Borrowing it
Nothing to install: this file belongs to piperbox/piper. 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/piperbox/piper/main/AGENTS.mdgit clone --depth 1 https://github.com/piperbox/piperWrote 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/piperbox/piper/agents-md)<a href="https://agentmods.dev/instructions/piperbox/piper/agents-md"><img src="https://agentmods.dev/badge/instructions/piperbox/piper/agents-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/piperbox/piper/agents-md"><img src="https://agentmods.dev/badge/instructions/piperbox/piper/agents-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 | $0.00385 | $0.00385 |
| Opus 5.5 | $0.00154 | $0.00154 |
| Sonnet 5.5 | $0.00077 | $0.00077 |
| Haiku 4.5 | $0.00038 | $0.00038 |
Grade A, and why
piper AGENTS.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 2mo 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.
What it actually says
AGENTS.md
Read CLAUDE.md in full first — it is the authoritative source for coding principles, commands, constraints, layering, and branch/PR/issue workflow. This file only captures high-signal facts an agent would otherwise get wrong that aren't obvious from filenames or CLAUDE.md.
- Single package:
go test ./internal/store/.... Single test:go test ./internal/store -run TestName. - Before claiming work is done, run the full CI sequence:
gofmt -l .(it must print nothing),go vet ./...,make test, thenmake cross.make testandmake crossalone do not catch formatting or vet failures. - For unit tests of code that depends on
runtime.Runtime, useinternal/runtime.FakeRuntimefrominternal/runtime/fake.go. Real Docker is reserved for Docker integration and e2e tests, which must skip cleanly when Docker is unavailable. - Runtime environment configuration belongs in
internal/config; production packages must not callos.Getenvinline. TestEndToEndDeployfailing with "no response through Caddy" is usually not a code bug: any other Caddy holding:80/:2019serves the request from its own empty route table, and Caddy'sSO_REUSEPORTlets piperd's embedded instance bind alongside it with no error. Runlsof -nP -iTCP:80 -iTCP:2019 -sTCP:LISTENand kill any straycaddy/piperdfirst.- The layering rule is enforced by
test/arch. Adding aninternal/package means giving it a rank there; if a change needs that map edited to pass, check whether the new import is the actual mistake.
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.
- 2mo ago First seen · 11 lines · 385 tokens per session scan A 8b623bc59e55
piper AGENTS.md is an instructions file published in the GitHub repository piperbox/piper (10 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 385 tokens to every session, about $0.0015 per session on Opus 5.5. 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.
Other instructions, from other repositories
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).
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.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
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.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deno copilot-instructions.md
Copilot instructions for denoland/deno, covering deno development guide for github copilot, network access, high level overview, key directories and key files to understand first.