# Letta (formerly MemGPT)

> Stateful agents with persistent memory that learn and improve over time, formerly MemGPT.

## Facts
- **Category:** [Agent Frameworks](https://agentsearchengine.app/category/agent-frameworks)
- **Type:** Framework
- **Pricing:** Open source
- **GitHub stars:** 24,852
- **License:** Apache-2.0
- **Last repo activity:** 12 days ago (Sep 10, 2026)
- **Official site:** https://docs.letta.com/
- **Source code:** https://github.com/letta-ai/letta
- **Listing on Agent Search Engine:** https://agentsearchengine.app/agents/letta
- **Data verified:** September 2026

## Best for
Assistants that need long-term, self-editing memory rather than a fresh context each session.

## About Letta (formerly MemGPT)
Letta, formerly MemGPT, builds stateful agents whose memory persists and improves across sessions. Current development lives in letta-ai/letta-code, which contains the agent harness, terminal UI, App Server and channel integrations; agents are also available through desktop apps, a web app, Slack, Telegram and Discord, a TypeScript Agent SDK and Letta Cloud. This repository keeps the project's history.

## Install

```
npm install -g @letta-ai/letta-code
```

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Source: [Agent Search Engine](https://agentsearchengine.app) — an independent, hand-curated index of AI agents, MCP servers, and frameworks. Rankings are never sold; sponsored placements are labeled and never numbered. Full directory: https://agentsearchengine.app/llms-full.txt