codebase-onboarding

# Codebase Onboarding

**Tier:** POWERFUL  
**Category:** Engineering  
**Domain:** Documentation / Developer Experience  

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## Overview

Analyze a codebase and generate comprehensive onboarding documentation tailored to your audience. Produces architecture overviews, key file maps, local setup guides, common task runbooks, debugging guides, and contribution guidelines. Outputs to Markdown, Notion, or Confluence.

## Core Capabilities

- **Architecture overview** — tech stack, system boundaries, data flow diagrams
- **Key file map** — what's important and why, with annotations
- **Local setup guide** — step-by-step from clone to running tests
- **Common developer tasks** — how to add a route, run migrations, create a component
- **Debugging guide** — common errors, log locations, useful queries
- **Contribution guidelines** — branch strategy, PR process, code style
- **Audience-aware output** — junior, senior, or contractor mode

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## When to Use

- Onboarding a new team member or contractor
- After a major refactor that made existing docs stale
- Before open-sourcing a project
- Creating a team wiki page for a service
- Self-documenting before a long vacation

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## Codebase Analysis Commands

Run these before generating docs to gather facts:

```bash
# Project overview
cat package.json | jq '{name, version, scripts, dependencies: (.dependencies | keys), devDependencies: (.devDependencies | keys)}'

# Directory structure (top 2 levels)
find . -maxdepth 2 -not -path '*/node_modules/*' -not -path '*/.git/*' -not -path '*/.next/*' | sort | head -60

# Largest files (often core modules)
find src/ -name "*.ts" -not -path "*/test*" -exec wc -l {} + | sort -rn | head -20

# All routes (Next.js App Router)
find app/ -name "route.ts" -o -name "page.tsx" | sort

# All routes (Express)
grep -rn "router\.\(get\|post\|put\|patch\|delete\)" src/routes/ --include="*.ts"

# Recent major changes
git log --oneline --since="90 days ago" | grep -E "feat|refactor|breaking"

#...