Letta (MemGPT)

Partial info

Stateful agents with long-term memory (MemGPT).

Letta, from the creators of MemGPT, is an open-source (Apache-2.0) framework and service for building agents with persistent long-term memory and reasoning that survives across sessions. It offers self-hosting and a managed cloud.

License

Open source (Apache-2.0)

Deployment

Self-hosted, Managed

Pricing

Open-source; Letta Cloud is usage-based.

SDKs / languages

Python, TypeScript

Founded

2023

Strengths

First-class long-term memory
Agents persist across sessions
Open-source with cloud option

Limitations

Narrower than general frameworks
Memory model adds complexity

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Facts verified 19 July 2026. Neutral summary, not an endorsement; verify current details with the vendor.