Proton Mail Bridge Client

  ____  ____   ___ _____ ___  _   _   __  __    _    ___ _
 |  _ \|  _ \ / _ \_   _/ _ \| \ | | |  \/  |  / \  |_ _| |
 | |_) | |_) | | | || || | | |  \| | | |\/| | / _ \  | || |
 |  __/|  _ <| |_| || || |_| | |\  | | |  | |/ ___ \ | || |___
 |_|   |_| \_\\___/ |_| \___/|_| \_| |_|  |_/_/   \_\___|_____|
  Bridge Client  ·  CLI + Claude Desktop MCP for Proton Mail

---

Give Claude Desktop (or Cline, or any MCP client) full access to your Proton Mail inbox: read, search, send, draft, triage threads, manage folders, save attachments, and more — 100 MCP tools in total. Most of the same capabilities are also available as a full CLI for scripting, cron, and piped automation — no Claude required.

Using Proton Drive too? See proton-drive-mcp, the companion MCP server and CLI for Proton Drive (upload, download, share and manage your encrypted files from Claude). Run both side by side to handle mail and files in one conversation, for example save an attachment from here, then upload it to Drive. More in Related projects.

Battle-tested at scale (v2.0.0): full mailbox backfill validated end-to-end against a real account with 57,000+ indexed messages across 62 folders/labels — including a 22,800-message Archive folder backfilled from scratch, UID-window by UID-window, with zero data loss across restarts, transient IMAP disconnects, and connection timeouts.

Quick start (2 minutes)

No terminal? Follow the step-by-step guide instead.

1. Install and sign in to Proton Mail Bridge, and leave it running. In the Bridge app, open your account and copy the Bridge password (it is not your Proton password).
2. Connect Claude Desktop, either way:
   • Bundle: download the proton-mail-bridge-client-<your-os>.mcpb for macOS (darwin-arm64 Apple silicon, darwin-x64 Intel), Linux (linux-x64, linux-arm64) or Windows (win32-x64) from the latest release and open it. Claude Desktop asks for your Proton address and the Bridge password, plus optional settings (Bridge IMAP/SMTP host and port, read-only, allow sending, signature, extra accounts, data and download folders, tool tier); the defaults match a standard Bridge install.
   • npm: npm install -g proton-mail-bridge-client, then proton-mail-bridge-client setup-claude-desktop (it checks your Bridge ports and writes the config). Fully quit and reopen Claude Desktop afterwards.
3. Check it works: run proton-mail-bridge-client doctor, or ask Claude "run the Proton Mail doctor".
4. Try these prompts:
   • "Give me a digest of my inbox and flag anything that needs a reply today."
   • "Find the last email from alice@example.com and draft a reply for me to review." (nothing is sent until you say so)
   • "Which of my emails have attachments from this month?"
   • "Show me my drafts and tighten the oldest one."
5. Optional: PROTONMAIL_READ_ONLY=true to browse without being able to change anything, PROTONMAIL_TOOL_TIER=core for a smaller tool set (25 instead of 100), and more accounts under Multi-account support. More recipes below in Try it.

---

What you get