Everything Claude Code: The Complete Guide

Claude Code is Anthropic's agentic coding tool that lives in your terminal. Instead of autocompleting inside an editor, it reads your codebase, plans multi-step changes, edits files, runs commands, and iterates — the way a pair programmer would. This guide is the single place to understand what it is and how to get the most from it, with links out to deeper pieces on each topic.

What Is Claude Code?

Claude Code is a command-line agent powered by Anthropic's Claude models. You run it in your project directory, describe what you want in plain English, and it does the work — searching files, writing code, running tests, and fixing what it broke. The key difference from IDE-based tools like Cursor is that Claude Code is terminal-first and agentic: it's built to take on whole tasks, not just suggest the next line.

It works with any language, any editor (it edits the files on disk, so your editor just sees the changes), and integrates with git, GitHub, and external tools via MCP.

Installing Claude Code

Install it globally, then run it inside any project:

npm install -g @anthropic-ai/claude-code
cd your-project
claude

On first run it walks you through authentication. From there, everything happens in the interactive session — you type requests, approve or reject actions, and watch it work.

The CLI and Interactive Session

Everything centers on the interactive session. You can:

• Ask for a change and watch it edit files
• Approve or deny each action (in default mode) or let it run (auto-accept)
• Reference files with @, run slash commands, and interrupt mid-task
• Pipe it a prompt non-interactively (claude -p "...") for scripting

The interactive nature is what makes it feel less like autocomplete and more like delegation.

Plan Mode

For anything non-trivial, Plan Mode is the feature to know. Press Shift+Tab to cycle into it, and Claude researches your code and proposes a plan before editing anything — so you catch a wrong approach before any code changes. It's the highest-leverage habit for big or unfamiliar tasks.

→ Full walkthrough: Claude Code Plan Mode

Skills and Extensibility

Claude Code is extensible in several ways:

• Skills — packaged instructions for recurring, specialized workflows that load only when relevant
• MCP (Model Context Protocol) — connect external tools and data sources (databases, issue trackers, docs)
• Hooks — run your own commands automatically at points in the agent's lifecycle
• Subagents — spin up focused agents for parallel or specialized work

This is what lets teams shape Claude Code around their own stack instead of adapting to it.

GitHub Integration

Claude Code works naturally with git and GitHub: it can create branches, write commits, open pull requests, and (via the GitHub app) respond to PR comments. For teams, that means it fits into existing review workflows instead of sitting beside them.

Pricing

Claude Code is available through Anthropic's Claude subscription plans and via API usage-based billing. Which makes sense depends on how heavily you use it — subscription for steady daily use, API for occasional or programmatic use. (Check Anthropic's current pricing page for exact tiers, as they change.)

→ Deeper dive: Claude Code Pricing

How It Compares

• Claude Code vs Cursor — terminal agent vs AI-native IDE. The biggest workflow decision.
• Claude Code vs Codex — the two leading agentic CLI coding tools, head to head.

Both Windsurf and Codeium occupy adjacent space; see the full AI coding tools directory to compare across the field.

Who Claude Code Is For

It shines for developers who are comfortable in the terminal and want to delegate whole tasks — refactors, migrations, bug hunts, feature scaffolding — rather than nudge autocomplete. If you live in an IDE and want inline suggestions, an editor-based tool may fit better; if you want an agent that takes the wheel and reports back, Claude Code is the strongest option in its class.

FAQ

Is Claude Code free? No — it needs a Claude subscription or API access. There's no permanent free tier, though plans vary.

Does it work with my editor? Yes — it edits files on disk, so any editor picks up the changes. It doesn't replace your editor; it works alongside it.

Can it run commands and tests? Yes — it can run your build, tests, and other commands, then act on the results. You control the permission level.

Terminal or IDE? Terminal. If you specifically want an in-editor experience, compare with Cursor.

Start with Plan Mode if you're new — it's the fastest way to trust the agent on real work. Then browse the full AI coding tools directory to see where Claude Code fits.