Agent FrameworksOpen Source✦ Free Tier

Letta

Stateful agents with long-term memory — formerly MemGPT

13,200 stars● Health 85ActiveApp Infrastructure

About

Letta (formerly MemGPT) is an open-source framework for building stateful AI agents with persistent, editable memory. Agents remember conversations across sessions, search their own memory, and update their knowledge over time — solving context window limitations.

Choose Letta when…

  • need agents with persistent cross-session memory
  • context window length is limiting your application
  • building personal assistants or long-running agents

Builder Slot

How does your AI reason and plan?Recommended for most stacks

The framework that structures how your AI thinks, uses tools, and coordinates agents

Dev Tools
Not applicable
App Infra
Recommended
Hybrid
Recommended

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Stack Genome Detection

AIchitect's Genome scanner detects Letta in your project via these signals:

pip packages
letta
env vars
LETTA_API_KEY
config files
.letta/

Integrates with (1)

OpenAI APILLM Infrastructure

Letta agents use OpenAI models as their reasoning core, extended with Letta's persistent memory layer.

Long-running stateful agents that remember context across sessions without context window limits.

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Alternatives to consider (1)

Pricing

✦ Free tier available
Open SourceFree
Cloud$20/mo

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