Borrowing it
Nothing to install: this file belongs to wyattjoh/imessage-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.
curl -O https://raw.githubusercontent.com/wyattjoh/imessage-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/wyattjoh/imessage-mcpWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/wyattjoh/imessage-mcp/claude-md)<a href="https://agentmods.dev/instructions/wyattjoh/imessage-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/wyattjoh/imessage-mcp/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/wyattjoh/imessage-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/wyattjoh/imessage-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.01141 | $0.01141 |
| Opus 5 | $0.00571 | $0.00571 |
| Sonnet 5 | $0.00228 | $0.00228 |
| Haiku 4.5 | $0.00114 | $0.00114 |
Grade A, and why
imessage-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.
How it starts
The opening of the file, as written. The whole thing — 125 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Development Commands
This is a Deno workspace monorepo with two packages:
packages/imessage- Core library for iMessage database accesspackages/imessage-mcp- MCP server implementation
Root Commands (affects all packages)
# Cache dependencies for all packages
deno cache packages/*/mod.ts
# Code quality (runs on all packages)
deno task fmt # Format all code
deno task lint # Lint all packages
deno task check # Type check all TypeScript files
# Run tests
deno task test
# Publish packages to JSR (CI/CD)
deno publish
Package-Specific Commands
# Run the MCP server
cd packages/imessage-mcp
deno run --allow-read --allow-env --allow-sys --allow-ffi mod.ts
# Development with file watching
cd packages/imessage-mcp
deno run --allow-read --allow-env --allow-sys --allow-ffi --watch mod.ts
# Test the core library
cd packages/imessage
deno test --allow-read --allow-env --allow-ffi --allow-sys=homedir
Architecture Overview
This monorepo contains a Model Context Protocol (MCP) server and core library that provide read-only access to the macOS iMessage database. The codebase follows functional programming principles with no classes.
Package Structure
-
@wyattjoh/imessage (
packages/imessage/)- Core library for iMessage database access
- Database operations, type definitions, and utilities
- No MCP dependencies - can be used standalone
-
@wyattjoh/imessage-mcp (
packages/imessage-mcp/)- MCP server implementation
- Imports and uses the core library
- Provides LLM-accessible tools
Core Components
- MCP Server Layer (
packages/imessage-mcp/src/index.ts)- Creates MCP server instance using
@modelcontextprotocol/sdk - Defines 6 tools with Zod schemas for validation
- Uses StdioServerTransport for communication
- Lazy database initialization pattern
- Creates MCP server instance using
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.
- 9d ago First seen · 125 lines · 1,141 tokens per session scan A 63afc45934a7
imessage-mcp CLAUDE.md is an instructions file published in the GitHub repository wyattjoh/imessage-mcp (29 stars, last pushed 21d ago), licensed MIT. It adds 1,141 tokens to every session, about $0.0057 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 2026-08-30.
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