plumbline CLAUDE.md

plumbline CLAUDE.md is an instructions file for coding agents from sroberts/plumbline. It costs 1,706 tokens per session, scanned A, original, MIT.

A project guide for Claude Code, an AI coding assistant, that explains the repository’s status, architecture, build commands, tests, and files that are generated rather than edited by hand.

In plain words
What is it for?
Use it when asking Claude Code to understand, build, test, or modify the Plumbline Go command-line application.
Why use it?
It gives the assistant the project’s rules and implementation contract before it changes code, reducing guesswork and accidental edits to derived files.

Instructions file

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/sroberts/plumbline/claude-md
Clone the repo
git clone --depth 1 https://github.com/sroberts/plumbline

Wrote 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.

agentmods badge for plumbline CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/sroberts/plumbline/claude-md.svg)](https://agentmods.dev/instructions/sroberts/plumbline/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/sroberts/plumbline/claude-md"><img src="https://agentmods.dev/badge/instructions/sroberts/plumbline/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,706 This file is loaded in full into every session.
When invoked 1,706 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.01706 $0.01706
Opus 5 $0.00853 $0.00853
Sonnet 5 $0.00341 $0.00341
Haiku 4.5 $0.00171 $0.00171

Measured 5d ago against content hash a0e7564438a4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

plumbline 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 5d 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 · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 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 status

Plumbline is implemented and shipping. It is a Go module (github.com/sroberts/plumbline, Go 1.26.1) with a Cobra CLI, a Bubble Tea TUI, a 22-signal detector catalog, GoReleaser packaging, and eight CI workflows. It assesses itself at ACMM Level 5.

SPEC.md is the implementation contract — numbered sections, cited throughout the source (SPEC.md §6 = signal model, §7 = scoring, §9 = output formats). Read the relevant section before changing behavior it pins. The ACMM paper is the model source; SPEC.md is what plumbline actually does, and §6's "Deviations from the source paper" records where the two diverge on purpose.

Build & test

make build      # binary with version ldflags
make test       # unit + E2E
make test-race  # race detector
make lint       # gofmt + go vet (golangci-lint if installed)

CONTRIBUTING.md has the full pre-PR checklist and the package-by-package "where things live" map — read it rather than rediscovering the layout.

Architecture in brief

  • pkg/acmm — the public types. Anything here is --json surface and part of the compatibility contract.
  • internal/scanner — the single IO chokepoint. Signals read the RepoIndex, never the filesystem directly.
  • internal/signals/lN/<id>.go — one file per detector, self-registering via init(). The level packages are blank-imported from cmd/plumbline/registrations.go and cmd/gen-signal-docs/main.go; a new level package needs adding to both.
  • internal/signals.Fixer — an optional interface. Most signals don't implement it, and plumbline fix <id> correctly exits 2 for those. Don't add a fixer for a signal whose remedy needs real judgment (which monitoring SDK, which triage rules) — the fix_hint prose is the answer there.
  • internal/fix — the only place plumbline writes inside a target repo. Refuses overwrite; in-repo paths only.

Read the full file on GitHub · 102 lines

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. 5d ago First seen · 102 lines · 1,706 tokens per session scan A a0e7564438a4

Subscribe to this mod's changes

plumbline CLAUDE.md is an instructions file published in the GitHub repository sroberts/plumbline (6 stars, last pushed 4d ago), licensed MIT. It adds 1,706 tokens to every session, about $0.0085 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.