Letta AI Agent
Platform for stateful agents: AI with advanced memory that can learn and self-improve over time.
Letta is an open-source ai agent by letta-ai, with 25,315 GitHub stars and the Apache-2.0 license. Its code was last updated Oct 18, 2026. The latest npm release is @letta-ai/letta-code 0.34.62, published Nov 15, 2026, with 73,465 downloads last week.
Letta
Build stateful agents with memory that can learn and improve over time.
Letta (f.k.a. MemGPT) is actively developed. The current source code lives in letta-ai/letta-code, which includes the agent harness, interactive terminal UI, App Server, channels, and the runtime used by the desktop and web apps.
Get started
Install Letta from npm:
npm install -g @letta-ai/letta-code
Launch the interactive terminal UI:
letta
Run the App Server for local or self-hosted agents:
letta server
You can also use Letta through:
- chat.letta.com in your browser, including on mobile
- Slack, Telegram, Discord, and custom channels
- the Letta Agent SDK for building agents into TypeScript applications
- Letta Cloud for keeping agent memory, identity, and conversations available across computers
See the Letta documentation for current installation, development, and deployment instructions.
Historical source
The archive branch contains the retired Letta V1 API server. Existing tags and releases remain available for reproducibility, but active projects should use the current source.
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| Name | Stars | Licence | Last updated | Scan |
|---|---|---|---|---|
| Letta (this page) letta-ai | 25k | Apache-2.0 | Oct 18, 2026 | Scanned, no flagged issues |
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