pi AGENTS.md

pi AGENTS.md is an instructions file for Codex, OpenCode from TGYD-helige/pi. It costs 4,423 tokens per session, scanned A, original, Apache-2.0.

A set of coding rules for a monorepo, a single repository containing several related packages, shared code, and tests. It guides work on Pi extensions, which are TypeScript modules that add behavior to the Pi agent runtime.

In plain words
What is it for?
It helps develop and test Pi extensions by checking existing packages and shared utilities, following a minimal-change process, and tracing the affected code before editing.
Why use it?
It helps keep changes small and avoids adding duplicate code, unnecessary dependencies, or new features that the project does not need.

Instructions file for CodexOpenCode

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/tgyd-helige/pi/agents-md
Clone the repo
git clone --depth 1 https://github.com/TGYD-helige/pi

Made for: Codex, OpenCode.

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 pi AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/tgyd-helige/pi/agents-md.svg)](https://agentmods.dev/instructions/tgyd-helige/pi/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/tgyd-helige/pi/agents-md"><img src="https://agentmods.dev/badge/instructions/tgyd-helige/pi/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 4,423 This file is loaded in full into every session.
When invoked 4,423 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 $0.04423 $0.04423
Opus 5 $0.02211 $0.02211
Sonnet 5 $0.00885 $0.00885
Haiku 4.5 $0.00442 $0.00442

Measured 5d ago against content hash a654f322e44b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

pi 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 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.

AGENTS.md · 404 lines

How it starts

The opening of the file, as written. The whole thing — 404 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Pi Extensions Monorepo — Agent Guidelines

Project Overview

This monorepo contains Pi extensions (packages/pi-*), a shared library (packages/shared), and integration tests (tests/). Most packages are Pi extensions — TypeScript modules that hook into the Pi agent runtime.


Required Agent Skills

Two external skill sets are mandatory when developing in this repo. Install them for your harness before starting work; if your harness cannot install skills, follow the rules inlined below.

ponytail — minimal-code discipline

https://github.com/DietrichGebert/ponytail

Every code change follows ponytail's ladder — stop at the first rung that holds:

1. Does this need to exist?   → no: skip it (YAGNI)
2. Already in this codebase?  → reuse it, don't rewrite (check sibling packages and packages/shared first)
3. Stdlib does it?            → use it
4. Native platform feature?   → use it
5. Installed dependency?      → use it — no new deps for one-call problems
6. One line?                  → one line
7. Only then: the minimum that works

The ladder runs after understanding the problem, never instead of it: read the code the change touches and trace the real flow before picking a rung. Lazy about the solution, never about reading — and never about trust-boundary validation, data-loss handling, security, or accessibility.

Install:

  • Claude Code: /plugin marketplace add DietrichGebert/ponytail, then /plugin install ponytail@ponytail (two separate prompts)
  • Codex: codex plugin marketplace add DietrichGebert/ponytail && codex plugin add ponytail@ponytail, then trust its two lifecycle hooks under /hooks

mattpocock/skills — engineering workflow skills

https://github.com/mattpocock/skills

Use this skill set for process work in this repo:

  • triage — processing new issues/PRs (labels: the type/* + P0P3 set managed by .github/workflows/labeler.yml)
  • to-spec / to-tickets — before non-trivial implementations
  • tdd — behavior changes in packages with existing coverage (see Unit Test Convention)
  • diagnosing-bugs — no fix without a reproduced root cause
  • research, code-review, resolving-merge-conflicts — as named

Read the full file on GitHub · 404 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 · 404 lines · 4,423 tokens per session scan A a654f322e44b

Subscribe to this mod's changes

pi AGENTS.md is an instructions file published in the GitHub repository TGYD-helige/pi (59 stars, last pushed 3d ago), licensed Apache-2.0. It adds 4,423 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.