Letta

Letta is the open-source platform that transforms stateless LLMs into perpetual, self-improving AI agents with persistent, hierarchical memory.

Letta (formerly MemGPT) delivers the AI Operating System for stateful agents: a critical upgrade for LLMs. The platform, originating from UC Berkeley's Sky Computing Lab, utilizes a hierarchical memory model (core in-context blocks and external archival storage) to ensure agents maintain context across multi-session workflows. Developers build, deploy, and manage these stateful agents using robust Python and TypeScript SDKs, or the Agent Development Environment (ADE). This model-agnostic framework supports local providers (Ollama) and cloud services, enabling long-running, self-improving agents for complex use cases like customer support and research assistance.

https://letta.com