Codebase Onboarding Guide skill for Claude and Codex

Codebase Onboarding Guide as an AI skill. It asks for Project name and purpose, Tech stack, Repository layout and 4 more, then does the rest. Free to install…

Install it once and Claude or Codex runs it for you. When your request matches, your AI loads the skill, asks for anything it is missing, and works through the template itself. Prefer to fill it in by hand? See the full prompt template.

Download the skill (.zip) · View SKILL.md

When it is used

Use when a new engineer joins a project and needs a guide to running, navigating and safely changing its codebase in the first week. Do not use for generating API reference docs or explaining a single function. Related topics: coding, education.

What it will ask you for

• Project name and purpose (longer free text)
• Tech stack (free text, e.g. "Languages and frameworks and datastores")
• Repository layout (longer free text)
• Setup steps as known today (longer free text)
• Testing and release process (longer free text)
• Team conventions (longer free text)
• Experience of the reader (choose one: Junior, Mid level, Senior new to the stack)

How it works

1. Write the day-one setup with exact commands, a success check for each and the likely failure points.
2. Map each main folder with one sentence on its role and trace one request through the layers.
3. Explain how to make a safe first change: where the test goes, how to run it, how review and release work.
4. Collect domain terms and team conventions a newcomer will meet in the first week.
5. Propose three starter tasks of rising difficulty with who to ask, and mark every gap as to be filled by the team.

What you get

An onboarding guide organised by day, with a setup section, a folder map, a first-change walkthrough, a glossary, three starter tasks and a list of contacts.

What it watches out for

• Guessing commands that were not supplied, which sends a newcomer down a failing setup on day one.
• Listing every folder equally, when the useful guide highlights the few places most changes happen.
• Skipping how code ships, so the first merged change stalls at an unknown release step.

How to install

Claude.ai and the Claude desktop app

1. Download the skill .zip.
2. Open Settings, then Capabilities, and find Skills.
3. Choose Upload skill and select the .zip.
4. Ask Claude for help with the task. It loads the skill when your request matches.

Claude Code

1. Download the skill .zip.
2. Unzip it into ~/.claude/skills/ (or .claude/skills/ inside a project).
3. Start a new session. Claude Code loads the skill when your request matches.

Codex

1. Download the skill .zip.
2. Unzip it into ~/.agents/skills/ (or .agents/skills/ inside a project).
3. Codex picks it up on its own. Type $ and the skill name to use it, or just ask for the task.

Cursor

1. Download the Cursor rule (.mdc).
2. Save it in .cursor/rules/ inside your project.
3. Cursor's agent applies the rule when your request matches its description.

AGENTS.md (Codex, Cursor, and other coding agents)

1. Copy the AGENTS.md section.
2. Paste it into AGENTS.md at the root of your repository, creating the file if needed.
3. Coding agents that read AGENTS.md follow it when your request fits.