10, degrades with more docs)
  • Set hnsw.ef_search = 400 globally (was silently capped at ~40 results)
  • Reverted to v2 architecture (vector + BM25 + reranker) — removed query decomposition and fact-path that regressed multi-session scores

Benchmark infrastructure

  • Added --answer-model parameter to benchmark entrypoint
  • Performance CPU on benchmark VM (fixes extraction stalls under shared-CPU throttling)
  • DB-driven extraction queue (removed in-memory queue that caused zombie processes)

Documentation

  • README Benchmarks section now includes full category tables for both LifeBench and LongMemEval
  • Landing page at centralintelligence.online matches README numbers exactly
  • Answer/judge model attribution documented inline for reproducibility

Try It

npx central-intelligence-local signup

Full docs: README · Benchmarks: live results