Proton Mail (unofficial) MCP Server

io.github.sethbang/proton-mail-mcp

Repository Registry

What is the Proton Mail (unofficial) MCP server?

Unofficial Proton Mail MCP — send, read, search & organize email over SMTP and IMAP

How to install Proton Mail (unofficial)

Copy-paste configuration for popular MCP clients.

transport: stdio

Config generated by PluginBench — verify against the source before use.

Environment / auth

PROTONMAIL_USERNAME
required
Your Proton Mail email address
PROTONMAIL_PASSWORD
required
secret
Your Proton Mail SMTP password (not your login password; generate one in Proton settings)
PROTONMAIL_HOST
SMTP host
PROTONMAIL_PORT
SMTP port
PROTONMAIL_SECURE
Use TLS for SMTP (true for port 465)
IMAP_HOST
Proton Mail Bridge IMAP host (required for read/search tools)
IMAP_PORT
Proton Mail Bridge IMAP port
IMAP_SECURE
Use TLS for IMAP
IMAP_USERNAME
Proton Mail Bridge username (falls back to PROTONMAIL_USERNAME)
IMAP_PASSWORD
secret
Proton Mail Bridge password (falls back to PROTONMAIL_PASSWORD)
READONLY
Disable all mutating tools (send, move, delete, flags, labels, bulk ops, folder/label management)
RESTRICT_OUTBOUND_TO_SELF
Refuse live sends to any recipient other than PROTONMAIL_USERNAME (for throwaway/QA accounts)
ALLOW_FILE_DOWNLOAD_DIR
Allowlist directory enabling download_attachment.saveTo; when unset, attachments return as inline base64
ALLOW_EMPTY_FOLDER
Register the empty_folder tool (not recommended)
DEBUG
Enable verbose logging to stderr

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "proton-mail-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "proton-mail-mcp"
      ],
      "env": {
        "PROTONMAIL_USERNAME": "<YOUR_PROTONMAIL_USERNAME>",
        "PROTONMAIL_PASSWORD": "<YOUR_PROTONMAIL_PASSWORD>",
        "PROTONMAIL_HOST": "<YOUR_PROTONMAIL_HOST>",
        "PROTONMAIL_PORT": "<YOUR_PROTONMAIL_PORT>",
        "PROTONMAIL_SECURE": "<YOUR_PROTONMAIL_SECURE>",
        "IMAP_HOST": "<YOUR_IMAP_HOST>",
        "IMAP_PORT": "<YOUR_IMAP_PORT>",
        "IMAP_SECURE": "<YOUR_IMAP_SECURE>",
        "IMAP_USERNAME": "<YOUR_IMAP_USERNAME>",
        "IMAP_PASSWORD": "<YOUR_IMAP_PASSWORD>",
        "READONLY": "<YOUR_READONLY>",
        "RESTRICT_OUTBOUND_TO_SELF": "<YOUR_RESTRICT_OUTBOUND_TO_SELF>",
        "ALLOW_FILE_DOWNLOAD_DIR": "<YOUR_ALLOW_FILE_DOWNLOAD_DIR>",
        "ALLOW_EMPTY_FOLDER": "<YOUR_ALLOW_EMPTY_FOLDER>",
        "DEBUG": "<YOUR_DEBUG>"
      }
    }
  }
}