Proton Mail (unofficial) MCP Server

What this does

Proton Mail (unofficial) exposes a set of tools to Claude over the Model Context Protocol. After you add it to claude_desktop_config.json (snippet above) and restart Claude Desktop, those tools become callable inside any conversation.

Requirements

This server needs the following environment variables to be set before it can run:

PROTONMAIL_USERNAME
PROTONMAIL_PASSWORD
PROTONMAIL_HOST
PROTONMAIL_PORT
PROTONMAIL_SECURE
IMAP_HOST
IMAP_PORT
IMAP_SECURE
IMAP_USERNAME
IMAP_PASSWORD
READONLY
RESTRICT_OUTBOUND_TO_SELF
ALLOW_FILE_DOWNLOAD_DIR
ALLOW_EMPTY_FOLDER
DEBUG

Set these via the env object in your MCP config (see claude_desktop_config.json snippet above).

How do I install Proton Mail (unofficial)?

Run the Claude Code command in the install section to add Proton Mail (unofficial) to Claude Code, or copy the ready-made config for your client from the install section on this page. Restart your client afterwards and the tools appear in your next conversation.

Which clients work with Proton Mail (unofficial)?

This page carries setup and config for Claude Code, Claude Desktop, Cursor and VS Code. Any other MCP client that accepts a standard server config can connect to Proton Mail (unofficial) as well.

Does Proton Mail (unofficial) need an API key?

Yes. Before it can run, set these environment variables: PROTONMAIL_USERNAME, PROTONMAIL_PASSWORD, PROTONMAIL_HOST, PROTONMAIL_PORT, PROTONMAIL_SECURE, IMAP_HOST, IMAP_PORT, IMAP_SECURE, IMAP_USERNAME, IMAP_PASSWORD, READONLY, RESTRICT_OUTBOUND_TO_SELF, ALLOW_FILE_DOWNLOAD_DIR, ALLOW_EMPTY_FOLDER, DEBUG. They go in the env block of your MCP config.