⌨️Claude Code Essential Commands

Master the core commands and interactive features

Essential Claude Code Commands

Starting a Session

Terminal
# Start interactive mode in current directory
claude

# Ask a one-off question
claude "explain what this project does"

# Start with a specific prompt
claude -p "analyze this codebase for security issues"

In-Session Slash Commands

When you're inside a Claude Code session, these commands are available:

Command	What It Does
`/help`	Show available commands
`/clear`	Clear conversation history
`/compact`	Summarize conversation to save context
`/cost`	Show token usage and cost
`/doctor`	Check health of your setup
`/init`	Create a CLAUDE.md for your project
`/memory`	View saved memories
`/review`	Review code changes
`/fast`	Toggle fast mode

Common Workflows

Explore a codebase:

Terminal
claude "explain the architecture of this project"
claude "what does the main entry point do?"
claude "find where user authentication is handled"

Write code:

Terminal
claude "add a login page with email and password fields"
claude "write unit tests for the auth module"
claude "create a REST API endpoint for user profiles"

Fix bugs:

Terminal

claude "fix the TypeError in src/utils/parser.ts"
claude "this test is failing: [paste error]. fix it"

Git operations:

Terminal
claude "commit my changes with a descriptive message"
claude "create a new branch called feature/login"
claude "open a PR for my current changes"

Piping Data to Claude

Claude Code follows Unix philosophy — you can pipe data into it:

Terminal
# Analyze logs
tail -200 app.log | claude -p "find any errors or anomalies"

# Review changed files
git diff main --name-only | claude -p "review these changes for issues"

# Process a file
cat data.csv | claude -p "summarize this data"

Non-Interactive Mode

For scripts and automation, use the -p flag (pipe/print mode):

Terminal
# Get a quick answer
claude -p "what is the main export of src/index.ts?"

# Generate code to stdout
claude -p "write a dockerfile for a node app" > Dockerfile

Keyboard Shortcuts

Shortcut	Action
`Enter`	Send message
`Escape`	Cancel current generation
`Ctrl+C`	Exit Claude Code
`Tab`	Accept suggestion
`Up Arrow`	Previous message

Next up: Learn about CLAUDE.md — the file that teaches Claude about your project.

Module 4

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📥 Installing Claude Code

Claude Code in VS Code 💎

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