Letta
Open-source agent harness for stateful agents whose memory persists and improves with use, with a terminal UI, app server and TypeScript SDK.
Harness by Letta
Install
From the package registry. Read the repository before you give any tool access to your data.
pip install letta
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About
Use cases: agent-memory, agent-orchestration
Reviews
Write a reviewNo reviews yet. Installed it? Reviews come from verified installers only. How reviews work
Fact sheet
- Languages
- TypeScriptREADME
- Packages
- letta (pypi), @letta-ai/letta-code (npm)README
- Memory
- long-termdocs.letta.com
- Deploys to
- letta-cloud, self-hosteddocs.letta.com
- Maturity
- Betagithub.com
Facts extracted by Claude Sonnet 5.5 from the linked sources on Oct 24, 2026; reviewed Oct 24, 2026. Wrong fact? Tell us.
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Featured in
Signals
- Stars
- 25,244
- Forks
- 2,656
- Open issues
- 0
- Weekly downloads
- 40,711
- Last commit
- Oct 18, 2026 (8 days ago)
- Last release
- May 14, 2026 (5 months ago)
- Last package publish
- Oct 23, 2026 (3 days ago)
From GitHub (fetched Oct 24, 2026) and the package registry.
Details
- Packages
- pypi
lettanpm@letta-ai/letta-code - License
- Apache-2.0
- Repository
- github.com/letta-ai/letta
- Website
- www.letta.com/
- Docs
- docs.letta.com/
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
More from Letta
- 0.826score
Letta
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Platform for stateful agents that learn from experience and keep their memory across sessions.
InfrastructureAFreshness: A★ 25.2Kmemory - 0.659score
Letta Code
Letta
Stateful agent harness whose agents keep memory across sessions and run on schedules through a CLI, browser and chat apps.
AgentAFreshness: A★ 3.7K
Cite this page
Letta. Agent Mart. https://agentmart.dev/harnesses/letta (last updated 2026-10-24)