Practical overview
When it fits
Use Mnemosyne when an agent needs persistent, traceable memory and its downstream guidance should respond to corrections. Choose the Local Engine for a self-contained SQLite store, or the Vector Engine when the application uses its service-backed architecture.
Who it is for
- Developers building AI agents that need memory across sessions.
- Teams that need to track source evidence and retire dependent guidance after corrections.
- Developers connecting agent memory through TypeScript, Model Context Protocol, CLI or authenticated HTTP.
Documented uses
- Store agent facts and procedures with source details, visibility and trust labels.
- Compile relevant memory into context for an agent while exposing citations and uncertainty.
- Correct a record and invalidate dependent procedures that are no longer current.
- Hand off goals, decisions and next steps between agents.
- Connect an existing memory store through a read-only bridge for gradual migration.
Requirements & limits
The repository identifies an MIT license. Version 2.0.0-rc.9 is a release candidate; the README says stable npm latest remains on 1.x and the 2.0 candidate is available through the next channel.
- The Local and Vector Engines have separate schemas and do not automatically synchronize or migrate data.
- The Vector Engine requires configured external services; the Local Engine uses SQLite and does not require a model API key, database server or Docker.
- Dependencies must be declared by the controller for corrections to invalidate dependent procedures.
- The observed trust label records that the host recorded a source; it does not certify the source as true.
- The default context counter measures UTF-8 bytes conservatively, not a model tokenizer.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Run the Local Engine demonstration
Install the version 2.0.0-rc.9 candidate and run its documented demos.
Before you start
- Node.js 22.16 or later; Node 24 is recommended.
- An npm project environment.
Steps
Install the exact candidate with the command below.
npm install mnemosy-ai@2.0.0-rc.9Run the command below.
npx --no-install mnemosy demoRun the command below.
npx --no-install mnemosy learning-demo
Expected outcome
The first demo shows a handoff, correction, private scope and forgetting; the learning demo exercises capture, scripted observation, skill trials, sharing and correction-driven retirement. The README says these use local APIs and deterministic fixtures without model calls.
Guide limitations
- This is a release candidate; the README recommends evaluating it on your own workload before production.
- Unqualified
npm install mnemosy-aiselects the stable 1.x channel, not this candidate.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 8 October 2026
- Original website title
- 28naem-del/mnemosyne · Official homepage title · retained in its source language

