apple-mail-mcp: Instructions file for Claude Code

CLAUDE.md

apple-mail-mcp CLAUDE.md is an instructions file for Claude Code from BastianZim/apple-mail-mcp. It costs 412 tokens per session, scanned A, original, MIT.

A project instruction file for an Apple Mail MCP server, a tool that reads email data for other software on macOS.

In plain words
What is it for?
It is for developing or testing a Python server that reads Apple Mail's SQLite metadata and .emlx message files, converts dates, decodes headers, and falls back from HTML to text.
Why use it?
It explains the repository's read-only design, commands, tests, and division between the MCP server and the Mail database reader.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md; mentions Claude Code.

This is BastianZim/apple-mail-mcp's own configuration. It tells Claude Code how to work on apple-mail-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything apple-mail-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to BastianZim/apple-mail-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/BastianZim/apple-mail-mcp/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/BastianZim/apple-mail-mcp

Made for: Claude Code.

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README.md
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Per session 412 This file is loaded in full into every session.
When invoked 412 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00412 $0.00412
Opus 5 $0.00206 $0.00206
Sonnet 5 $0.00082 $0.00082
Haiku 4.5 $0.00041 $0.00041

Measured 9d ago against content hash 5563bed91f0e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

apple-mail-mcp CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 40 lines

What it actually says

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project overview

Read-only MCP server for Apple Mail on macOS. Reads email metadata from Mail's SQLite database (~/Library/Mail/V10/MailData/Envelope Index) and message bodies from .emlx files. No AppleScript dependency. Designed for large mailboxes (100K+ messages).

Commands

# Run the server
uv run apple-mail-mcp

# Install dependencies
uv sync

# Run tests
uv run --group dev pytest tests/ -v

# Run a single test
uv run --group dev pytest tests/test_maildb.py::TestCoreDataToIso::test_known_date -v

Architecture

Two-module design under apple_mail_mcp/:

  • server.py — MCP tool definitions using FastMCP. Lazily initializes a single MailDatabase instance. Each tool returns JSON strings. Entry point: main().
  • maildb.pyMailDatabase class. All data access lives here: read-only SQLite connections, .emlx file parsing, timestamp conversion (Core Data epoch → ISO 8601), MIME header decoding, HTML-to-text fallback.

Data flow: MCP tool → _get_db()MailDatabase method → SQLite query + optional .emlx read → JSON response.

Key details:

  • SQLite is opened read-only via URI (?mode=ro)
  • .emlx lookup: at startup, MailDatabase caches all Messages/ directories (typically 10–50). Finding a message is O(dirs) stat calls, not a filesystem search.
  • Core Data timestamps are offset by 978307200 seconds from Unix epoch
  • Only dependency beyond stdlib: mcp SDK (uses mcp.server.fastmcp.FastMCP)
  • Build system: hatchling
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 40 lines · 412 tokens per session scan A 5563bed91f0e

Subscribe to this mod's changes

apple-mail-mcp CLAUDE.md is an instructions file published in the GitHub repository BastianZim/apple-mail-mcp (2 stars, last pushed 2mo ago), licensed MIT. It adds 412 tokens to every session, about $0.0021 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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