UsageRules

UsageRules is a development tool for Elixir projects that helps gather and consolidate usage rules from dependencies. The package provides Mix tasks to collect documentation from dependencies that have usage-rules.md files and combine them into a single rules file for your project.

You'll note this package itself doesn't have a usage-rules.md. Its a simple tool that likely would not benefit from having a usage-rules.md file.

For Package Authors

Even if you don't want to use LLMs, its very possible that your users will, and they will often come to you with hallucinations from their LLMs and try to get your help with it. Writing a usage-rules.md file is a great way to stop this sort of thing 😁

Key Features

1. Dependency Rules Collection: Automatically discovers and collects usage rules from dependencies that provide usage-rules.md files in their package directory
2. Rules Consolidation: Combines multiple package rules into a single file with proper sectioning and markers
3. Status Tracking: Can list dependencies with usage rules and check if your consolidated file is up-to-date
4. Selective Management: Allows adding/removing specific packages from your rules file

How It Works

1. The tool scans your project's dependencies (in deps/ directory)
2. Looks for usage-rules.md files in each dependency
3. Consolidates these rules into a target file with special markers like <-- package-name-start --> and <-- package-name-end -->
4. Maintains sections that can be updated independently as dependencies change

This is particularly useful for projects using frameworks like Ash, Phoenix, or other packages that provide specific usage guidelines, coding patterns, or best practices that should be followed consistently across your project.

Usage

The main task Mix.Tasks.UsageRules.Sync provides several modes of operation:

Combine specific packages

mix usage_rules.sync rules.md ash phoenix

Gather all dependencies with usage rules

mix usage_rules.sync rules.md --all

List available packages with usage rules

mix usage_rules.sync --list

Check status against a file

mix usage_rules.sync rules.md --list

Remove packages from a file

mix usage_rules.sync rules.md ash --remove

Installation

With Igniter

mix igniter.install usage_rules.

Add the dependency manually

def deps do
  [
    # should only ever be used as a dev dependency
    # requires igniter as a dev dependency
    {:usage_rules, "~> 0.1", only: [:dev]},
    {:igniter, "~> 0.6", only: [:dev]}
  ]
end