piper CLAUDE.md

A project instruction file for Piper, an open-source platform-as-a-service that deploys code from a Git push to hardware you control.

In plain words
What is it for?
Use it when working on Piper's Go binaries, local container deployments, tunnels, or planned preview and relay features. TDD means writing or using tests to guide development.
Why use it?
It explains the system's parts and development rules before changes are made, reducing guesswork and unnecessary complexity.

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/piperbox/piper/claude-md
Clone the repo
git clone --depth 1 https://github.com/piperbox/piper
Per session 2,684 This file is loaded in full into every session.
When invoked 2,684 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 $0.02684 $0.02684
Opus 5 $0.01342 $0.01342
Sonnet 5 $0.00537 $0.00537
Haiku 4.5 $0.00268 $0.00268

Measured 2d ago against content hash 05115a3d68ee, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

piper 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 2d 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 · 158 lines

How it starts

The opening of the file, as written. The whole thing — 158 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.

What this is

An open-source, developer-first PaaS that gives you git push → live HTTPS URL on hardware you own — including a Raspberry Pi behind CGNAT. A single Go module produces multiple binaries:

  • piperd — the agent that runs on your box (control-plane, deployer, tunnel-client).
  • piper-relay — the optional self-hostable cloud relay (SNI passthrough + tunnel server). Not built yet.
  • piper — the CLI, a thin HTTP client to piperd.

Full design rationale lives in docs/superpowers/specs/ — read it before non-trivial work. Implementation plans live in docs/superpowers/plans/; work is delivered plan-by-plan, task-by-task, TDD-style. Plan 1 of 3 is the agent core, LAN-only (build a Dockerfile → run a container → health-check → serve at http://<app>.piper.localhost via managed Caddy, SQLite state). Plan 2 = relay + outbound tunnel + DNS-01 TLS. Plan 3 = GitHub webhook + PR-preview URLs.

Coding Principles

1. Think Before Coding

Don't assume. Don't hide confusion. Surface tradeoffs.

Before implementing:

  • State your assumptions explicitly. If uncertain, ask.
  • If multiple interpretations exist, present them - don't pick silently.
  • If a simpler approach exists, say so. Push back when warranted.
  • If something is unclear, stop. Name what's confusing. Ask.

2. Simplicity First

Minimum code that solves the problem. Nothing speculative.

  • No features beyond what was asked.
  • No abstractions for single-use code.
  • No "flexibility" or "configurability" that wasn't requested.
  • No error handling for impossible scenarios.
  • If you write 200 lines and it could be 50, rewrite it.
  • Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.

3. Surgical Changes

Touch only what you must. Clean up only your own mess.

When editing existing code:

Read the full file on GitHub · 158 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. 2d ago First seen · 158 lines · 2,684 tokens per session scan A 05115a3d68ee

Subscribe to this mod's changes

piper CLAUDE.md is an instructions file published in the GitHub repository piperbox/piper (10 stars, last pushed 2d ago), licensed Apache-2.0. It adds 2,684 tokens to every session, about $0.0134 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.