Borrowing it
Nothing to install: this file belongs to TheTom/elm327_obd_for_mac. 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/TheTom/elm327_obd_for_mac/main/CLAUDE.mdgit clone --depth 1 https://github.com/TheTom/elm327_obd_for_macWrote 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/thetom/elm327_obd_for_mac/claude-md)<a href="https://agentmods.dev/instructions/thetom/elm327_obd_for_mac/claude-md"><img src="https://agentmods.dev/badge/instructions/thetom/elm327_obd_for_mac/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 | $0.04418 | $0.04418 |
| Opus 5 | $0.02209 | $0.02209 |
| Sonnet 5 | $0.00884 | $0.00884 |
| Haiku 4.5 | $0.00442 | $0.00442 |
Grade A, and why
elm327_obd_for_mac 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 8d 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 — 653 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
Ford Diagnostic Tool — Autonomous Development Rules
Native macOS Ford Diagnostic Tool — a Rust CLI that communicates directly with ELM327 USB adapters for Ford-specific OBD-II and UDS diagnostics on Apple Silicon. No Wine, no Windows. See PRD.md for full product spec.
Core thesis:
Most Ford owners can't run FORScan on macOS without painful Wine hacks. Build a native Rust tool that talks directly to ELM327 adapters and the truck's CAN bus.
This repository is developed using test-driven, autonomous execution with strict guardrails.
Core Operating Principles
- Tests before implementation — mandatory.
- Every piece of work must correspond to a GitHub Issue.
- Implement the smallest working solution.
- No unsafe unless justified — if you write
unsafe, comment why. - Keep architecture simple and extensible.
- Keep the repository compilable at all times.
- Maintain organized documentation, repository maps, and test maps.
- Follow the issue → failing tests → implementation → review → commit → close issue loop.
- Focus on serial communication, ELM327 protocol, OBD-II, and Ford-specific diagnostics.
- If uncertain about a requirement, create a GitHub Issue and continue with other unblocked work.
GitHub Issue-Driven Development (MANDATORY)
This project uses GitHub Issues as the bug/task system, modeled after Google Buganizer.
Every unit of work is treated as an issue.
This includes:
- features
- bugs
- implementation tasks
- investigations
- product questions
- refactors
- architectural decisions
- hardware compatibility findings
Issue Requirement (MANDATORY)
Before starting any work:
- Ensure a GitHub Issue exists
- Assign the correct priority label
- Assign the correct type label
- Assign the correct area label(s)
- Write failing tests
- Only then may implementation begin
No task may be worked on without a corresponding issue.
Priority Labels (Buganizer Style)
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.
- 8d ago First seen · 653 lines · 4,418 tokens per session scan A 8c60997992bd
elm327_obd_for_mac CLAUDE.md is an instructions file published in the GitHub repository TheTom/elm327_obd_for_mac (12 stars, last pushed 5mo ago), licensed Apache-2.0. It adds 4,418 tokens to every session, about $0.0221 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.
Other instructions, from other repositories
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.