Letta

Stateful AI agents with persistent long-term memory

Code & DevelopmentFree

Letta (formerly MemGPT) is an open-source framework for building stateful AI agents that maintain long-term memory across conversations. It provides a memory management system that lets agents remember facts, relationships, and past interactions indefinitely. Research teams and developers use Letta to build agents that truly learn from ongoing interactions.

Key Features

• ✓Persistent long-term memory
• ✓In-context memory management
• ✓Tool and function calling
• ✓REST API server
• ✓Open-source and self-hostable