Project Explainer Skill

Turn any unfamiliar codebase into a clear, GitHub-ready project guide.

Overview

Project Explainer Skill is an npm-distributed Agent Skill for Codex, Claude Code, and other Agent Skills-compatible tools. It installs a reusable project-explainer skill that guides an AI coding agent through repository discovery, stack detection, setup instructions, file-by-file explanation, runtime behavior, and GitHub-ready documentation.

It is designed for developers who want a high-quality README, onboarding guide, repository tour, or handoff document without relying on vague guesses or generic boilerplate.

Key Features

• One-command installer: Installs into Codex, Claude Code, or both with npx project-explainer-skill install all.
• Cross-agent support: Targets Codex skill directories (.agents/skills) and Claude skill directories (.claude/skills).
• User or project scope: Installs globally for the current user or locally inside a specific repository.
• Zero runtime dependencies: Uses only Node.js built-ins: fs, os, and path.
• Safe overwrite behavior: Copies the skill payload into the expected destination with deterministic file replacement.
• GitHub-ready output guidance: The skill prompts agents to explain stack, execution, folder structure, files, user experience, testing, deployment, and assumptions.
• Reference template included: Ships references/report-template.md for consistent long-form project documentation.
• Small package footprint: The npm package contains only the installer, skill files, metadata, and documentation.

Installation

[!IMPORTANT] Requires Node.js 16 or newer. The package is CommonJS and uses fs.cpSync, which is available in modern Node versions.

Install the skill for both Codex and Claude Code:

npx project-explainer-skill install all

Install only for Codex:

npx project-explainer-skill install codex

Install only for Claude Code:

npx project-explainer-skill install claude

Install into the current project instead of your user-level skills folder:

npx project-explainer-skill install all --scope project

Install into a specific project path:

npx project-explainer-skill install codex --scope project --cwd /path/to/repo

Build From Source

This project uses npm and has no external dependencies.

git clone https://github.com/Abdelouahedb/project-explainer-skill.git
cd project-explainer-skill
npm install
npm test
npm pack --dry-run

Quick Start

Install the skill:

npx project-explainer-skill install all

Then ask your agent to use it.

For Codex:

Use $project-explainer to explain this repository and create a GitHub-ready PROJECT_GUIDE.md.

For Claude Code:

/project-explainer

Or ask naturally:

Explain this whole repository, including the tech stack, folder structure, important files, setup commands, and what users see when it runs.

CLI Reference

npx project-explainer-skill install <target> [options]

| Argument | Values | Description | | --- | --- | --- | | <target> | all | Install for Codex and Claude Code. | | <target> | codex | Install only into Codex skill directories. | | <target> | claude | Install only into Claude Code skill directories. |

| Option | Values | Default | Description | | --- | --- | --- | --- | | --scope | user, project | user | Choose whether to install for the current user or into a project directory. | | --cwd | path | current working directory | Project directory used when --scope project is selected. | | --help | none | none | Print installer usage. |

Install Targets

| Agent | User scope | Project scope | | --- | --- | --- | | Codex | ~/.agents/skills/project-explainer | <cwd>/.agents/skills/project-explainer | | Claude Code | ~/.claude/skills/project-explainer | <cwd>/.claude/skills/project-explainer |

[!NOTE] If your agent is already running and does not detect the new skill, restart the agent or reload its skills list.

What The Skill Teaches Agents To Produce

The installed skill guides an agent to create documentation with:

• A high-level project summary
• A precise tech stack breakdown
• Local install, run, test, build, and deployment instructions
• Folder-by-folder and file-by-file explanations
• A description of what users see when the project runs
• Runtime, routing, API, state, or data-flow notes
• Testing and quality-check guidance
• Known unknowns and assumptions instead of invented details

project-explainer-skill/
+-- bin/
|   +-- install.js
+-- agents/
|   +-- openai.yaml
+-- references/
|   +-- report-template.md
+-- SKILL.md
+-- README.md
+-- LICENSE
+-- package.json

The CLI parses install <target> and copies the skill payload into the correct destination directory.

package root
+-- SKILL.md
+-- README.md
+-- agents/
+-- references/

Those files are copied into one or more target folders:

~/.agents/skills/project-explainer
~/.claude/skills/project-explainer
<cwd>/.agents/skills/project-explainer
<cwd>/.claude/skills/project-explainer

The installer uses fs.cpSync(..., { recursive: true, force: true }), so reinstalling updates the existing skill files.

Quality Checks

Run the package smoke test:

npm test

Preview the npm package contents:

npm pack --dry-run

Expected behavior:

• npm test prints the CLI help text.
• npm pack --dry-run includes SKILL.md, README.md, agents/, references/, bin/, package.json, and LICENSE.

Contributing

Open-source contributions are welcome. Keep the skill focused, practical, and useful for real repository documentation.

1. Fork the repository.

2. Branch from main with a focused name:

   git checkout -b improve-installer-docs

3. Commit your changes:

   git commit -m "Improve installer documentation"

4. Push your branch:

   git push origin improve-installer-docs

5. Open a pull request with a short explanation of what changed and why.

License

Released under the MIT License.

Sources

• OpenAI Codex Skills
• Claude Code Skills
• Claude custom skills
• Agent Skills open standard