Margins MCP Server

margins-mcp

Use your Claude Pro/Max subscription on your Obsidian vault. No API key. No per-token costs. No embedding pipelines. Claude reads your notes and proposes updates; your subscription pays for inference; your files stay on your disk.

margins-mcp is a small Node program that sits between Claude (Desktop or Code) and your Obsidian vault. When you chat with Claude, it reads your notes through margins-mcp. Your files stay local, Claude does the thinking, your existing subscription pays for it.

Which Margins are you?

Margins works for six common starting points. margins_start auto-detects your state on the first call, so you don't have to classify yourself — but knowing which row you're on helps set expectations.

Requirements

• Node.js 18 or newer
• An Obsidian vault, or any folder with notes, PDFs, Office/OpenDocument files, email exports, EPUBs, or plain text
• A Claude subscription: Pro ($20/mo), Max, or Claude Code

Install

Two commands:

npm install -g margins-mcp
margins-mcp install

The installer prompts for your vault path, detects Claude Desktop and Claude Code, writes the right config files, scaffolds raw/ + proposed/ + .margins/ inside your vault if missing, and runs a verification probe. Restart Claude Desktop (Cmd-Q on macOS, not just close the window), or in Claude Code run /mcp to see Margins listed.

Don't have a vault yet?

Scaffold a Margins-shaped one:

margins-mcp install --starter-vault ~/notes

Finding your Obsidian vault path

If you already use Obsidian and don't know your vault's absolute path:

• In Obsidian: right-click the vault name in the file tree → "Reveal in Finder" (macOS) or "Show in Explorer" (Windows). The path is in the title bar.
• macOS common paths: ~/Documents/<VaultName>, or ~/Library/CloudStorage/iCloudDrive/Obsidian/<VaultName> if iCloud-synced.
• Linux common paths: ~/Documents/<VaultName>, or ~/.local/share/Obsidian/<VaultName>.
• Windows common paths: %USERPROFILE%\Documents\<VaultName>.

Pass it to the installer via --vault /absolute/path or answer the prompt.

Try-without-installing

npx margins-mcp install --vault /path/to/vault

You'll see a warning that npm may garbage-collect the npx cache and your configs would break weeks later. For real use, prefer npm install -g above. The npx path is fine for kicking the tires.

Manual install

If you'd rather edit config yourself, add this to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS; see Anthropic docs for Windows/Linux paths):

{
  "mcpServers": {
    "margins": {
      "command": "node",
      "args": ["/absolute/path/to/margins-mcp/bin/margins-mcp.js"],
      "env": { "MARGINS_VAULT": "/absolute/path/to/your/vault" }
    }
  }
}

Try it

In a new Claude conversation, ask:

Use margins to give me a summary of my recent notes.

Or:

What pages support the claim that my project deadline is May 30th? Use margins to find them.

Or:

I just dropped a spreadsheet into raw/. Compile it into a structured source page in my wiki.

The model can read your vault, propose new pages, propose edits to existing ones, and pull raw sources into structured wiki pages. propose_compile_from_raw accepts Markdown/plain text, PDFs, Word docs, spreadsheets, decks, email exports, EPUBs, OpenDocument files, RTF, HTML, CSV/TSV, JSON, YAML, and common text-ish formats. Every write stages to proposed/ first; nothing lands without you accepting.

Tools

Context (call once per conversation)

Read

Propose writes (staged — nothing lands until accepted)

Suggest (for A3 / B3 — vaults with many files but few links)

Learn

How the proposal flow works

Every write tool stages to proposed/<path> inside your vault. Nothing touches the live tree until you (or an MCP client acting on your behalf) call resolve_proposal with action: "accept". You can also inspect staged content (ls proposed/) and accept by moving files yourself.

Sequential edits stack: a second propose_edit on the same path reads from the pending proposal, not the vault.

Configuration

What Margins is NOT

To keep scope crisp:

• Not an inference layer. Your Claude subscription pays for that. Margins makes zero LLM calls.
• Not a web app. The chat surface lives in Claude Desktop / Claude Code / claude.ai. Margins is plumbing.
• Not a cloud sync. Local-first. Your files stay on your disk.
• Not a CRM integration. Different product.
• Not API-key-based. Subscription-passthrough is the whole point.

Privacy

• Vault content never leaves your machine. Margins is a Node process that reads/writes files locally and exposes structured tools over stdio.
• Anonymous telemetry (opt-in at install time) reports tool-call counts to help me prioritize what to build next. Sample event payload: GET https://margins.goatcounter.com/count?p=/tool/search_vault. No vault content, no file paths, no user identifier beyond the standard 24-hour rolling session token GoatCounter assigns. Disable per-session with MARGINS_TELEMETRY=off. Decision stored at ~/.margins/consent.json.

Develop

git clone https://github.com/cflorczyk9/Margins.git
cd Margins
npm install
npm test
MARGINS_VAULT=/path/to/test/vault npm start

The compiler (src/compiler/) was originally vendored from an earlier Margins web app. The web app and its landing page live on the legacy-webapp branch in this repo. Re-vendor with scripts/vendor-compiler.sh if you ever need to pull updates back from there.

How Margins gets smarter over time

Two things compound:

1. Your vault's CLAUDE.md is auto-loaded by margins_start. Drop vault-specific rules in there — filing conventions, voice, naming patterns — and Claude obeys them in every conversation. No copy-paste.
2. .margins/preferences.md is a Margins-maintained file inside your vault. When you correct Claude ("no, that should be in projects, not personal"), Claude calls record_preference to remember the rule. Next conversation it reads them via recall_preferences before proposing writes. The file is plain Markdown — you can audit it, hand-edit it, delete sections that no longer apply.

Both files live in the vault, so they travel with it. Switch machines, switch hosts (Claude Desktop → Claude Code → ChatGPT once that lands), and your conventions follow.

Roadmap

• v0.6: web onboarding at marginsmcp.com — pick a folder via File System Access, scaffold a vault, get the install command. Closes B2/B3 personas without requiring CLI fluency.
• v0.6: get_citations (semantic embedding search, opt-in dep).
• v0.6: OCR/image, legacy Office binary, and audio/video ingestion for propose_compile_from_raw.
• v0.7: HTTP / Streamable transport for claude.ai web and ChatGPT custom connectors.
• v0.7+: Obsidian community plugin alongside MCP, if signal supports it.
• v0.8+: file watcher / auto-scaffold on drop into raw/.

License

MIT