Basic Usage

After installing Claude Code, learn the essential usage patterns that will make you productive with this AI-powered development assistant.

Quick Answer

Claude Code is most useful when you give it a concrete project goal, point it at the relevant files, ask it to inspect before editing, and verify the result with the project's real commands.

Your task	Prompt pattern	What to verify	Common mistake
Understand a codebase	`Explain how <feature> works. Read the relevant files first.`	Claude names real files and data flow.	Asking for architecture without giving a target feature.
Fix a bug	`Reproduce or inspect <symptom>, identify the cause, then patch it.`	Test, build, or manual check passes.	Asking "fix this" without the error text or file path.
Add a feature	`Plan the change first, then implement the smallest working version.`	The new path works and old behavior still passes.	Letting Claude rewrite unrelated code.
Refactor	`Find the current pattern, propose a scoped refactor, then change only those files.`	Diff is small and tests still pass.	Refactoring before understanding local conventions.
Review code	`Review for bugs and regressions. Prioritize findings with file references.`	Findings are tied to line-level evidence.	Asking for generic best practices.
Write docs	`Update docs to match the current code and commands.`	Commands, paths, and links are real.	Writing docs from memory instead of checking files.

First Session Checklist

Open Claude Code from the project root.
Run /status if billing, account, or API key behavior matters.
Ask Claude to inspect before editing.
Name the files, command, symptom, or feature you care about.
Ask it to run the project's verification command after changes.

Starting a Conversation

Simple Commands

Claude Code works best with clear, specific instructions:

Create a React component for a user profile card

Fix the TypeScript errors in the authentication module

Add unit tests for the shopping cart functionality

Natural Language

You can interact with Claude using natural language:

I'm getting a 404 error when trying to access the /api/users endpoint.
Can you help me debug this issue?

The mobile navigation menu isn't working properly on small screens.
Please help me make it responsive.

Essential Workflows

1. Explore-Plan-Code

This is the most versatile Claude Code pattern:

Step 1: Explore

Help me understand the current authentication system in this codebase

Step 2: Plan

I need to add OAuth login support. What's the best approach for this project?

Step 3: Code

Implement Google OAuth integration using the plan we discussed

2. File Operations

Reading Files

Show me the content of src/components/Header.tsx

Editing Code

Update the Header component to include a dark mode toggle

Creating Files

Create a new utility function for formatting dates in src/utils/date.ts

3. Testing and Quality

Running Tests

Run the test suite and fix any failing tests

Code Quality

Review this component for potential improvements and best practices

Error Fixing

Fix the build errors and make sure the project compiles successfully

Working with Projects

Project Context

Claude automatically understands your project structure:

Add a new API endpoint for user preferences following the existing patterns

Create a component that matches the design system used in other components

Code Style Consistency

Claude maintains consistency with your existing code:

Refactor this function to match the coding style used in the rest of the project

Add TypeScript types following the patterns in the existing codebase

Advanced Usage Patterns

1. Multi-Step Tasks

Break complex tasks into manageable steps:

I need to implement a complete user authentication system.
Let's start by planning the architecture and then implement it step by step.

2. Context Building

Provide relevant context for better results:

I'm working on an e-commerce app using React and Node.js.
The payment system uses Stripe. I need to add subscription billing.
Here's the current payment code: [paste code]

3. Iterative Development

Build features incrementally:

Create a basic user dashboard with just the profile section first.
We'll add analytics and settings in the next iteration.

Good: "Fix the memory leak in the useEffect hook in UserProfile.tsx" Better: "The useEffect in UserProfile.tsx on line 15 is causing a memory leak because it's not cleaning up the event listener"

2. Provide Context

Good: "Add error handling" Better: "Add error handling to the API calls in the user service, following the pattern used in the auth service"

3. Use Examples

Good: "Style this button" Better: "Style this button to match the primary buttons in the design system, like the one in LoginForm.tsx"

4. Reference Existing Code

Create a new component similar to UserCard but for displaying product information

Use the same validation pattern as in the registration form

Common Commands

Development

Start the development server
Build the project for production
Run the linting checks
Update the dependencies

Debugging

Help me debug this error: [error message]
Check why the tests are failing
Investigate the performance issue in [component]

Code Quality

Review this code for security issues
Optimize this function for better performance
Add proper error handling to this API call

Documentation

Add JSDoc comments to this function
Update the README with the new features
Create API documentation for these endpoints

Getting Help

Ask for Explanations

Explain how this authentication middleware works

Request Best Practices

What's the best way to handle state management in this React app?

Troubleshooting

The build is failing with this error: [error]. How do I fix it?

Next Steps

Once you're comfortable with basic usage:

Learn Configuration: Set up CLAUDE.md and tool allowlists
Explore Workflows: Master advanced patterns like test-driven development
Optimize Performance: Learn context management and direction correction
Integrate Tools: Connect with GitHub CLI, databases, and other services

Next: CLAUDE.md configuration - Learn how to customize Claude Code for your workflow.