mnemoverse/mcp-memory-server

**Persistent memory for AI agents over MCP.** Tell it a recalled memory helped or misled, and it re-ranks what comes back next. Shared rooms let several agents work from one memory. One key or OAuth across Claude Code, Cursor, VS Code and ChatGPT.
@mnemoverse/mcp-memory-server is the MIT-licensed MCP server for the hosted Mnemoverse memory engine.
What is Mnemoverse Memory?
Mnemoverse is a hosted memory engine for AI agents, reached over the Model Context Protocol. Mnemoverse stores what your agents learn — decisions, preferences, lessons — and returns it in any connected tool, so one memory follows you across Claude Code, Cursor, VS Code and ChatGPT with one account: an API key in a local config, or an OAuth sign-in on the hosted endpoint. Mnemoverse re-ranks recall from outcomes: report that a recalled memory helped and a Rescorla-Wagner update on the prediction error raises it, report that it misled and it sinks — a different mechanism from similarity scoring, usable alongside it.
**What is open source here, and what is not.** This repository, the MCP server, is MIT, and so is the Python SDK. The memory engine they talk to is a hosted service with a free tier. Self-hosting the engine is available on Enterprise plans by agreement, when security or compliance requirements call for it; by default we run it for you.
How it compares
Most agent memory today lives in one of three places. Per-tool instruction files — CLAUDE.md, .cursorrules, AGENTS.md — are versioned and readable, but each copy belongs to one repo and one tool, and nothing follows you to the next window. A vector store behind RAG retrieves by similarity, and similarity never changes because advice helped or misled. Local-first memory servers win on privacy and latency, and ask you to run and update the infrastructure yourself. Mnemoverse is the managed, cross-tool option in that landscape: nothing to deploy, one account everywhere, and ranking that moves with reported outcomes. If you need memory inside your own perimeter, a local-first server is the better choice; this one is hosted by default, with Enterprise self-hosting by agreement.
The consolidation stage of the engine — HDBSCAN clustering with Von Restorff protection, so distinctive memories are not absorbed into the average — is designed in and currently switched off on the hosted service; our docs say so rather than hide it.
> ⭐ If Mnemoverse saves you from re-explaining context to your agents, star the repo. It helps other builders find it.
Quick Start
No key: the hosted endpoint
If your client signs in over OAuth, you do not need a key at all. Create a free account at console.mnemoverse.com (no credit card), then connect the hosted endpoint.
Claude Code:
Then run /mcp in a session, select mnemoverse and choose **Authenticate**.
Cursor, in .cursor/mcp.json:
Claude Desktop, Devin Desktop (formerly Windsurf), VS Code and ChatGPT: Remote MCP setup. The local server below is the other path: it runs on your machine and reads an API key.
1. Get a free API key
Sign up at console.mnemoverse.com — takes 30 seconds, no credit card.
**Check the key before you put it in a config.** Both forms ask for the key at a masked prompt and never pass it as a command argument, so it lands neither in your shell history nor in the process list.
macOS, Linux, Git Bash:
Windows PowerShell 5.1 and PowerShell 7:
| The output contains | What it means |
|---|---|
| JSON that includes "total_atoms" | The key works. |
| "reason":"placeholder_key" | That is the example key from these docs. Create a real one at the console. |
| "reason":"malformed_key" | Not the shape of a key: cut short in the paste, wrapped in quotes, or a different token entirely. |
| "reason":"invalid_key" | The shape is right and no such key exists. Copy it again from the console. |
| "reason":"revoked_key" | The key was revoked and will not work again. Create a new one. |
| "reason":"missing_key" | No key reached the API: what you entered was empty. |
In the JSON, reason sits inside the details object (details.reason), next to details.keys_url, the console page where keys are created.
2. Connect to your AI tool
The two canonical setups, Claude Code and Cursor. Cursor's button adds the hosted server with a browser sign-in and no key; every setup that takes a key writes it **once, at user scope, covering every project**. Avoid a per-project config file for a key: it lives inside the repository and can be committed with it, and a key belongs outside: