What is Claude Code?

Sat, 03 Oct 2026 00:00:00 +0000

What Separates Claude Code from Claude?

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 goal

What Can Claude Code Do?

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

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.
You control its permissions.
- Claude Code’s permission modes let you choose how hands-on to be: it can ask you before running commands or making changes, or run in auto mode, where a background safety check screens each action instead.
- 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.

How Claude Code works

Sat, 03 Oct 2026 00:00:00 +0000

Claude Code combines several agentic concepts: an agentic loop, a managed context window, tools, and configurable permissions — all inside your terminal. It can read your codebase, take action, and verify its own work.

The Agentic Loop

Claude Code is best explained through the agentic loop:

You enter a prompt into Claude Code.
Claude gathers the context it needs by interacting with the model, which returns text or a tool call that Claude Code can execute.
It takes action — for example, editing a file or running a command.
It verifies the results and determines whether they achieve what your prompt set out to do.
If they do, Claude finishes and waits for the next prompt. If they don’t, it loops back and tries again until the results are complete and verifiable.

Throughout this loop, you can add context, interrupt, or steer the model to help guide it toward your goal.

Context

Claude has a context window that determines how much of your conversation, file contents, command outputs, and more it can store and reference.

Once you reach that limit, Claude Code compacts your conversation — automatically determining what it can remove or summarize to bring the context window back down to a usable size.

Tools

Tools are the backbone of how agents work.

Tools let Claude Code determine when to execute code to get closer to completing a task. This could be a file-reading tool, a web search tool, or any number of other capabilities.
Claude Code uses semantic understanding to determine when to call a tool and how to use the output.

Permissions

Claude Code has several permission modes:

Manual: Claude asks for explicit permission before editing a file or running a shell command.
Auto-accept: Files are edited without asking, but commands still require approval.
Plan mode: Uses read-only tools to compile a plan of action before starting any work.
Auto mode: Claude works without permission prompts while a classifier checks each action in the background, targeted at blocking actions that are irreversible, destructive, or aimed outside your environment. When something is blocked, Claude usually finds a safer approach or asks you for the go-ahead.

Caution

Be cautious when skipping permissions — giving Claude Code free rein to run commands means a mistake could be harder to catch before it happens.

What is Claude Code? |

What is Claude Code?

What Separates Claude Code from Claude?

What is an Agent?

What Can Claude Code Do?

Using Claude Code Effectively

How Claude Code works

The Agentic Loop

Context

Tools

Permissions