Proton Mail MCP Server

An MCP server for Claude Code that provides email access through Proton Mail Bridge. Emails are synced to a local SQLite database with FTS5 full-text search for fast offline access.

Features

13 MCP tools: list, read, search, send, reply, move, mark, delete emails + attachment downloads
Local SQLite database: Sync email headers once, work offline. Bodies fetched lazily on demand
FTS5 full-text search: Search across subject, sender, recipient, and body — instant results across 13k+ emails
Incremental sync: First sync ~2-3 min, subsequent syncs in seconds
DB-first architecture: list_emails, read_email, search_emails serve from local DB when synced, IMAP fallback otherwise

Setup

Prerequisites

Python 3.10+
Proton Mail Bridge running locally
python-dotenv, mcp packages

1. Clone and configure

git clone https://github.com/DreamC0der-AI/proton-mail-mcp.git
cd proton-mail-mcp

Create a .env file with your Proton Bridge credentials:

EMAIL_USER=your@pm.me
EMAIL_PASS=your-bridge-password
IMAP_HOST=127.0.0.1
IMAP_PORT=1143
SMTP_HOST=127.0.0.1
SMTP_PORT=1025

2. Add to Claude Code

Copy example.mcp.json to your project's .mcp.json and update the path:

{
  "mcpServers": {
    "email": {
      "type": "stdio",
      "command": "python3",
      "args": ["/absolute/path/to/proton-mail-mcp/server.py"]
    }
  }
}

3. Sync emails

After restarting Claude Code, run sync_emails to pull headers into the local database. Then use local_search for instant full-text search.

Tools

| Tool | Description | |------|-------------| | sync_emails | Sync headers from IMAP to local DB (incremental) | | sync_status | Show sync state per mailbox | | local_search | FTS5 search: "exact phrase", word*, a AND b, a NOT b | | list_emails | List emails with filters (DB-first when synced) | | read_email | Read full email by UID (lazy body fetch + cache) | | search_emails | Search emails (FTS5 when synced, IMAP fallback) | | send_email | Send email via SMTP | | reply_email | Reply with proper threading headers | | mark_email | Mark as read/unread/flagged/unflagged | | move_email | Move between mailboxes | | delete_email | Move to Trash | | download_attachment | Download and track attachments | | list_downloads | List downloaded attachments | | list_mailboxes | List available mailboxes |

Architecture

server.py          MCP server (FastMCP, IMAP pool, SMTP, tool definitions)
db.py              EmailDB (SQLite + FTS5) + EmailSyncer (IMAP-to-DB sync)
.env               Credentials (gitignored)
data/              Local database + attachments (gitignored)
  emails.db        SQLite WAL database
  attachments/     Downloaded attachment files
tests/             Test suite

License

MIT

MCP Servers