Claude Code Cheat Sheet: Commands, Config, and Shortcuts

Every CLI flag, slash command, keyboard shortcut, config key, hook event, and environment variable in one place. For deep explanations, see the full Claude Code guide. For first-time setup, see the quickstart.

1. Installation

Three installation methods, in order of preference.

# Native binary (recommended)
curl -fsSL https://claude.ai/install.sh | bash

# Homebrew (macOS)
brew install --cask claude-code

# NPM (deprecated — migrate with `claude install`)
npm install -g @anthropic-ai/claude-code

Install a specific version:

curl -fsSL https://claude.ai/install.sh | bash -s 1.0.58

Verify installation:

claude doctor

Authenticate:

claude auth login       # Log in or switch accounts
claude auth status      # Check current auth state
claude auth logout      # Clear stored credentials

2. CLI Flags

3. Slash Commands

Custom commands: Create .claude/commands/my-command.md (project) or ~/.claude/commands/my-command.md (personal) and invoke with /my-command. Commands support YAML frontmatter for description, allowed tools, model override, and argument interpolation via $ARGUMENTS or positional $1, $2.

---
description: Fix a GitHub issue
allowed-tools: Read, Edit, Bash(git:*)
model: opus
argument-hint: [issue-number]
---

Fix GitHub issue #$ARGUMENTS following our coding standards.

Usage: /fix-issue 123

4. Keyboard Shortcuts

General Controls

Quick Prefixes

Multiline Input

Keybindings are customizable via /keybindings (stored in ~/.claude/keybindings.json).

5. Configuration Files

Precedence Hierarchy (highest to lowest)

First match wins. Enterprise settings cannot be bypassed.

6. Settings.json Reference

Key settings with types and examples. Place in any settings file from the hierarchy above.

{
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "model": "claude-sonnet-4-6",
  "permissions": {
    "allow": ["Read", "Glob", "Grep", "Bash(npm run:*)", "Bash(git:*)", "Edit(src/**)"],
    "deny": ["Read(.env*)", "Bash(rm -rf:*)", "Bash(sudo:*)"],
    "ask": ["WebFetch", "Bash(docker:*)"],
    "defaultMode": "acceptEdits",
    "additionalDirectories": ["../shared-lib"]
  },
  "env": {
    "NODE_ENV": "development"
  },
  "hooks": {},
  "sandbox": {
    "enabled": false,
    "autoAllowBashIfSandboxed": true
  },
  "includeCoAuthoredBy": true,
  "cleanupPeriodDays": 30,
  "respectGitignore": true,
  "showTurnDuration": true,
  "language": "en",
  "autoMemoryDirectory": ".claude/memory",
  "plansDirectory": ".claude/plans"
}

Permission rule syntax: Tool(pattern:*) provides prefix matching. Bash(npm run test:*) allows npm run test, npm run test:unit, etc. File patterns use glob syntax: Edit(src/**).

For the complete settings schema, see the Configuration Deep Dive in the full guide.

7. CLAUDE.md Quick Reference

CLAUDE.md is your project’s instruction file. Claude reads it at the start of every session.

Where it lives:

What to include:

# Project Name

## Stack
- Backend: FastAPI, Python 3.11+
- Frontend: HTMX + Alpine.js + Bootstrap 5

## Commands
- Dev: `uvicorn app.main:app --reload --port 8000`
- Test: `python -m pytest -v`
- Lint: `ruff check .`

## Conventions
- Conventional commits: feat:, fix:, docs:, refactor:
- Never force push to main
- Always activate venv before Python commands

## Key Files
- app/main.py — FastAPI app and routes
- app/models.py — SQLAlchemy models

Keep it scannable. Dense prose wastes context tokens every session. Use bullet points, tables, and short code blocks. Avoid long paragraphs — Claude reads CLAUDE.md at the start of every session, so every word costs context.

Pro tips: - Use # prefix in the REPL to add things to auto-memory without editing CLAUDE.md: # Always use TypeScript strict mode - CLAUDE.md in subdirectories is loaded when Claude reads files in that directory - Team-shared rules go in .claude/rules/*.md for modular organization

8. Permission Modes

Auto Mode (v2.1.85+) is the recommended replacement for --dangerously-skip-permissions. Read-only and file edits are auto-approved. Custom allow/deny rules resolve first. Everything else goes to the safety classifier. Auto-blocked by default: curl | bash, force-push to main, production deploys, mass cloud deletions, IAM changes, sending sensitive data externally.¹

Circuit breaker: 3 consecutive blocks or 20 total in a session pauses back to manual prompting.

# Enable at startup
claude --enable-auto-mode

# Cycle during session
Shift+Tab    # default -> acceptEdits -> auto -> plan

9. Hook Events

For the full hook protocol (input/output JSON, matchers, exit codes), see Hooks Deep Dive in the full guide.

10. Hook Configuration

Hooks live in settings.json or a dedicated hooks.json. Minimal example:

{
  "hooks": {
    "PostToolUse": [
      {
        "matcher": "Edit|Write",
        "hooks": [
          {
            "type": "command",
            "command": "npx prettier --write \"$FILE_PATH\""
          }
        ]
      }
    ],
    "PreToolUse": [
      {
        "matcher": "Bash",
        "hooks": [
          {
            "type": "command",
            "command": ".claude/hooks/validate-bash.sh"
          }
        ]
      }
    ]
  }
}

Matcher syntax:

Exit codes:

Async hooks run in the background without blocking: add "async": true to the hook object.²

11. MCP Quick Setup

Add an MCP server in one command:

# Remote HTTP server (recommended)
claude mcp add --transport http github https://api.githubcopilot.com/mcp/

# Remote with auth header
claude mcp add --transport http api https://api.example.com/mcp \
  --header "Authorization: Bearer $TOKEN"

# Local stdio server
claude mcp add --transport stdio postgres \
  --env "DATABASE_URL=postgresql://user:pass@localhost/db" \
  -- npx -y @anthropic-ai/mcp-server-postgres

Scope control:

claude mcp add --scope project ...   # Team-shared (.mcp.json)
claude mcp add --scope user ...      # Personal (~/.claude.json)

Project .mcp.json example:

{
  "mcpServers": {
    "github": {
      "type": "http",
      "url": "https://api.githubcopilot.com/mcp/"
    },
    "database": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@anthropic-ai/mcp-server-postgres"],
      "env": {
        "DATABASE_URL": "postgresql://user:pass@localhost/db"
      }
    }
  }
}

MCP now has 100 million monthly downloads and 3,000+ indexed servers.³ For transport types, elicitation, and tool search configuration, see the MCP section in the full guide.

12. Subagent Types

Claude automatically delegates to subagents. You can also request them explicitly:

> Use the explore agent to find all auth-related files
> Have a subagent analyze the database schema

Custom subagents are defined in .claude/agents/ (project) or ~/.claude/agents/ (personal) as markdown files with YAML frontmatter. Up to 10 subagents can run in parallel.⁴

Custom agent frontmatter fields:

Example custom agent (.claude/agents/security-reviewer.md):

---
name: security-reviewer
description: Expert security code reviewer. Use PROACTIVELY after code changes to auth or data handling.
tools: Read, Grep, Glob, Bash
model: opus
permissionMode: plan
---

You are a senior security engineer. Analyze for OWASP Top 10 vulnerabilities,
secrets, hardcoded credentials, and SQL injection. Report findings with severity
levels and remediation steps.

13. Environment Variables

Authentication and API

Model Configuration

Cloud Providers

Behavior Control

Tool Configuration

Network and Proxy

For the complete list, see Environment Variables in the full guide.

14. Cost Reference

Pricing per 1 million tokens (as of March 2026).⁵

A typical session consumes 50K-200K input tokens and 10K-50K output tokens. Haiku session: $0.10-$0.45. Opus session: $0.50-$2.25.

The 1M context window is enabled by default for Max, Team, and Enterprise plans (no [1m] suffix required). API-only billing still incurs the long-context surcharge above 200K input tokens.

Switch models during a session:

/model opus       # Switch to Opus 4.6
/model sonnet     # Switch to Sonnet 4.6
/model haiku      # Switch to Haiku 4.5

Decision rule: Simple exploration goes to Haiku. Daily coding goes to Sonnet. Hard reasoning, architecture, and security analysis go to Opus. Use opusplan for complex refactoring (Opus plans, Sonnet executes).

15. Key File Locations

16. Changelog

17. References

This cheat sheet is the quick-lookup companion to the full Claude Code CLI guide. For setup walkthroughs, see the Claude Code quickstart. Last updated March 28, 2026.