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What is Claude Code?

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What is Claude Code?

Claude Code is an agentic coding tool that understands your codebase, edits your files, runs commands, and integrates with your existing developer tools to help you get things done faster. It's available in your terminal, Visual Studio Code, the Claude Desktop app, on the web, and in JetBrains IDEs.

What Separates Claude Code from Claude?

If you've used Claude.ai before, you might be wondering what makes Claude Code different. Unlike Claude.ai, Claude Code has direct access to your files, your terminal, and your entire codebase. Instead of copying and pasting code back and forth, it goes in and does the work itself.

The key differentiator is that Claude Code works as an AI Agent.

What is an Agent?

An AI Agent is software that can interact with its environment and perform actions to complete a defined goal. At its core, this works by having a large language model operating in a loop in real time. AI Agents can have access to tools, external services, or even other AI Agents to help reach their goals.

What Can Claude Code Actually Do?

Here's what that looks like in practice:

  • Read and understand your codebase. You can ask Claude Code to explain a feature or trace a bug throughout your code.
  • Edit files across your project. Claude Code can refactor a function and update every file that references it.
  • Run terminal commands. It can execute your build script, run your tests, install packages, and use the output to decide what to do next.
  • Search the web. If it needs documentation or the latest API references, it can look that up for you.

Using Claude Code Effectively

To use Claude Code effectively, keep these three concepts in mind:

The context window. Think of this as Claude's working memory. It can hold a lot, but not everything at once. This is where the "agentic" aspect comes in — Claude finds strategic ways to locate answers within your codebase without loading the entire thing into context.

It asks for permission. By default, Claude Code will ask you before running commands or making changes. You're always in control, whether you prefer a hands-on or hands-off approach.

It can make mistakes. Just like any tool, Claude Code isn't perfect. It might misunderstand your intent, introduce a bug, or over-engineer a solution. Staying in the loop helps you catch these early.

Recap

Claude Code is an agentic coding tool. It reads your codebase, edits your files, runs commands, and connects to external tools to help you ship faster. You can use it today in your terminal, VS Code, JetBrains, and the Claude Desktop app.

🎬 Video transcript

Source video: fl1DSmwQKKY

📜 Click to expand transcript (cleaned + AI-translated)

Introduction to Claude Code

Claude Code is an agentic coding tool that understands your codebase, edits your files, runs commands, and integrates with your existing developer tools to help you get things done faster. It is available in your terminal, Visual Studio Code, the Claude Desktop app, on the web, and JetBrains IDEs.

Claude Code vs. Claude AI

If you've ever used Claude AI, you're probably wondering what the difference is between the two. Unlike Claude AI, Claude Code has direct access to your files, your terminal, and your entire codebase. Instead of copying and pasting code back and forth, it can go in and do all the work itself.

The easiest differentiator is that Claude Code works as an AI agent. An AI agent is software that can interact with its environment and perform actions to complete a defined goal. The most basic way this can be done is by having a Large Language Model (LLM) in a loop in real-time. AI agents have access to tools, external services, or other AI agents to help them reach their predefined goals.

Key Capabilities

What does that actually look like in practice? Here are a few examples:

  • Codebase Understanding: It can read and understand your codebase. You can ask Claude Code to explain a feature or trace a bug throughout your code.
  • Command Execution: Claude Code can execute your build scripts, run your tests, install packages, and use the output to decide what to do next.
  • Web Search: It can search the web. If it needs documentation on the latest API references, for example, it can do that for you.

Core Concepts for Effective Use

To use Claude Code effectively, it's important to understand these three concepts:

1. Context Window

Think of this as Claude's working memory. It can hold a lot, but not everything at once. This is where the agentic aspect comes in: it uses strategic ways to find answers within your codebase without needing to store the entire codebase into context simultaneously.

2. Permission and Control

By default, Claude Code will ask you for permission before running commands or making changes to your codebase. You are always in control, whether you prefer to be hands-on or more passive.

3. Limitations

Just like any tool, Claude Code isn't perfect. It might misunderstand your intent, introduce a new bug, or over-engineer a solution.

Summary

Claude Code is an agentic coding tool that reads your codebase, edits files, runs commands, and connects to external tools to help you ship faster. It is currently available for use in the terminal, VS Code, JetBrains, and the Claude Desktop app.

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