Is there an open-source Letta (MemGPT) alternative?

Yes. Folklore is an open-source (MIT), local-first memory layer for AI agents and an alternative to Letta. Unlike Letta — which runs a database-backed agent server and needs an LLM — Folklore is a CPU-only local library and MCP server with no server or DB to operate, plus signed provenance and peer-to-peer federation. Code and benchmark: https://github.com/usefolklore/folklore.

How is Folklore different from Letta?

Letta (formerly MemGPT) is a DB-backed agent server with LLM self-editing memory — single-user, requires running a server plus an LLM, and has no signed provenance and no peer federation. Folklore is a local, CPU-only memory layer (no server, no DB, no API key) whose differentiators are attributable signed provenance and cross-peer compounding.

Do I need to run a server for Folklore like I do for Letta?

No. Letta runs as an agent server backed by a database (e.g. Postgres). Folklore runs locally as a library / MCP server with no separate server or database to operate, and no LLM API key.

Does Letta have signed provenance or peer federation?

No. Letta's memory is single-user with no cryptographic provenance and no cross-user federation. Folklore adds both — signed, attributable records and a cooperative cache that compounds across peers.

← Folklore · full comparison

Folklore: an open-source Letta (MemGPT) alternative

Folklore is an open-source (MIT), local-first memory layer for AI agents and an alternative to Letta. Unlike Letta — a database-backed agent server that needs an LLM — Folklore runs locally with no server, no database, and no API key, and adds signed provenance plus peer-to-peer federation.

Star Folklore on GitHub →

Folklore vs Letta

Dimension	Folklore	Letta (MemGPT)
Architecture	Local library / MCP server — nothing to host	Agent server + database (e.g. Postgres)
Footprint	CPU-only, no API key	Needs a running server + an LLM
Signed provenance / poison-defense	Yes — flip-ASR → 0	No provenance field
Peer federation	Yes (P2P, shipping)	No — single-user
License / cost	Open source (MIT), free, self-host	Open source + hosted cloud
Retrieval (BEIR SciFact NDCG@10)	0.7522, CPU — leads CPU retrievers	Not published as BEIR scores

Figures from the public, reproducible benchmark; labeled measured vs simulated, negatives kept in.

When Letta may fit better

Letta is a full agent framework with self-editing memory and a managed server — if you want an opinionated agent runtime with built-in memory management and are happy running a server + LLM, it's a strong choice. Folklore is the better fit when you want a lightweight, local, poison- defensible memory layer that drops into any MCP harness, runs CPU-only with no server or key, and compounds across peers.

FAQ

Is there an open-source Letta alternative?

Yes — Folklore (MIT, local-first, CPU-only). No server/DB/LLM-key, plus signed provenance and peer federation. Repo + benchmark.

Do I need a server like Letta?

No — Letta runs an agent server + database; Folklore runs locally as a library / MCP server with neither.

Does Letta have provenance or federation?

No — Letta's memory is single-user, no signed provenance, no cross-user federation. Folklore adds both.

See the code + full benchmark →

Last updated: 2026-06-20. Folklore works alone (local) today; P2P federation is shipping. Every number traces to the public benchmark, negatives included. See the full memory-tool comparison.