io.github.karljsamuel/mcp-ecc

Official registry Productivity

Unified MCP server for Email, Calendar & Contacts (Google, M365, Zoho, IMAP/SMTP, DAV).

Install

Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).

NPM package mcp-ecc
Claude Code
claude mcp add mcp-ecc -e 'MCP_ENCRYPTION_KEY=<your mcp_encryption_key>' -- npx -y mcp-ecc@0.6.0
JSON configuration (Claude Desktop, Cursor, VS Code)
{
    "mcpServers": {
        "mcp-ecc": {
            "command": "npx",
            "args": [
                "-y",
                "mcp-ecc@0.6.0"
            ],
            "env": {
                "MCP_ENCRYPTION_KEY": "<your mcp_encryption_key>"
            }
        }
    }
}

Environment variables

  • MCP_ENCRYPTION_KEY required secret Master key used to encrypt stored credentials (AES-256-GCM). Generate with: openssl rand -hex 32

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. mcp-ecc
  2. Quick start
  3. Upgrade and encryption migration
  4. Connecting an MCP client
  5. Providers
  6. MCP tools
  7. Documentation
  8. Contributing
  9. Support & Contributions
  10. License

mcp-ecc

Email · Calendar · Contacts — one MCP server for all your accounts

A Model Context Protocol (MCP) server that lets AI assistants read, write and manage your email, calendar and contacts — across Google, Microsoft 365/Outlook, Zoho, and any IMAP/SMTP, CalDAV or CardDAV account — from a single interface.


mcp-ecc aggregates your mail, calendar and contacts into standardised MCP tools (mail.*, calendar.*, contacts.*, accounts.*) so any MCP client — Claude, Cursor, and others — can work with all of them uniformly.

  • One OAuth consent per cloud provider covers mail + calendar + contacts
  • Multi-user — users self-manage their own accounts, each with a per-user MCP API key
  • Credentials encrypted at rest (AES-256-GCM)
  • Self-hostable — single container serving a web admin UI, REST API and the MCP endpoint on one port

Quick start

Docker
docker run -d --name mcp-ecc \
  -p 3001:3001 \
  -e MCP_ENCRYPTION_KEY="$(openssl rand -hex 32)" \
  karljsamuel/mcp-ecc:latest

Open **http://localhost:3001** → create the admin account → add your provider accounts.

CLI (npm)
npm install -g mcp-ecc
mcp-ecc            # interactive TUI — login, add accounts, manage everything
mcp-ecc start      # stdio MCP server for agent hosts
From source
git clone https://github.com/karljsamuel/mcp-ecc.git
cd mcp-ecc
npm install
npm run build
node packages/cli/dist/bin.js --help

Upgrade and encryption migration

Important for existing installations: install and run the latest 0.6.x migration release before upgrading to 0.7.x.

The migration release changes credential encryption from the discontinued CryptoJS implementation to platform cryptography APIs:

  • Node.js SQLite uses node:crypto with authenticated AES-256-GCM.
  • Cloudflare D1 uses the Workers Web Crypto API with authenticated AES-256-GCM.
  • Existing 0.6.x ciphertext is read once and automatically re-encrypted in the new format.
  • New AES-256-GCM values are authenticated and migration is fail-closed.
  • Legacy CryptoJS ciphertext has no authentication tag; if it is tampered with, its integrity cannot be cryptographically verified. Back up the database and treat failed or unexpected legacy decryptions as migration failures; values are never overwritten unless decryption succeeds.
  • Keep the same MCP_ENCRYPTION_KEY during the upgrade.

After the migration release has successfully started and accessed the existing data, upgrade to 0.7.x. Version 0.7.x removes the legacy CryptoJS reader. Back up the SQLite database or D1 database before upgrading.

Connecting an MCP client

Point your client at the HTTP endpoint with your per-user API key (shown in the web UI under Settings):

{
  "mcpServers": {
    "mcp-ecc": {
      "type": "http",
      "url": "http://localhost:3001/mcp",
      "headers": { "Authorization": "Bearer <your-api-key>" }
    }
  }
}

Agents can read SKILL.md or llms.txt for guided, automated setup.


Providers

ProviderMailCalendarContactsAuthentication
Google (Gmail, Calendar, People)✅✅✅OAuth 2.0
Microsoft 365 / Outlook (Graph)✅✅✅OAuth 2.0
Zoho (Mail, Calendar, Contacts)✅✅✅OAuth 2.0
IMAP / SMTP (any mail server)✅❌❌App password
CalDAV (Nextcloud, Radicale, BAIKAL)❌✅❌Password
CardDAV❌❌✅Password

Microsoft 365: app passwords are being retired — use OAuth (Microsoft Graph) only.

CalDAV/CardDAV compatibility: the providers implement standard WebDAV (CalDAV RFC 4791, CardDAV RFC 6352) with Basic auth and should work with any standards-compliant server. Tested against Radicale 3.7.8. Not tested against other servers; OAuth-only providers (e.g. iCloud without an app-specific password) are not supported.

Deployment notes: Google/Microsoft/Zoho/IMAP/SMTP/CalDAV/CardDAV run under Node.js (CLI or Docker). Cloudflare D1 can be used as a hosted alternative for the local SQLite database.


MCP tools

mail.listFolders · mail.listMessages · mail.getMessage · mail.sendMessage
mail.searchMessages · mail.moveMessage · mail.setFlags · mail.deleteMessage

calendar.listCalendars · calendar.listEvents · calendar.getEvent · calendar.freeBusy
calendar.createEvent · calendar.updateEvent · calendar.deleteEvent

contacts.list · contacts.get · contacts.create · contacts.update
contacts.delete · contacts.search

accounts.list · accounts.get · accounts.add · accounts.remove · accounts.sync

Full reference with input schemas: docs/mcp-tools.md


Documentation


Contributing

Feature branches off dev; PRs against dev. Run npm run build to compile all packages. Keep Changelog.md and docs/ in sync.

Support & Contributions

If you find mcp-ecc useful, consider supporting its development:


License

Frequently asked questions

What is io.github.karljsamuel/mcp-ecc?

Unified MCP server for Email, Calendar & Contacts (Google, M365, Zoho, IMAP/SMTP, DAV).

How do I install io.github.karljsamuel/mcp-ecc?

It runs on your machine. In Claude Code: claude mcp add mcp-ecc -e 'MCP_ENCRYPTION_KEY=<your mcp_encryption_key>' -- npx -y mcp-ecc@0.6.0. For other clients, paste the JSON configuration from this page into their MCP settings.

Does io.github.karljsamuel/mcp-ecc need an API key?

Yes. It expects MCP_ENCRYPTION_KEY, which you set in its configuration.

Is io.github.karljsamuel/mcp-ecc open source?

Yes. Its code is on GitHub under the MIT license.

Who maintains io.github.karljsamuel/mcp-ecc?

It is published by karljsamuel. AI.tn lists it but does not maintain or endorse it.

From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.