Apple Mail MCP Server

An MCP server that provides programmatic access to Apple Mail, enabling AI assistants like Claude to read, send, search, and manage emails on macOS.

⚠️ Pre-1.0 — expect breaking changes. The MCP tool surface (tool names, parameters, return shapes) is still evolving as the project matures. Pin to a specific version (for example, apple-mail-fast-mcp==0.10.2) and review the CHANGELOG before upgrading.

Tools (24)

Grouped by lifecycle (10 read-only, 14 mutating):

• Discovery — list_accounts, list_mailboxes, list_rules, list_templates: enumerate what's configured (no external cache — call per account).
• Read — search_messages, get_messages, get_thread, get_attachment_content, get_template, render_template: read messages/threads, pull an attachment's content inline, and render templates.
• Message actions — update_message (read/flag/move in one pass), delete_messages (→ Trash), save_attachments (to disk, byte-capped).
• Drafts — create_draft (new / reply / forward, optionally send_now), update_draft, delete_draft.
• Mailbox CRUD — create_mailbox, update_mailbox (rename or move), delete_mailbox.
• Rules — create_rule, update_rule, delete_rule.
• Templates (write) — save_template, delete_template.

Destructive operations (delete_*, create_rule with move/forward/delete actions, create_draft with send_now=true) prompt for confirmation via MCP elicitation. See docs/reference/TOOLS.md for full parameters and return shapes.

Prerequisites

• macOS 10.15 (Catalina) or later
• Python 3.10 or later
• Apple Mail configured with at least one account
• uv (recommended) or pip

Installation

# From source (recommended for development)
git clone https://github.com/s-morgan-jeffries/apple-mail-fast-mcp.git
cd apple-mail-fast-mcp
uv sync --dev

Configuration

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json). uv sync installs a console script at .venv/bin/apple-mail-fast-mcp; point Claude Desktop at its absolute path — it's the most reliable form under Claude Desktop's restricted spawn environment (no reliance on uv being on PATH):

{
  "mcpServers": {
    "apple-mail": {
      "command": "/path/to/apple-mail-fast-mcp/.venv/bin/apple-mail-fast-mcp"
    }
  }
}

(Equivalent alternative if you prefer driving it through uv: "command": "uv", "args": ["--directory", "/path/to/apple-mail-fast-mcp", "run", "apple-mail-fast-mcp"].)

Optional: split read / write servers

Claude Desktop prompts per-tool for permission. If you want to batch-approve the 9 read tools (list / search / get) and still gate the 14 mutating tools per call, run the connector twice — once with --read-only, once without — under two separate mcpServers entries:

{
  "mcpServers": {
    "apple-mail-read": {
      "command": "/path/to/apple-mail-fast-mcp/.venv/bin/apple-mail-fast-mcp",
      "args": ["--read-only"]
    },
    "apple-mail-write": {
      "command": "/path/to/apple-mail-fast-mcp/.venv/bin/apple-mail-fast-mcp"
    }
  }
}

The --read-only server exposes only the 9 read tools, so Claude Desktop's per-server permission UI naturally groups them. The full server still gates writes individually. Trade-off: 2× connector processes. See docs/reference/TOOLS.md for the per-tool classification and a note on MCP annotation hints (readOnlyHint / destructiveHint / idempotentHint) which forward-compatible hosts may use to provide the same UX without the split.

Permissions

On first run, macOS will prompt for Automation access. Grant permission in: System Settings > Privacy & Security > Automation > Terminal (or your IDE)

Optional: faster search via IMAP

search_messages works out of the box via AppleScript. For large mailboxes (thousands of messages), AppleScript's whose clause can take 1–5 seconds per query. If you want faster server-side search, you can enable IMAP delegation per account by adding a Keychain entry.

How it works. If credentials exist for an account, the server uses IMAP (fast, server-side SEARCH). Otherwise — or on any IMAP failure (offline, wrong password, timeout) — it silently falls back to AppleScript. You never lose functionality; you only gain speed when IMAP is configured and reachable. The normal opt-in is a Keychain entry (below); an environment-variable fallback (further down) covers contexts where the Keychain isn't usable.

One-time setup per account.

1. Generate an app-specific password at your provider. The procedure varies:

   • iCloud: appleid.apple.com/account/manage → App-Specific Passwords. Requires 2FA on your Apple ID (default).
   • Gmail: myaccount.google.com/apppasswords. Requires 2-Step Verification on your Google account.
   • Yahoo / Fastmail / AOL: generate an app password in the provider's account-security settings.

2. Run the setup-imap subcommand. It prompts for the password (no echo), writes the Keychain entry, and verifies by connecting:

   hljs language-bash

   Copy

   apple-mail-fast-mcp setup-imap --account iCloud
   

   Substitute the Mail.app account name exactly — whatever it's labeled in Mail.app (e.g. iCloud, Gmail, "Yahoo!"). The CLI:

   • looks up the account's primary email from Mail.app (override with --email, which is persisted so runtime uses the same login — see the iCloud quirk below),
   • prompts via getpass so the password never lands in shell history,
   • writes to Keychain at apple-mail-fast-mcp.imap.<account> (idempotent — re-running with a new password updates the existing entry; pre-rename apple-mail-mcp.imap. entries still resolve via a read-through fallback removed at 1.0.0),
   • opens an IMAP connection and runs a real LOGIN to confirm the password works. On rejection it rolls back the Keychain entry so you can retry without leaving a broken item behind.

3. If you see a one-time "security wants to use the 'login' keychain" prompt on the next IMAP-backed call, click Always Allow.

To remove the entry later: apple-mail-fast-mcp setup-imap --account iCloud --uninstall.

Environment-variable fallback (uvx / headless / CI)

Some contexts have no usable Keychain: uvx runs (ephemeral binary paths break the Keychain ACL, causing re-prompts or failures), Docker / CI (no Keychain at all), and background services (the ACL prompt blocks forever with no UI attached). For those, you can supply the IMAP password via an environment variable instead:

APPLE_MAIL_MCP_IMAP_PASSWORD_<SUFFIX>

<SUFFIX> is the Mail.app account name uppercased, with each run of non-alphanumeric characters collapsed to a single underscore and leading/trailing underscores trimmed:

When set to a non-empty value, the env var is used in preference to any Keychain entry for that account (it's checked first, with no security shell-out). An empty or whitespace-only value is ignored and the Keychain path is used. The lookup composes with the name↔UUID fallback, so an env var keyed on the account name is still found when a caller passes the account's UUID.

⚠️ Security tradeoff. Environment variables are far less private than the Keychain — they're visible via ps -E, launchctl getenv, /proc-style introspection, and process crash dumps, and they're easy to leak into logs or shell history. Use this only when the Keychain genuinely isn't an option (uvx, Docker, CI, headless). For Claude Desktop and standard local installs, stick with setup-imap + Keychain.

Caveat: the name→suffix mapping isn't reversible — Yahoo! and Yahoo both map to YAHOO, and an account name with no ASCII letters/digits has no env-var form (use the Keychain for those).

Verifying the setup. The setup-imap command does this for you. If you want to spot-check post-hoc:

uv run python -c "from apple_mail_mcp.mail_connector import AppleMailConnector; \
    print(AppleMailConnector().search_messages(account='<ACCOUNT_NAME>', limit=1))"

If IMAP is working, the call returns in ~1 second. If it logs a WARNING about falling back (visible with --log-level=DEBUG), check that the account name matches Mail.app's account name exactly and that the email in your Keychain entry matches what email addresses of account returns.

Known provider quirks.

• iCloud: the IMAP server accepts @icloud.com / @me.com aliases as LOGIN username, not the Apple ID email. The server (and setup-imap) reads email addresses of account from Mail.app for that reason. If your iCloud Apple ID is a third-party address (e.g. a @gmail.com Apple ID) and Mail.app reports no @icloud.com address for the account, auto-detection can't find the right login — setup-imap will fail with a hint to re-run with --email <your @icloud.com/@me.com address>. That --email value is persisted (in ~/.apple_mail_mcp/imap_login_overrides.json) so runtime resolution uses the same login (#341). It's a general override — use it for any account whose auto-detected IMAP login is wrong.
• Yahoo: app passwords have been progressively deprecated; the option may not be available for all accounts. If Yahoo's account-security page doesn't show the option, IMAP setup isn't possible for that account and AppleScript is the only path.
• Gmail: requires 2-Step Verification enabled. If your Google Workspace admin has disabled app passwords at the tenant level, IMAP setup isn't possible for that account.
• Gmail thread retrieval — All Mail visibility tradeoff. find_thread_members (used internally by thread-aware queries) is fastest when [Gmail]/All Mail is exposed over IMAP — that path is ~5 round-trips, mailbox-count-independent. Many users hide All Mail (Gmail Settings → Forwarding and POP/IMAP → Folder size limits → "Do not show in IMAP") because it duplicates every message. When hidden, the connector falls back to a per-mailbox X-GM-THRID iteration (still ~6× faster than the universal BFS, but proportional to your label count — ~25s on a 92-label account). Expose All Mail if you want the headline speed; keep it hidden if you prefer the cleaner IMAP folder list.

Write operations (create_draft, update_draft, including the send_now=true send path) always use AppleScript regardless of IMAP configuration — these need Mail.app's compose UI.

Development

# Setup
uv sync --dev

# Common commands
make test              # Run unit tests
make lint              # Lint with ruff
make typecheck         # Type check with mypy
make check-all         # All checks (lint, typecheck, test, complexity, version-sync, parity)
make coverage          # Coverage report
make test-integration  # Integration tests (requires Mail.app)

# Validation scripts
./scripts/check_version_sync.sh          # Version consistency
./scripts/check_client_server_parity.sh  # Connector-server alignment
./scripts/check_complexity.sh            # Cyclomatic complexity
./scripts/check_applescript_safety.sh    # AppleScript safety audit

Branch Convention

{type}/issue-{num}-{description} — e.g., feature/issue-42-thread-support

Architecture

server.py (FastMCP tools — thin orchestration, validation, elicitation gates)
  -> mail_connector.py (dispatch + domain logic)
     -> AppleScript path:  subprocess.run(["osascript", ...]) -> Apple Mail.app   (universal baseline)
     -> IMAP fast path:    imap_connector.py -> the account's IMAP server          (when hinted + Keychain creds)

Dispatch model. AppleScript is the always-available baseline. When a read/mutation call supplies an account (and, where relevant, mailbox) hint and the account has Keychain IMAP credentials, the connector takes a server-side IMAP fast path; on any IMAP failure it falls back to AppleScript, so you never lose functionality — you only gain speed. See docs/reference/ARCHITECTURE.md for the full dispatch model, the dual-emit message-ID scheme, the drafts lifecycle, and the IMAP thread tiers.

• server.py — MCP tool registration, input validation, confirmation (elicitation) gates, response formatting
• mail_connector.py — AppleScript generation/execution + IMAP-fast-path dispatch
• imap_connector.py — IMAP client + connection pool (search, fetch, bulk-mutation fast paths)
• security.py — Input sanitization, audit logging, confirmation flows
• utils.py — Pure functions: escaping, parsing, validation
• exceptions.py — Typed exception hierarchy

Security

• Local execution only (no cloud processing)
• Uses existing Mail.app authentication; IMAP app-passwords (opt-in) live in the macOS Keychain, never in the repo or config
• All inputs sanitized and AppleScript-escaped (defense against AppleScript injection)
• Destructive operations require user confirmation via MCP elicitation; rate limits + audit logging on top
• save_attachments is byte-capped (per-attachment + aggregate) against disk-fill DoS

Docs:

• SECURITY.md — vulnerability-reporting policy
• docs/SECURITY.md — user-facing security posture & privacy
• docs/guides/THREAT_MODEL.md — STRIDE trust-boundary analysis
• docs/guides/SECURITY_CHECKLIST.md — per-feature contributor checklist

Contributing

See CONTRIBUTING.md for development workflow, coding standards, and PR process.

License

MIT