# Letta

> Episodic memory for agents that think across sessions

**Category:** AI Agents  
**Pricing:** open-source  
**URL:** https://letta.com  
**GitHub:** https://github.com/letta-ai/letta  
**Added:** 2026-08-19

---

## The Hook

Letta gives agents memory that pages in and out like an operating system.

## What's Good

Letta (formerly MemGPT) pioneered the operating-system approach to agent memory. Instead of stuffing everything into context, it pages older information in and out of the working window, letting agents maintain coherent threads across sessions that would otherwise exceed context limits.

## The Catch

More complex to reason about than simple vector retrieval. The paging mechanism adds latency and orchestration overhead. Documentation assumes understanding of the original MemGPT paper.

## Verdict

The memory architecture for agents that need to think long-term.