Pyfastmail

FreeNot checked

An MCP server that provides AI assistants with full access to Fastmail accounts for managing email, contacts, calendars, and file storage. It implements 42 tool

by pjosols

GitHub Embed

About

An MCP server that provides AI assistants with full access to Fastmail accounts for managing email, contacts, calendars, and file storage. It implements 42 tools across JMAP, CardDAV, CalDAV, and WebDAV protocols to enable comprehensive account interaction through natural language.

README

An MCP server that gives AI assistants full access to your Fastmail account — email, contacts, calendars, and file storage.

⚠️ This server can send email, delete messages, and modify contacts/calendars on your behalf. AI assistants may act on content from untrusted sources (emails, web pages, files) which could contain prompt injection attacks. Review tool calls before approving them, especially actions that send email or delete data.

Features

Domain	Protocol	Tools
Mail	JMAP	Send, reply, forward, search, read, pin, archive, keywords, masked email, attachments, threads, import/export, identities
Contacts	JMAP	List address books, CRUD contacts, query
Calendar	CalDAV	List calendars, CRUD events (optional — requires app password)
Files	WebDAV	List, upload, download, move, delete, create folders (optional — requires app password)

Installation

pip install pyfastmail-mcp

Or run directly with uvx:

uvx pyfastmail-mcp

Configuration

1. Get Fastmail Credentials

You need an API token from Fastmail. An app password is optional (only needed for calendar and file storage).

API Token (required — mail and contacts): Fastmail Settings → Privacy & Security → API Tokens — enable the urn:ietf:params:jmap:contacts capability
App Password (optional — calendars and files): Fastmail Settings → Privacy & Security → App Passwords — create one with the "DAV (CardDAV, CalDAV, WebDAV)" scope

If you only set the API token, the server starts with mail and contacts tools. Calendar and file tools are registered only when the app password is also provided.

2. Set Environment Variables

export FASTMAIL_API_TOKEN="fmu1-..."
export FASTMAIL_APP_PASSWORD="your-app-password"
export FASTMAIL_EMAIL="[email protected]"

3. Add to Your MCP Client

For Claude Desktop, add to claude_desktop_config.json:

{
  "mcpServers": {
    "fastmail": {
      "command": "uvx",
      "args": ["pyfastmail-mcp"],
      "env": {
        "FASTMAIL_API_TOKEN": "fmu1-...",
        "FASTMAIL_APP_PASSWORD": "your-app-password",
        "FASTMAIL_EMAIL": "[email protected]"
      }
    }
  }
}

For Kiro CLI, add to .kiro/settings/mcp.json:

{
  "mcpServers": {
    "fastmail": {
      "command": "uvx",
      "args": ["pyfastmail-mcp"],
      "env": {
        "FASTMAIL_API_TOKEN": "${FASTMAIL_API_TOKEN}",
        "FASTMAIL_EMAIL": "${FASTMAIL_EMAIL}",
        "FASTMAIL_APP_PASSWORD": "${FASTMAIL_APP_PASSWORD}"
      }
    }
  }
}

Tools

Mail (`mail_*`)

Tool	Description
`health_check`	Verify connection and auth
`mail_list_mailboxes`	List all mailboxes (folders/labels)
`mail_create_mailbox`	Create a mailbox
`mail_rename_mailbox`	Rename a mailbox
`mail_delete_mailbox`	Delete a mailbox
`mail_get_email`	Get email by ID (with optional headers)
`mail_get_recent_emails`	Get recent emails
`mail_search_emails`	Search by query
`mail_search_snippets`	Highlighted search result snippets
`mail_get_email_thread`	Get full thread
`mail_mark_email_read`	Mark read/unread
`mail_pin_email`	Pin/unpin (flag/star)
`mail_move_email`	Move to mailbox
`mail_delete_email`	Move to trash or permanently delete
`mail_archive_email`	Archive
`mail_manage_email_labels`	Add/remove keywords
`mail_export_email`	Download raw .eml file
`mail_import_email`	Import .eml into mail store
`mail_parse_email`	Parse a blob as email without importing
`mail_list_identities`	List send-as identities
`mail_set_identity`	Create/update/delete identities
`mail_send_email`	Send new email
`mail_reply_to_email`	Reply to email
`mail_forward_email`	Forward email
`mail_list_masked_emails`	List masked emails
`mail_create_masked_email`	Create masked email
`mail_update_masked_email`	Update masked email state, domain, description, or URL
`mail_download_attachment`	Download attachment
`mail_upload_attachment`	Upload blob for sending

Contacts (`contacts_*`)

Tool	Description
`contacts_list_address_books`	List address books
`contacts_list`	List contacts (query+get combo)
`contacts_get_contact`	Get contact(s) by ID
`contacts_query_contacts`	Query contacts with filters and sorting
`contacts_create_contact`	Create contact
`contacts_update_contact`	Update contact fields
`contacts_delete_contact`	Delete contact(s)

Calendar (`calendar_*`)

Tool	Description
`calendar_list_calendars`	List calendars
`calendar_list_events`	List events
`calendar_get_event`	Get event details
`calendar_create_event`	Create event
`calendar_update_event`	Update event
`calendar_delete_event`	Delete event

Files (`files_*`)

Tool	Description
`files_list`	List files/folders
`files_get`	Download file
`files_upload`	Upload file
`files_create_folder`	Create folder
`files_move`	Move/rename file
`files_delete`	Delete file/folder

Development

git clone https://github.com/pjosols/pyfastmail-mcp.git
cd pyfastmail-mcp
uv sync --group dev
uv run pytest

License

MIT

from github.com/pjosols/pyfastmail-mcp

Install Pyfastmail in Claude Desktop, Claude Code & Cursor

Recommended · one command, every IDE

unyly install pyfastmail-mcp

Installs into Claude Desktop, Claude Code, Cursor & VS Code — handles npx, uvx and build-from-source repos for you.

First time? Get the CLI: curl -fsSL https://unyly.org/install | sh

Or configure manually

Run in your terminal:

claude mcp add pyfastmail-mcp -- uvx pyfastmail-mcp

Step-by-step: how to install Pyfastmail

Install Pyfastmail in Claude Desktop Install Pyfastmail in Claude Code Install Pyfastmail in Cursor Install Pyfastmail in VS Code

FAQ

Is Pyfastmail MCP free?

Yes, Pyfastmail MCP is free — one-click install via Unyly at no cost.

Does Pyfastmail need an API key?

No, Pyfastmail runs without API keys or environment variables.

Is Pyfastmail hosted or self-hosted?

A hosted option is available: Unyly runs the server in the cloud, no local setup required.

How do I install Pyfastmail in Claude Desktop, Claude Code or Cursor?

Open Pyfastmail on unyly.org, pick your client tab (Claude Desktop, Claude Code, Cursor) and press Install — the config is generated automatically, no JSON editing.

Related MCPs

Gmail

Read, send and search emails from Claude

by Google

Slack

Send, search and summarize Slack messages

by Slack

Runbear

No-code MCP client for team chat platforms, such as Slack, Microsoft Teams, and Discord.

by Community

Discord Server

A community discord server dedicated to MCP by [Frank Fiegel](https://github.com/punkpeye)

by Community

Compare Pyfastmail with

PyfastmailvsGmail PyfastmailvsSlack PyfastmailvsRunbear PyfastmailvsDiscord Server

Not sure what to pick?

Find your stack in 60 seconds

Author?

Embed badge for your README

Browse similar

All communication MCPs