MemOS
Universal, local-first, persistent memory layer for AI agents. Give any LLM a memory that survives restarts — no cloud, no API keys, no vendor lock-in, and no subscription.
Quick start
Key features
- 100% local SQLite-backed storage (no cloud)
- Graph-native with typed edges
- Temporal validity (validFrom/validTo)
- Trust scoring & provenance tracking
- Confidence score state machine
- Compact TOON context packs
- MCP adapter (stdio + Streamable HTTP, 2026-07-28)
- 40 MCP tools · session-start overview · task triggers
- Review queue for inferred memories
- Source-scoped deletion with proof-of-forgetting
- Framework-agnostic (Ollama, LangChain, CrewAI)
Benchmarks — long-horizon recall
Same-protocol run: 304 LoCoMo questions, 2 conversations, identical embedder (nomic-embed-text), no reranker on either side. Overall Hit@10 was a 65.6%–65.6% tie; MemOS leads on adversarial memories by 16.9 points, where trust and provenance filtering matter. One slice, so treat it as a signal with caveats.
| Benchmark | MemOS | Protocol |
|---|---|---|
| LongMemEval-S · Hit@20 | 99.4% | 500 questions · nomic 768d · saturated |
| LoCoMo · Hit@10 | 65.0% | 1,986 questions · bge-small · repeatable |
| ConvoMem · Hit@10 | 91.0% | 387 questions · all-MiniLM |
| LoCoMo same-protocol · Hit@10 | 65.6% | 304 questions · vs Mem0 65.6% |
| End-to-end QA | 78.0% | 50 questions · independent GLM judge |
Every row traces to a committed artifact or a documented run. LongMemEval retrieval is saturated at k=20 (BM25 reaches 99.6%), so we do not treat it as a differentiator. The honest comparison is the same-protocol LoCoMo slice, where the systems tie overall and separate on adversarial cases. See the methodology.
Free and open source — actually
MemOS is MIT-licensed and completely free — to use, to modify, to self-host, to ship in your product. There is no hosted platform, no usage metering, and no paid tier hiding the good features. Mem0's platform, by contrast, starts at $19/month and charges $249/month for graph memory — the kind of feature MemOS includes by default.
| MemOS | Mem0 platform | |
|---|---|---|
| Price | Free. Forever. | Free tier capped · $19–$249/mo after |
| Source code | 100% open source (MIT) | Open core — platform is proprietary |
| Your data | SQLite file on your disk | Hosted in their cloud |
| API keys / account | None required | Account + API key required |
| Modify & self-host | Fork it, change it, ship it | Not available on the platform |
| Graph memory | Included, free | Pro plan ($249/mo) only |
Mem0 pricing as published on mem0.ai/pricing (Hobby free with request caps, Starter $19/mo, Pro $249/mo, Enterprise custom). Mem0's open-source library exists too — but the platform most people use is the paid one, and your memories live in their cloud.