RetainDB
Hybrid retrieval memory with quality filtering for coding agents.
RetainDB is an open-source AI memory database for coding agents — local-first hybrid vector + BM25 retrieval with built-in noise filtering for cross-session context.
Official resources
Selection advice
What is RetainDB?
RetainDB is a local-first AI memory database built for coding agents. It stores cross-session context with hybrid vector + BM25 retrieval, reranking, and signal-based noise filtering so agents recall useful facts instead of chat clutter.
If you searched for "retaindb", you likely need the product overview, official docs at retaindb.com/docs/intro, or pricing for the hosted cloud option alongside the Apache-2.0 SDK.
Quick comparison
RetainDB targets coding-agent memory with hybrid retrieval and noise filtering. Mem0 and Zep are broader agent-memory platforms with stronger hosted product paths.
| RetainDB | Mem0 | Zep | |
|---|---|---|---|
| Best for | Coding agents needing filtered cross-session memory | General agent memory with fast SDK adoption | Graph-backed memory with hosted platform options |
| Retrieval style | Hybrid vector + BM25 + reranking | Memory layer with flexible retrieval policies | Knowledge graph + semantic retrieval |
| Tradeoff | Narrower ecosystem than Mem0/Zep | Less opinionated about coding workflows | Heavier platform surface for simple prototypes |
Best for
- hybrid retrieval
- session handoffs
- memory quality filtering
Not ideal for
- simple key-value caching
- teams that don't need noise filtering
Core concepts
Minimal implementation shape
Capture and structure agent memories with hybrid retrieval, filter by signal relevance, and hand off session context across coding agents.