Proton Mail (unofficial)

io.github.sethbang/proton-mail-mcpv1.0.2Email

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

The current version, v1.0.2, was published to the official MCP registry on 2026-05-30. It is distributed as proton-mail-mcp on npm, filed under Email by this index, and declares 15 environment variables. Removals and unreachable sources are measured across every server this index tracks, contract drift across the servers that answer in consecutive snapshots; the index's current counts put this record in context.

In-path gate · all MCP tools

Using Proton Mail (unofficial) in Claude, Cursor, Gemini CLI, Cline, or Zed?

MCP tool contracts can change remotely with no version bump. The mcpindex gate pins each contract and HOLDs the call when it drifts-before your agent acts. Zero credentials. This is not the package install for this server itself (use Install this server for that).

Install the mcpindex gate (one command)

Rewrites your MCP host config so each server launches behind the gate. Inspect first: curl -fsSL https://mcpindex.ai/install.sh | less

uv tool install mcpindex-gate && mcpindex-config-wire

Auditable install path →Watch it hold a drift →

Trust verdict · v1 advisory · method

REVIEWstatus: PARTIALfresh until 2026-09-05 15:06 UTC

screened 2026-07-06tier: scannedgranularity: description-levelsource: registry

Semantic screen found no manipulation pattern in the description. Conformance probe not yet run.

mcpindex.integrity.descriptionpassINFO

evidence“Declared capabilities, no hidden instructions”via static_description

Limits of this verdict

- Semantic screen only - the deterministic conformance probe has not run on this server
- Confidence is reported but not yet calibrated (v1)
- Screen reads the tool description, not the live behavior
- advisory
- registry description only no input schema
- screen model 8b
- Still current: the description we screened is unchanged, re-checked against the registry

Semantic screen: an LLM judge reads the tool description for hidden instructions (status PARTIAL). A pass means the description is not lying, not that the tool is safe: a high-capability tool with an honest description still warrants caution. The deterministic conformance probe has not been run on this server yet, so the screen here is semantic-only. Posture: advisory. Confidences are reported but not yet calibrated (calibrated=false at v1). Full verdict history is not shown on this page.

Own this server? Screen its description →

That verdict was true at screening time (snapshot 2026-08-29).

Contracts can change after screening, with no version bump. The gate pins Proton Mail (unofficial)’s tool contracts on first sight and holds any silent change before your agent acts - the check that keeps being true on Tuesday.

See your first HOLD in 2 minutes →

Cite this record

People vet a server before wiring it in. One line on your project site or docs answers that with an independent record: screening verdict, registry provenance, contract drift history. It stays current as new screens and drift events land.

Markdown

[Independent trust record for Proton Mail (unofficial)](https://mcpindex.ai/server/io-github-sethbang-proton-mail-mcp) - screening verdict, registry provenance, and contract drift monitoring.

HTML

<a href="https://mcpindex.ai/server/io-github-sethbang-proton-mail-mcp">Independent trust record for Proton Mail (unofficial)</a> - screening verdict, registry provenance, and contract drift monitoring.

Embed this badge

A live verdict badge for your README or listing. It reflects the current screen, links back here, and updates when the verdict does.

Markdown

[![mcpindex](https://mcpindex.ai/api/v1/badge/io-github-sethbang-proton-mail-mcp)](https://mcpindex.ai/server/io-github-sethbang-proton-mail-mcp)

HTML

<a href="https://mcpindex.ai/server/io-github-sethbang-proton-mail-mcp"><img src="https://mcpindex.ai/api/v1/badge/io-github-sethbang-proton-mail-mcp" alt="mcpindex verdict" height="20" /></a>

Environment variables

PROTONMAIL_USERNAME

required

Your Proton Mail email address

PROTONMAIL_PASSWORD

requiredsecret

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

DEBUG

Enable verbose logging to stderr

MCP quality score · maturity, not trust · methodology

freshness

completeness

installability

documentation

stability

Alternatives in Email

Mermail

app.mermail/mcp

Privacy-first email inboxes for AI agents with MCP mail tools and Composio connect/execute.

MCP Emails

com.mcpemails/emails

Read, search, send, organize, draft and schedule email across your inboxes from any MCP client.

MCP fork of Google Workspace CLI

io.github.shigechika/gws-mcp

MCP fork of Google Workspace CLI (Gmail, Drive, Calendar, and more)

Install this server

Claude Desktop (claude_desktop_config.json)

{
  "mcpServers": {
    "proton-mail-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "--",
        "proton-mail-mcp"
      ],
      "env": {
        "PROTONMAIL_USERNAME": "<protonmail_username>",
        "PROTONMAIL_PASSWORD": "<your-protonmail_password>",
        "PROTONMAIL_HOST": "smtp.protonmail.ch",
        "PROTONMAIL_PORT": "587",
        "PROTONMAIL_SECURE": "false",
        "IMAP_HOST": "127.0.0.1",
        "IMAP_PORT": "1143",
        "IMAP_SECURE": "false",
        "IMAP_USERNAME": "<imap_username>",
        "IMAP_PASSWORD": "<your-imap_password>",
        "READONLY": "false",
        "RESTRICT_OUTBOUND_TO_SELF": "false",
        "ALLOW_FILE_DOWNLOAD_DIR": "<allow_file_download_dir>",
        "ALLOW_EMPTY_FOLDER": "false",
        "DEBUG": "false"
      }
    }
  }
}

Cursor (.cursor/mcp.json)

{
  "mcpServers": {
    "proton-mail-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "--",
        "proton-mail-mcp"
      ],
      "env": {
        "PROTONMAIL_USERNAME": "<protonmail_username>",
        "PROTONMAIL_PASSWORD": "<your-protonmail_password>",
        "PROTONMAIL_HOST": "smtp.protonmail.ch",
        "PROTONMAIL_PORT": "587",
        "PROTONMAIL_SECURE": "false",
        "IMAP_HOST": "127.0.0.1",
        "IMAP_PORT": "1143",
        "IMAP_SECURE": "false",
        "IMAP_USERNAME": "<imap_username>",
        "IMAP_PASSWORD": "<your-imap_password>",
        "READONLY": "false",
        "RESTRICT_OUTBOUND_TO_SELF": "false",
        "ALLOW_FILE_DOWNLOAD_DIR": "<allow_file_download_dir>",
        "ALLOW_EMPTY_FOLDER": "false",
        "DEBUG": "false"
      }
    }
  }
}

Cline (cline_mcp_settings.json)

npx -y -- proton-mail-mcp

Claude Code (claude mcp add)

claude mcp add --scope user proton-mail-mcp -- npx -y -- proton-mail-mcp

Gemini CLI (gemini mcp add)

gemini mcp add -s user proton-mail-mcp npx -y -- proton-mail-mcp

Verdict API

curl -s mcpindex.ai/api/v1/trust/server/io-github-sethbang-proton-mail-mcp

Free-tier verdict as JSON: decision + dimensions + severity. Call it from your agent before it invokes a tool it just discovered.

Details

version: v1.0.2
category: Email
verdict expires: 2026-09-05
quality: 90 / 100
operator: sethbang

Listing

Listed from the official MCP registry. Unclaimed by its maintainer. Maintainer? Email us →

Provenance

Each verdict is bound to a hash of the exact description it judged, so a re-crawl that changes the text produces a new record rather than silently inheriting this one. Verdict history is hash-chained and anchored to Bitcoin via OpenTimestamps (latest confirmed at block 964,530). Verify it yourself.

Links

Repository →Website →