How ModelBrain compares
Almost every "best AI memory tool" article on the internet is a vendor ranking itself first. We'd rather you compare on three things that actually predict whether you'll be happy with a memory tool a year from now: where your data physically sits, what happens when you tell it to forget something, and what either project can actually show you about recall quality — not what it claims.
Every claim about another product below cites that product's own dated documentation at publish time. We're not neutral — we built ModelBrain — so don't take our word for the "maturity" row either: we're a working prototype with no release yet, and that's a real disadvantage against tools people already run in production.
ModelBrain vs. Mem0
Shape
A memory layer only, one binary, over MCP. No hosted default.
A memory API and platform, offered self-hosted or as a managed hosted service — check which mode a given doc page assumes.
Where data lives by default
Your own disk. No account exists until you opt into a paid tier.
The hosted tier is the path most people start from, which means an account and a vendor-held copy from the first request unless you deliberately self-host instead.
Forgetting
Two documented behaviors — revert or tombstone — and deletion integrity is a hard-fail line in our published eval, not a scored metric.
Supports updates and deletion; read their docs for the exact guarantee around whether a superseded memory can resurface in retrieval.
Recall-quality evidence
Published adversarial methodology and a reproducible harness that accepts any MCP backend. Results not published yet.
Publishes its own benchmark comparisons. We'd rather you run one harness against both than trust either vendor's numbers, including ours.
Maturity
Working prototype. No release, no track record yet.
Shipping today, funded, an established user base and integrations.
ModelBrain vs. Letta (MemGPT)
Shape
A memory layer only. No agent runtime of its own.
A stateful agent framework with memory as one part, plus a hosted service and its own agent abstractions.
Where data lives
Local vault by default, no account, no identity generated at install. Server storage is a separate opt-in tier.
Self-hostable, and also offered as a managed cloud service — check which mode their docs assume for the feature you want.
Delete semantics
forget has two documented behaviors, revert and tombstone, and deletion integrity is a hard-fail line in our eval.
Memory blocks are editable by the agent itself. Read their docs on who can rewrite a block and what survives that.
Recall-quality evidence
Published adversarial methodology and a reproducible harness. Results not published yet.
Published research lineage from the MemGPT paper. Compare that to our harness directly — it takes any MCP backend.
Maturity
Working prototype. No release, no track record, small number of tested hosts.
Shipping, funded, sizeable community, years of public history.
Pick one of them if
You want a hosted service you don't have to run yourself, or an agent framework rather than a memory layer, or something that ships today with years of production use behind it. Those are real, and ModelBrain doesn't have an answer to "track record" yet.
Pick ModelBrain if
You already have an assistant you like and only want it to remember, across every project, without your notes leaving the laptop by default. You care that deletion is predictable and auditable. And you'd rather judge a memory tool on a harness you can run yourself than on a comparison page — including this one.