How to Use Claude Code: A Beginner's Guide for Developers

Claude Code is Anthropic's terminal-based coding agent — it reads your actual codebase, runs commands, edits files, and can carry out multi-step tasks, rather than just answering questions in a chat window. Here's how to actually get productive with it.

Installing and First Run

npm install -g @anthropic-ai/claude-code
claude

Run it from inside your project's root directory — Claude Code reads your actual files and project structure, so context matters from the very first command.

The CLAUDE.md File

This is the single highest-leverage thing you can set up. A CLAUDE.md file in your project root gives Claude Code persistent context about your codebase — tech stack, coding conventions, commands to run tests, things to never do:

# CLAUDE.md
## Tech Stack
- Laravel 12, MySQL, Blade templates

## Commands
- Test: `php artisan test`
- Lint: `./vendor/bin/pint`

## Rules
- Never edit migrations that have already run in production
- Always run tests before considering a task done

Claude Code reads this automatically every session — you're not repeating the same instructions in every conversation.

What It's Actually Good At

• Multi-file refactors ("rename this function everywhere it's used")
• Writing and running tests, then fixing what fails
• Reading an error message, finding the actual cause, and fixing it — not just guessing
• Explaining an unfamiliar codebase by actually reading it

Working With It, Not Against It

Give it real, specific tasks with enough context, and let it work — checking in on genuinely ambiguous decisions rather than every small step. Review its diffs before accepting large changes, same as you would with a junior developer's pull request.

Permission Modes

Claude Code asks before running commands or editing files by default. For a task you trust it with fully, you can grant broader permissions for that session — but start cautious, especially with anything that touches git history or deletes files.

The learning curve is mostly about writing clear tasks and trusting it with appropriately-sized chunks of work — not learning special commands.