JXA Mail MCP

A fast MCP (Model Context Protocol) server for Apple Mail, using optimized JXA (JavaScript for Automation) scripts with batch property fetching for 87x faster performance.

Features

• list_accounts - List all configured email accounts
• list_mailboxes - List mailboxes for an account
• get_emails - Fetch emails from any mailbox with pagination
• get_todays_emails - Fetch all emails received today
• get_unread_emails - Fetch unread emails
• get_flagged_emails - Fetch flagged emails
• search_emails - Search emails by subject or sender
• fuzzy_search_emails - Typo-tolerant search using trigram + Levenshtein matching

Installation

With pipx (recommended)

pipx install jxa-mail-mcp

From source

Requires Python 3.13+ and uv:

git clone https://github.com/imdinu/jxa-mail-mcp
cd jxa-mail-mcp
uv sync

Usage

Add to Claude Code

After installing with pipx:

{
  "mcpServers": {
    "mail": {
      "command": "jxa-mail-mcp"
    }
  }
}

Or from source:

{
  "mcpServers": {
    "mail": {
      "command": "uv",
      "args": ["run", "--directory", "/path/to/jxa-mail-mcp", "jxa-mail-mcp"]
    }
  }
}

Run directly

jxa-mail-mcp

Configuration

Set default account and mailbox via environment variables:

export JXA_MAIL_DEFAULT_ACCOUNT="Work"
export JXA_MAIL_DEFAULT_MAILBOX="Inbox"

Or in Claude Code config:

{
  "mcpServers": {
    "mail": {
      "command": "jxa-mail-mcp",
      "env": {
        "JXA_MAIL_DEFAULT_ACCOUNT": "Work"
      }
    }
  }
}

Test in Python

from jxa_mail_mcp.server import get_todays_emails, search_emails, fuzzy_search_emails

emails = get_todays_emails(account="iCloud", mailbox="Inbox")
results = search_emails("meeting", account="Work", limit=10)

# Fuzzy search - tolerates typos
results = fuzzy_search_emails("meetting nottes", limit=10)  # finds "meeting notes"

Architecture

src/jxa_mail_mcp/
├── __init__.py         # Exports mcp instance and main()
├── server.py           # FastMCP server and MCP tools
├── config.py           # Environment variable configuration
├── builders.py         # QueryBuilder for constructing JXA scripts
├── executor.py         # JXA script execution utilities
└── jxa/
    ├── __init__.py     # Exports MAIL_CORE_JS
    └── mail_core.js    # Shared JXA utilities library

Design Principles

1. Separation of concerns: Python handles logic/types, JavaScript handles Mail.app interaction
2. Builder pattern: QueryBuilder constructs optimized JXA scripts programmatically
3. Shared JS library: mail_core.js provides reusable utilities injected into all scripts
4. Type safety: Python type hints ensure correct usage

Performance

The Problem

Naive AppleScript/JXA iteration is extremely slow:

// SLOW: ~54 seconds for a few hundred messages
for (let msg of inbox.messages()) {
    results.push({
        from: msg.sender(),      // IPC call to Mail.app
        subject: msg.subject(),  // IPC call to Mail.app
    });
}

Each property access triggers a separate Apple Event IPC round-trip.

The Solution: Batch Property Fetching

JXA supports fetching a property from all elements at once:

// FAST: ~0.6 seconds (87x faster)
const msgs = inbox.messages;
const senders = msgs.sender();   // Single IPC call returns array
const subjects = msgs.subject(); // Single IPC call returns array

for (let i = 0; i < senders.length; i++) {
    results.push({ from: senders[i], subject: subjects[i] });
}

Benchmark Results

Method	Time	Speedup
AppleScript (per-message)	54.1s	1x
JXA (per-message)	53.9s	1x
JXA (batch fetching)	0.62s	87x

Fuzzy Search Performance

Fuzzy search uses trigrams for fast candidate selection and Levenshtein distance for accurate ranking. Tested on a mailbox with ~6,000 emails:

Search Type	Time	Overhead
Regular search	~360ms	-
Fuzzy search	~480ms	+33%

The trigram pre-filtering keeps fuzzy search fast by avoiding expensive Levenshtein calculations on non-matching words.

Example: Searching for "reserch studies" (typo) correctly finds "research studies" with 0.94 similarity score.

Development

uv sync
uv run ruff check src/
uv run ruff format src/

# Test
uv run python -c "
from jxa_mail_mcp.server import list_accounts, get_todays_emails
print('Accounts:', len(list_accounts()))
print('Today:', len(get_todays_emails()))
"

License

GPL-3.0-or-later