Memory Framework
A dedicated library or service that handles AI agent memory — extraction, storage, reconciliation, expiration, and retrieval — so you don't have to write it yourself. The 2025-26 landscape converged on a handful: [Mem0](https://mem0.ai/) (open source + hosted, personalization-focused), [Letta](https://www.letta.com/) (formerly MemGPT, tiered in-context/archival memory), [Zep](https://www.getzep.com/) (temporal knowledge graph), [Cognee](https://cognee.ai/), and vector-store-native offerings from Redis, Pinecone, and Milvus. LangGraph's checkpoint layer covers working-memory persistence but isn't a full memory framework. See our [memory pillar](/blog/ai-agent-memory-how-it-works/) for the decision matrix.
Frequently asked questions
- When should I use a memory framework vs. rolling my own?
- Roll your own if your needs are simple — last N conversation summaries per user, no fact extraction, no reconciliation. A Postgres table with (customer_id, timestamp, summary, structured_facts JSONB) covers most support agents. Move to Mem0 / Letta / Zep when your reconciliation logic (which fact wins when two contradict) or dedup logic starts eating engineering hours, or when you need semantic search over episodic memory at scale.