Affiliate link. Joute earns a commission at no extra cost to you. Our verdict stays independent.
Le cron de tracking demarre lundi prochain a 6h UTC. Joute scrape hebdomadairement les pricing pages de cet outil et trace les variations sur 12 mois.
Donnees disponibles des la premiere capture. Revenez lundi.
Letta in brief
Letta (ex-MemGPT) is the reference for building AI agents with persistent memory. If you're building agents that need to remember context across long sessions, Letta solves this hard problem with a solid architecture.
- PricePay as you go
- CategoryAgents IA
- RecommendedYes
The essentials in 20 seconds
- Open source platform for AI agents with persistent long-term memory
- Architecture inspired by OS memory management (virtual pages)
- Formerly MemGPT, rebranded as Letta in 2024
- Price: free open source, cloud pay as you go
Verdict: Letta solves one of the hardest problems in agent development: persistent memory beyond the context window. It's a research-grade tool that has reached production maturity. Essential for long-lived agents.
What is Letta
Letta (formerly MemGPT) is a research and production platform for AI agents with memory. The project came out of UC Berkeley and was published in an influential paper in 2023.
The core idea: simulate paged memory (like OSes) for LLMs, letting agents remember information over indefinite periods by intelligently managing what's kept in active context vs stored in external memory.
Strengths
Solid persistent memory
This is the core of the product. A Letta agent can remember a conversation from 3 months ago, retrieve information from its long-term memory, and maintain a coherent state across thousands of interactions.
Open source with solid research base
The MemGPT paper was widely cited and replicated. The architecture is well understood and documented. The code is maintainable and extensible.
Python/TypeScript APIs and SDKs
Letta offers SDKs to integrate agents into applications. The API is well documented. For an agentic engineer, setup is fast.
Limits
Configuration complexity
Understanding Letta's memory architecture requires reading the paper or in-depth documentation. Not a plug-and-play tool for beginners.
Performance on large memory bases
On agents with thousands of interactions in memory, searches can slow down. Memory optimization is a real topic at scale.
Pricing
- Open source: free (self-hostable)
- Letta Cloud: pay as you go
Alternatives
- LangChain for building agents with basic memory
- LlamaIndex for RAG and document context management
- Mem0 for persistent memory as a simple service
Verdict
Letta is the natural choice for teams building AI assistants or agents that need to maintain context over long periods. The solid research base and open source make it a lasting choice.
FAQ
Does Letta work with Claude and GPT-4?
Yes. Letta supports multiple LLM providers via an abstraction layer.
Is the migration from MemGPT to Letta complex?
Letta is the direct continuation of MemGPT. The migration is documented on the GitHub repo.
Can you use Letta for a customer service chatbot?
Yes, it's a common use case. Persistent memory helps maintain the context of previous interactions from the same customer.
Joute may earn a commission if you sign up via our links. Learn more about our affiliate policy.
Screenshots Letta
8
Letta : 0/10.
Letta (ex-MemGPT) is the reference for building AI agents with persistent memory. If you're building agents that need to remember context across long sessions, Letta solves this hard problem with a solid architecture..
Test Letta yourself
A free trial is available. Plan thirty minutes to form your own opinion.
Affiliate link. Joute earns a commission at no extra cost to you. Our verdict stays independent.
Letta
Pay as you go