Two official MCP servers, two different reaches
This is a closer comparison than most on this site. Joplin 3.7, released in August 2026, shipped a real MCP server built into the app, alongside semantic search and a set of AI tools. It is official, it is documented, and it is not a community plugin you have to keep alive yourself. On the axis most of these pages turn on, whether AI access is first-class, Joplin and Hjarni agree.
Where they part is the address. Joplin's MCP server rides on the existing Web Clipper service and listens on 127.0.0.1. Hjarni's is a hosted HTTPS endpoint that any MCP client authorizes over OAuth. Everything below follows from that one difference.
What localhost costs you
ChatGPT only accepts remote connectors, an HTTPS URL it can reach from OpenAI's servers. It has no way to reach into your laptop. So the official Joplin MCP server, as shipped, is not something you can add to ChatGPT. The same applies to Claude on the web, Claude on iOS and Android, and any assistant that is not a process running beside Joplin itself.
Even for desktop clients there is a shim. Stdio is not implemented in Joplin's first server version, and Claude Desktop speaks stdio, so the documented path is to point it through npx mcp-remote at the local port with the Web Clipper token. It works, and it is one more moving part that has to keep working.
And the server only answers while Joplin is open with Web Clipper started. Close the laptop and your AI's memory closes with it. Hjarni's notes are on a server, so an assistant reads them at 3am from a phone with no machine of yours involved.
Joplin gives your desktop AI your notes. Hjarni gives every AI your notes.
What Joplin does better
Two things, and they are not small. Joplin is open-source, so nothing about its future depends on a company staying solvent, and you can read the code that touches your notes. And it offers real end-to-end encryption: you can sync through Joplin Cloud, Dropbox, or S3 while holding keys the sync target does not have. Hjarni encrypts notes at rest in the EU, but Hjarni holds those keys. If your threat model includes the vendor, Joplin wins that argument outright and no amount of MCP convenience changes it.
Joplin's write-tool defaults are careful, too. Each tool is toggled individually and the write ones stay off until you turn them on. Their own documentation is blunt that Joplin will not ask you to confirm each write once they are enabled, which is a more honest warning than most apps give.
A concrete workflow difference
You are on a train, on your phone, and you want Claude to pull up what you decided about a supplier three months ago and add today's follow-up. With Joplin, the notes are on a laptop at home that is asleep, so there is nothing to ask. With Hjarni, Claude searches the folder, reads the note, and writes the follow-up back as a visible revision you can review later.
Flip it around. You are at your desk, you do not want anything leaving the machine, and you want an assistant that can read your journal without a vendor ever seeing it. That is Joplin's day, and Hjarni cannot offer it.
Can you host Joplin's MCP server yourself?
Partly. Because the endpoint is HTTP rather than stdio, people have put it behind a tunnel or rebuilt it as a hosted worker so remote clients can reach it, and the Data API has supported third-party servers for a while. If you enjoy running that, it is a legitimate answer and it gets you most of the reach.
It is worth being clear about what you are signing up for: a public endpoint in front of your notes, an auth story you own, and an uptime expectation, so that a chat on your phone works. Hjarni's position is not that this is impossible. It is that most people do not want a second job.
When Joplin is the better fit
Pick Joplin if open-source matters, if end-to-end encryption is a requirement rather than a preference, if you want to choose your own sync backend, or if your AI use is a desktop client on one machine. It is free, it is mature, it is genuinely good software, and its MCP server is the real thing. None of that is faint praise.
Migration and practical questions
Joplin exports as Markdown, with notebooks as folders. Hjarni's Markdown ZIP importer preserves folders, wiki-links, and frontmatter, so a Joplin export lands more or less intact. The real question is not the file format. It is whether you want your knowledge to live somewhere your assistants can always reach, or somewhere only you can.