claude-mail-mcp

Self-hosted IMAP / SMTP / CalDAV connector for Claude with multi-account support. A Streamable HTTP MCP server that lets Claude.ai read and write your email + calendar against any RFC-compliant mailbox.

Built because every other Claude email connector targets Gmail. This one is for the rest of us — Mailbox.org, Fastmail, iCloud, Mailcow, iRedMail, Migadu, Nextcloud, your own Postfix box. If your provider speaks IMAP, SMTP and CalDAV, this works. One connector, all your inboxes.

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What it does

Exposes 14 MCP tools to Claude:

Accounts (1)

Mail (9)

Calendar (4)

Every tool accepts an optional account: "" parameter to pick a mailbox; omit it to use the default account. So “list unread in INBOX of work account” vs “compare today’s calendar across work and personal” both work in one connector.

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Why bring-your-own-server?

Hosted email-AI services need full mailbox access. That’s a lot of trust to hand to a vendor. This connector flips the model: you run it, you hold the credentials, no third party between Claude and your inbox.

• One Node process per mailbox
• Credentials in a single .env file
• One Bearer token gates every MCP call
• Add the URL to Claude.ai once, done

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Quick start

git clone https://github.com/maxx3250/claude-mail-mcp.git
cd claude-mail-mcp
npm install
cp .env.example .env
# Generate an AUTH_TOKEN and fill it into .env:
#   echo "AUTH_TOKEN=$(openssl rand -hex 32)" >> .env
npm run build
npm start

The server boots with no mailboxes configured — that’s fine. Add them via the OAuth shim’s /settings UI (see Deployment) or hand-craft an accounts.json:

{
  "version": 1,
  "accounts": [
    {
      "id": "main",