# Letta

Letta (formerly MemGPT) is an open-source framework for building stateful AI agents with persistent memory, enabling agents that remember past interactions, learn from experience, and maintain consistent personas over long conversations. Unlike stateless chatbots that forget context between sessions, Letta agents maintain structured memory including core identity, conversation history, and learned knowledge, updating their memory intelligently as they interact. The framework provides a deployment server, REST API, and management tools for running production agent services with full memory persistence.

## Quick facts

- Categories: AI Agents, Developer Tools
- Pricing: Free
- Free plan: Yes
- Official site: https://letta.ai
- Last checked: 2026-10-27

## Key features

- Persistent multi-session memory
- Structured memory management
- Memory update and reflection
- REST API deployment
- Persona consistency

## Use cases

- Long-term AI companions
- Personalized learning assistants
- Customer relationship agents
- Stateful enterprise AI assistants

## Links

- Nextool.ai page: https://nextool.ai/tools/letta-ai/
- Alternatives: https://nextool.ai/alternatives/letta-ai/

Source: Nextool.ai (https://nextool.ai/tools/letta-ai/). Pricing and features change; confirm on the provider's site before relying on them.