Elastic built a persistent agent memory layer on Elasticsearch with 0.89 recall

We built a persistent agent memory layer on Elasticsearch with 0.89 recall

Elastic open-sourced an agent memory architecture using three Elasticsearch indices for episodic, semantic, and procedural memory. Hybrid retrieval with a reranker hits R@10 of 0.89 across 168 questions, with zero cross-tenant leaks via per-user DLS. The post doesn't disclose latency or cost figures, but it details design choices: supersession over deletion for audit trails, decay so older facts don't outrank fresh ones, and consolidation of raw events into durable facts. Full implementation is on GitHub.

Why it matters: Elastic open-sourced a persistent agent memory layer with three indices, hybrid retrieval, and a reranker hitting 0.89 R@10. Solid architecture with code, but ES-ecosystem lock-in limits broader appeal — lands right at the featured threshold.