What happens when you run Obsidian on a headless Linux server, sync it across every device, and wire Claude into the whole thing via MCP (Model Context Protocol, Anthropic's standard for connecting AI models to external tools)?
Developer Daniel McCarthy built exactly this, and the result is closer to a real personal assistant than most AI setups people share online. The core idea: Obsidian isn't just a note-taking app on his laptop. It's a synchronized knowledge base running 24/7 on a Hetzner server, accessible to Claude through an MCP server called obsidian-web-mcp.
The vault follows a five-folder structure: Polaris (goals and priorities), Logs (daily and weekly notes), Commonplace (personal knowledge), Outputs (AI-generated content and meeting transcripts), and Utilities (templates). That last distinction matters. AI-generated content gets its own folder so it doesn't pollute the human-curated knowledge graph.
Claude connects to more than just the notes. The setup pulls in Linear for task management, Granola for meeting transcriptions, a work calendar, and Slack. Every morning, an automated macOS task triggers Claude to check calendar changes, process quick captures from the phone, populate daily notes with current Linear issues, and flag unreplied Slack messages.
The technical stack is straightforward: Obsidian Sync keeps everything in lockstep across devices, Tailscale provides secure remote access to the MCP server, and a CLAUDE.md file gives Claude its instructions and context about the vault structure.
McCarthy is upfront that none of this is technically novel. Each piece already existed. The value is in connecting them with clear enough instructions that Claude can actually navigate a personal knowledge base without constant hand-holding. That's the hard part most people skip: structuring your notes so an AI can reliably find and use them.
This kind of setup requires comfort with self-hosting and some patience with MCP configuration, but it's a solid blueprint for anyone who already lives in Obsidian and wants Claude to do more than answer one-off questions.