Borrowing it
Nothing to install: this file belongs to easytocloud/Mac-letterhead. 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/easytocloud/Mac-letterhead/main/CLAUDE.mdgit clone --depth 1 https://github.com/easytocloud/Mac-letterheadWrote 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/easytocloud/mac-letterhead/claude-md)<a href="https://agentmods.dev/instructions/easytocloud/mac-letterhead/claude-md"><img src="https://agentmods.dev/badge/instructions/easytocloud/mac-letterhead/claude-md.svg" alt="Measured on agentmods" 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 | $0.03974 | $0.03974 |
| Opus 5 | $0.01987 | $0.01987 |
| Sonnet 5 | $0.00795 | $0.00795 |
| Haiku 4.5 | $0.00397 | $0.00397 |
Grade A, and why
Mac-letterhead 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 3d 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 — 301 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.
Project Overview
Mac-letterhead is a macOS utility that merges letterhead templates with PDF and Markdown documents using a drag-and-drop interface. It creates AppleScript droplet applications that users can drop documents onto to automatically apply letterhead templates.
Development Commands
Build and Test Commands
Development Setup:
make dev-install # Install package for local development using uv
make dev-droplet # Create development droplet using local code
Desktop Extension (DXT/MCPB):
make build-dxt # Build the Desktop Extension (.mcpb) for Claude for macOS
# Output: dxt/mac-letterhead-<version>.mcpb
# Requires: Node.js (npx @anthropic-ai/mcpb pack)
Unit Tests (pytest-based software testing):
make test-unit # Run unit tests with default Python version
make test-unit-py3.11 # Run unit tests with specific Python version
make test-all-unit # Run unit tests across all Python versions (3.10, 3.11, 3.12)
Rendering Tests (document generation validation):
make rendering-reportlab-basic # Basic ReportLab rendering (minimal deps)
make rendering-reportlab-enhanced # Enhanced ReportLab with full markdown features
make rendering-weasyprint # High-quality WeasyPrint rendering (requires system deps)
make rendering-backend-matrix # Test all backend/markdown combinations
make rendering-all-python-versions # Test across all Python versions
make test-all-rendering # Run all rendering tests
Quick Tests:
make test-dev # Quick development validation (unit tests only)
make test-smoke # Fast smoke test with single input file
Comprehensive Testing:
make test-all # Run ALL tests (unit + smoke + rendering)
Cleaning:
make clean-all # Clean everything (build artifacts, test files, droplets)
make clean-build # Remove build artifacts and virtual environments only
make clean-droplets # Remove test droplets only
make clean-test-output # Remove test output files (PDFs, HTMLs)
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.
- 3d ago Changed · -1 lines · +102 tokens per session e880ed5ceb72
- 7d ago First seen · 302 lines · 3,872 tokens per session scan A 507d1ef55d18
Mac-letterhead CLAUDE.md is an instructions file published in the GitHub repository easytocloud/Mac-letterhead (1 stars, last pushed 5d ago), licensed MIT. It adds 3,974 tokens to every session, about $0.0199 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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