Letta is a model-agnostic platform and REST API for building stateful agents whose memory and identity persist across processes and machines. It provides memory blocks, server and client-side tools, approval flows, MCP support, cloud deployment, and official Python and TypeScript SDKs for creating and resuming agents.
Overview
Websitewww.letta.com
Authapi key
PricingFree tier available · $0 self-hosted; cloud usage-based
SDKspython, typescript
OpenAPIYes
MCP SupportYes