Install Claude Code — requires Node.js 18+

curl -fsSL https://claude.ai/install.sh | bash

Navigate to your project and launch:

cd your-project
claude
/init

/init scans your codebase and creates a starter memory file automatically.

CLAUDE.md = Claude’s persistent memory. Loaded automatically at the start of every session.

# Project: MyApp
FastAPI REST + React SPA + Postgres
## Commands
npm run dev / test / lint
## Architecture
/app -> Next.js pages
/lib -> shared utilities
/prisma -> DB schema

Multiple CLAUDE.md files stack at different levels — deeper files add context without overwriting the parent.

• Run /init first, then refine the output
• Be specific — vague prompts get vague results
• Add gotchas Claude cannot infer from the code
• Reference docs with @filename
• Add workflow rules so Claude follows your process
• Keep memory concise — remove outdated notes
• Commit CLAUDE.md to Git for team sharing

Skills = markdown guides Claude auto-invokes via natural language. The description field is critical for auto-activation.

Start with these — each becomes a markdown file Claude learns to invoke automatically.

Hooks = deterministic callbacks — run automatically before or after Claude uses a tool.

"hooks": {
  "PreToolUse": [{
    "matcher": "Bash",
    "hooks": [{
      "type": "command",
      "command": "scripts/sec.sh",
      "timeout": 5
    }]
  }]
}

Control exactly what Claude is and isn’t allowed to do using a permissions block in your settings file.

{
  "permissions": {
    "allow": [
      "Read:*",
      "Bash:git:*",
      "Write:*:*.md"
    ],
    "deny": [
      "Read:env:*",
      "Bash:sudo:*"
    ]
  }
}

Allows: reading files, git, writing Markdown. Blocks: env variables and admin commands.