postfix copilot-instructions.md

Repository instructions for a Ruby Chef cookbook, which automates software installation and system configuration.

In plain words
What is it for?
Finding recipes, resources, templates, and tests; checking platform support; and preparing or validating cookbook changes.
Why use it?
They explain the cookbook's files, supported platforms, environment requirements, and testing tools so changes fit the project.

Instructions file for GitHub Copilot

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/sous-chefs/postfix/copilot-instructions
Clone the repo
git clone --depth 1 https://github.com/sous-chefs/postfix

Made for: GitHub Copilot.

Per session 1,015 This file is loaded in full into every session.
When invoked 1,015 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 $0.01015 $0.01015
Opus 5 $0.00508 $0.00508
Sonnet 5 $0.00203 $0.00203
Haiku 4.5 $0.00102 $0.00102

Measured 2d ago against content hash 5fef7f2ec462, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

postfix copilot-instructions.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.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

.github/copilot-instructions.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Copilot Instructions for Sous Chefs Cookbooks

Repository Overview

Chef cookbook for managing software installation and configuration. Part of the Sous Chefs cookbook ecosystem.

Key Facts: Ruby-based, Chef >= 16 required, supports various OS platforms (check metadata.rb, kitchen.yml and .github/workflows/ci.yml for which platforms to specifically test)

Project Structure

Critical Paths:

  • recipes/ - Chef recipes for cookbook functionality (if this is a recipe-driven cookbook)
  • resources/ - Custom Chef resources with properties and actions (if this is a resource-driven cookbook)
  • spec/ - ChefSpec unit tests
  • test/integration/ - InSpec integration tests (tests all platforms supported)
  • test/cookbooks/ or test/fixtures/ - Example cookbooks used during testing that show good examples of custom resource usage
  • attributes/ - Configuration for recipe driven cookbooks (not applicable to resource cookbooks)
  • libraries/ - Library helpers to assist with the cookbook. May contain multiple files depending on complexity of the cookbook.
  • templates/ - ERB templates that may be used in the cookbook
  • files/ - files that may be used in the cookbook
  • metadata.rb, Berksfile - Cookbook metadata and dependencies

Build and Test System

Environment Setup

MANDATORY: Install Chef Workstation first - provides chef, berks, cookstyle, kitchen tools.

Essential Commands (strict order)

berks install                   # Install dependencies (always first)
cookstyle                       # Ruby/Chef linting
yamllint .                      # YAML linting
markdownlint-cli2 '**/*.md'     # Markdown linting
chef exec rspec                 # Unit tests (ChefSpec)
# Integration tests will be done via the ci.yml action. Do not run these. Only check the action logs for issues after CI is done running.

Critical Testing Details

  • Kitchen Matrix: Multiple OS platforms × software versions (check kitchen.yml for specific combinations)
  • Docker Required: Integration tests use Dokken driver
  • CI Environment: Set CHEF_LICENSE=accept-no-persist
  • Full CI Runtime: 30+ minutes for complete matrix

Read the full file on GitHub · 96 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 · 96 lines · 1,015 tokens per session scan A 5fef7f2ec462

Subscribe to this mod's changes

postfix copilot-instructions.md is an instructions file published in the GitHub repository sous-chefs/postfix (102 stars, last pushed 20d ago), licensed Apache-2.0. It adds 1,015 tokens to every session, about $0.0051 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.