How Claude Code works - Basics

Claude Code is an agentic coding tool that reads your codebase, edits files, runs commands, and integrates with your development tools. Available in your terminal, IDE, desktop app, and browser.

Claude Code is an AI-powered coding assistant that helps you build features, fix bugs, and automate development tasks. It understands your entire codebase and can work across multiple files and tools to get things done.

Claude Code runs on several surfaces: the terminal, IDE extensions, a desktop app, and the web. Choose one from the tabs below to get started. Most surfaces require a Claude subscription or Anthropic Console account. The Terminal CLI and VS Code also support third-party providers.

Claude Code is an agentic assistant that runs in your terminal. While it excels at coding, it can help with anything you can do from the command line: writing docs, running builds, searching files, researching topics, and more.

The agentic loop

When you give Claude a task, it works through three phases: gather context, take action, and verify results. These phases blend together. Claude uses tools throughout, whether searching files to understand your code, editing to make changes, or running tests to check its work.

The loop adapts to what you ask. A question about your codebase might only need context gathering. A bug fix cycles through all three phases repeatedly. A refactor might involve extensive verification. Claude decides what each step requires based on what it learned from the previous step, chaining dozens of actions together and course-correcting along the way.

You’re part of this loop too. You can interrupt at any point to steer Claude in a different direction, provide additional context, or ask it to try a different approach. Claude works autonomously but stays responsive to your input.

The agentic loop is powered by two components: models that reason and tools that act. Claude Code serves as the agentic harness around Claude: it provides the tools, context management, and execution environment that turn a language model into a capable coding agent.