An Obsidian vault is a folder of Markdown files, and Claude is very good at reading Markdown. So connecting the two sounds like a ten-minute job. On one computer, it mostly is. The trouble starts when you open Claude on your phone, or in the browser, and it has no idea your vault exists.
This article goes through the ways people connect Obsidian and Claude today, what each one needs, and where each one stops. Everything about third-party products was checked against their official pages on 13 October 2026.
Three ways to connect Obsidian and Claude
There isn't one "Obsidian MCP". MCP access to a vault comes from community plugins and general-purpose servers, and they fall into three groups.
The first needs no MCP at all. Claude Code works on the files in the folder you start it in, so if you start it inside your vault, it can read, search and edit your notes like any other text files. Nothing to install. Obsidian picks up the changes when you look at it.
The second is a plugin that runs inside Obsidian. The best known is Local REST API, a community plugin by Adam Coddington, now at version 5.4. It exposes the vault through a REST API protected by an API key and also serves MCP itself at /mcp/ over Streamable HTTP. By default it listens on https://127.0.0.1:27124, with a certificate signed by its own certificate authority, which it generates on first run. Its MCP tools can list, read, write, append to, patch, move and delete files, search the vault, list tags and run Obsidian commands. Other community servers, such as mcp-obsidian, are built on top of the same plugin.
The third treats the vault as a plain folder. The official Filesystem server from the MCP project gives an AI read and write access to the directories you allow, and nothing outside them. Point it at your vault and Obsidian doesn't even need to be open.
There's also a fourth road worth knowing about, though it isn't MCP. Obsidian 1.12 added an official command line interface, which you turn on under Settings → General. It needs the Obsidian app running (the first command starts it if it isn't), and an agent like Claude Code can call it from the shell like any other command.
What works
On a single desktop, all of this works well.
Claude Code talks to the plugin's MCP endpoint directly over HTTP. The usual snag is the certificate: your system doesn't trust the plugin's certificate authority until you tell it to, so you either trust it once or enable the optional plain HTTP server on port 27123. Or you skip MCP entirely and start Claude Code in the vault folder.
Claude Desktop can run local MCP servers configured in claude_desktop_config.json. That's how you add the Filesystem server, or mcp-obsidian. For the plugin's own endpoint, its documentation shows a bridge through mcp-remote. Cursor works too, and the plugin's page has setup examples for all three.
And when it works, it's useful. You ask Claude to find every note that mentions a client, summarise last month's meeting notes, or add a line to today's daily note, and it does it on your real files.
What doesn't work, and why
Everything above runs on your computer, and that's the limit.
Claude on the web, on your phone and in Cowork can't reach it. Anthropic's help center is explicit: Claude connects to remote MCP servers "from Anthropic's cloud infrastructure, rather than from your local device", on every client including Claude Desktop and the mobile apps. The server must be reachable over the public internet. Local servers in claude_desktop_config.json do use your local network, but Anthropic notes they aren't available in Cowork or claude.ai. A server on 127.0.0.1 is, by definition, not on the internet.
ChatGPT can't reach it directly either. OpenAI's products connect to remote MCP servers. For servers on a private network, OpenAI documents a tunnel: you run a small client next to the server, it opens an outbound connection to OpenAI, and requests travel back through it. That's an option for a developer. For most people with a vault it's one more moving part, and a path from the internet to their notes.
Nothing happens while the computer is off. The plugin lives inside Obsidian, so Obsidian has to be open. The Filesystem server doesn't need Obsidian, but it still needs the machine. If you're out with only your phone, your AI has no vault.
Phones and colleagues are out as well. Local REST API is a desktop-only plugin, and a colleague's AI can't reach your laptop. You wouldn't want to hand them the API key anyway.
Things to check before you let an AI write
Reading is harmless. Writing is where it gets interesting, because the AI is now editing the same notes you rely on.
First, know what the key opens. The plugin's MCP tools include writing, moving and deleting files across the vault. With the Filesystem server you can narrow access to specific folders, and that's a good habit: give the AI the project folder, not your journal.
Second, have a way back. Models make mistakes on writes, like replacing a long note with a short one. Before an agent starts editing, make sure you can restore yesterday's version, with git, a backup or whatever you already use.
Third, watch for two writers. If you edit a note in Obsidian while the AI edits the same file through the filesystem, the last save wins.
And don't put the plugin's port on the internet just to make the phone work. Doing that safely is exactly the job a tunnel or a hosted server exists for.
When an Obsidian MCP setup is enough
If you work alone, from one computer, with one AI that runs on that computer, a local setup is the right answer. Claude Code in the vault folder is the simplest version. The plugin is better if you want to use Obsidian's own search, tags and commands. You keep Obsidian's editor and plugins, and your notes never leave your disk.
It stops being enough when the questions change: when you want the same memory from the Claude app on your phone, from ChatGPT in the browser, from a coding agent on a server, or for a colleague who needs one folder and not the whole vault. All of those need the notes behind an address on the internet, with permissions.
Where Cobrain fits
Cobrain keeps the same kind of notes, Markdown files in folders with [[wikilinks]] and tags, behind a remote MCP address. Every AI you connect reaches the same brain, from any screen, and works with your permissions. You can bring your vault in as it is and export it again whenever you like. You can also keep Obsidian for writing and use Cobrain only for what your AIs and colleagues need to read. The Cobrain vs Obsidian page goes through the differences line by line, including when Obsidian alone is the better choice.
If you're comparing memory servers in general, what an MCP memory server is covers the questions that matter. To try it with Claude, the Claude guide takes a couple of minutes.
Quick answers
Can Claude read my Obsidian vault? Yes, on your computer. Claude Code can work directly in the vault folder, and Claude Desktop can use a local MCP server such as the Filesystem server or the Local REST API plugin.
Is there an official Obsidian MCP server?
Obsidian offers an official command line interface since version 1.12. MCP access comes from community plugins, such as Local REST API, which serves MCP at /mcp/, and from general servers like the MCP project's Filesystem server.
Why can't Claude on my phone see my vault? Because remote connectors connect from Anthropic's cloud, not from your device, so the server has to be reachable on the public internet. A plugin listening on your laptop isn't.
Does Obsidian need to be open for Claude to use the vault? For the plugin, yes: it runs inside Obsidian. Claude Code working on the folder, or the Filesystem server, only needs the files and the computer to be on.
