Claude Code Complete Tutorial

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

irm https://claude.ai/install.ps1 | iex

brew install claude-code

npm install -g @anthropic-ai/claude-code

claude doctor

claude

~/.claude/settings.local.json

your-project/.claude/settings.local.json

your-project/.mcp.json

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/allowed/files"]
    },
    "github": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-github"],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "${GITHUB_TOKEN}"
      }
    }
  },
  "defaultModel": "claude-sonnet-4.5",
  "experimental": {
    "sandboxing": true
  }
}

claude

claude "checkout a new branch and lint this project"

claude -p "analyze this project's dependencies"

# Project Guidelines

This is a web application project.

## Architecture

- Backend: Node.js + Express
- Frontend: React + TypeScript
- Database: PostgreSQL
- Cache: Redis

## Code Conventions

- Use async/await for asynchronous operations
- Follow REST API design principles
- Use ESLint and Prettier for code formatting
- Run tests and lint checks before committing

## Testing

- Unit Tests: Jest
- Integration Tests: Supertest
- Run Tests: npm test
- Coverage Report: npm run coverage

## Common Commands

- Start dev server: npm run dev
- Production build: npm run build
- Database migration: npm run migrate

Please conduct a comprehensive code review:

1. Check for potential security vulnerabilities (SQL injection, XSS, CSRF, etc.)
2. Evaluate code quality and maintainability
3. Check adherence to project coding standards
4. Provide specific improvement suggestions

$ARGUMENTS

/review src/Services/UserService.cs

Analyze performance bottlenecks in the following code and provide optimization solutions:

Focus areas:
- Database query efficiency (N+1 issues, missing indexes)
- Memory usage (memory leaks, unnecessary object allocation)
- Algorithm complexity
- Concurrency handling
- Caching strategy

$ARGUMENTS

# Add stdio-based server
claude mcp add --transport stdio <name> <command> [args...]

# Add HTTP-based server
claude mcp add --transport http --scope local <name> <url>

{
  "mcpServers": {
    "database": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-postgres"],
      "env": {
        "POSTGRES_CONNECTION_STRING": "${DATABASE_URL}"
      }
    },
    "slack": {
      "command": "node",
      "args": ["./mcp-servers/slack-server.js"],
      "env": {
        "SLACK_BOT_TOKEN": "${SLACK_TOKEN}"
      }
    },
    "custom-api": {
      "transport": "http",
      "url": "https://your-mcp-server.com",
      "headers": {
        "Authorization": "Bearer ${API_KEY}"
      }
    }
  }
}

{
  "filesystem": {
    "command": "npx",
    "args": ["-y", "@modelcontextprotocol/server-filesystem", "/allowed/path"]
  }
}

{
  "github": {
    "command": "npx",
    "args": ["-y", "@modelcontextprotocol/server-github"],
    "env": {
      "GITHUB_PERSONAL_ACCESS_TOKEN": "${GITHUB_TOKEN}"
    }
  }
}

{
  "google-drive": {
    "command": "npx",
    "args": ["-y", "@modelcontextprotocol/server-google-drive"],
    "env": {
      "GOOGLE_APPLICATION_CREDENTIALS": "${GOOGLE_CREDS_PATH}"
    }
  }
}

claude "Convert all service methods in src/Services/ directory to async pattern using async/await, ensure proper exception handling"

claude "Generate complete unit tests for UserService.cs using xUnit and Moq, covering all public methods and edge cases"

Generate complete unit tests for the following code:

Test Framework: xUnit
Mock Framework: Moq
Coverage Requirements:
- All public methods
- Normal and exception flows
- Boundary conditions
- Null handling

Test Naming Convention: MethodName_Scenario_ExpectedBehavior

$ARGUMENTS

/generate-tests src/Services/UserService.cs

claude "Create a complete user management API including CRUD operations, using Minimal APIs, following project's ResponseWrapper pattern, add JWT authentication, include input validation"

claude "Add EmailVerified and EmailVerificationToken fields to User entity, create migration and apply to database"

claude "Analyze database queries in OrderService.cs, identify N+1 issues, optimize query performance using Include and ThenInclude"

claude "Create new branch feature/user-email-verification, commit current changes, push to remote, and create PR"

claude "Rename UserRepository to UserDataRepository, update all references including interfaces, implementations, and dependency injection configuration"

claude "Scan all service classes in Services directory, add corresponding AddScoped registrations in Program.cs"

claude "Add detailed Serilog structured logging to PaymentService.cs, including method entry/exit, parameters, execution time, and exceptions"

claude "Create multi-stage Dockerfile for building .NET API application, create docker-compose.yml including API, PostgreSQL, Redis, and RabbitMQ"

claude --dangerously-skip-permissions "fix all ESLint errors"

# Monitor logs and notify on anomalies
tail -f app.log | claude -p "if you see any anomalies, notify me via Slack"

# Analyze test failure reasons
dotnet test | claude -p "analyze failed tests and suggest fixes"

claude "Replace all var declarations with explicit type declarations in src/**/*.cs"

#!/bin/bash
claude -p "review staged changes, check for security vulnerabilities and code quality issues" --dangerously-skip-permissions

# Monitor performance metrics
claude "monitor app.log, if response time exceeds 500ms analyze and suggest optimizations" &

# Monitor error rate
claude "monitor error logs, aggregate common errors and generate daily report" &

Create new service in src/Services/ directory:

Service Name: $ARGUMENTS

Include:
1. Interface definition (I$ArgumentsService)
2. Implementation class ($ArgumentsService)
3. Unit test file ($ArgumentsServiceTests)
4. Service registration in Program.cs

Follow project's Repository Pattern and dependency injection conventions.

/scaffold-service Payment

claude "scan src/ directory, generate API documentation (Markdown format) including all public endpoints, request/response formats, and usage examples"

claude "check outdated dependencies in package.json, update each to latest stable version one by one, run tests to ensure no breaking changes"

{
  "experimental": {
    "sandboxing": true
  }
}

name: Claude Code Review

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  review:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3

      - name: Install Claude Code
        run: curl -fsSL https://claude.ai/install.sh | bash

      - name: Run Code Review
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
        run: |
          claude -p "review PR changes, check for security vulnerabilities, code quality, and best practices" > review.md

      - name: Post Review Comment
        uses: actions/github-script@v6
        with:
          script: |
            const fs = require('fs');
            const review = fs.readFileSync('review.md', 'utf8');
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: review
            });

name: Auto Fix Lint Errors

on:
  push:
    branches: [develop]

jobs:
  auto-fix:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3

      - name: Install Claude Code
        run: curl -fsSL https://claude.ai/install.sh | bash

      - name: Fix Lint Errors
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
        run: |
          claude --dangerously-skip-permissions "fix all ESLint errors"

      - name: Commit Changes
        run: |
          git config user.name "Claude Code Bot"
          git config user.email "bot@example.com"
          git add .
          git commit -m "chore: auto-fix lint errors" || echo "No changes"
          git push

# Clear existing credentials and re-authenticate
rm -rf ~/.claude/auth
claude

# Check MCP server configuration
claude mcp list

# Test specific server
claude mcp test <server-name>

# System health check
claude doctor

# View configuration
claude config list

# View logs
tail -f ~/.claude/logs/claude.log

# Clear cache
rm -rf ~/.claude/cache

ANTHROPIC_BASE_URL=https://routin.ai/
ANTHROPIC_API_KEY=your-meteor-platform-api-key

{
  "apiEndpoint": "https://routin.ai/",
  "apiKey": "${ANTHROPIC_API_KEY}"
}

# Test connection
claude -p "hello world"