Introduction to Claude Code

Learn what Claude Code is, how it compares to competitors, and how to use it through QCode.cc

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Claude Code is Anthropic's official CLI (Command Line Interface) agentic coding assistant. Since its general availability in May 2025, it has become a critical tool for world's leading enterprises, including Netflix, Spotify, KPMG, L'Oreal, and Salesforce. In just 6 months, Claude Code reached the milestone of $1 billion in annual run-rate revenue.

What is Claude Code?¶

Claude Code is not a traditional code completion tool—it's a true Agentic Coding Assistant. It works like an experienced developer, autonomously understanding, planning, and executing complex programming tasks.

Core Capabilities¶

• Autonomous Planning: Understands complex tasks and creates execution plans without step-by-step guidance

• Code Operations: Directly reads, edits, and creates any files in your project

• Terminal Execution: Runs tests, installs dependencies, executes builds, and more

• Deep Context Understanding: 200K token context window, expandable to 1M tokens for comprehensive codebase awareness

• Subagent Collaboration: Spawns specialized subagents to handle specific tasks efficiently

Major 2025 Updates¶

• Plan Mode: Analyze and research first, then create implementation plans to reduce errors

• Subagents: Background agents for code review, testing, and specialized tasks

• CLAUDE.md Memory System: Project-level config files that remember your preferences and standards

• MCP Extension Protocol: Connect external tools and services via Model Context Protocol

• Opus 4.8 / 4.7 Model: The latest and most powerful coding model (4.8 is current flagship), significantly improved code generation

Comparison with Competitors¶

Claude Code vs OpenAI Codex CLI¶

Verdict: Claude Code excels in code quality, interaction experience, and intent understanding; with the 1M context option, it also matches Codex on context window size.

QCode.cc also supports Codex! Claude Code and Codex use the same QCode key, so you can freely choose which tool to use. See Codex Integration to learn how to configure it.

Claude Code vs Google Gemini CLI¶

Verdict: Gemini CLI’s Pro/consumer tiers stopped on 2026-06-18; the successor is Antigravity CLI. On capability, Gemini CLI has a huge context window but is weaker at coding than Claude Code — still not the pick for professional development. Enterprise paid keys can keep using Gemini CLI.

Note: Gemini CLI stopped serving Pro/consumer accounts on 2026-06-18 (Google announcement); the successor is Google Antigravity CLI. Enterprise paid keys are unaffected. QCode does not offer Gemini models for now.

Why Claude Code is the Best Choice¶

1. Highest Code Quality: Claude models consistently lead in programming benchmarks

2. Best Developer Experience: Detailed explanations, clear planning, precise intent understanding

3. Enterprise Validated: The tool of choice for Netflix, Spotify, and other top enterprises

4. Rapid Iteration: 176 updates shipped in 2025, continuously evolving

Why Choose QCode.cc?¶

Claude Code is powerful, but official pricing is steep:

• Anthropic Max Subscription: $200/month

• API Pay-per-use: Opus 4.8 / 4.7 $5/$25 per million tokens (input/output, same price)

QCode.cc Advantages¶

Through QCode.cc, you get the same Claude Code functionality. Billed per token; per-model rates are listed on qcode.cc/models:

Service Guarantees¶

• Asia-Pacific Optimized: Korea / Taiwan / Hong Kong nodes for access from Asia, plus a US node (us.qcode.cc, Los Angeles) for North America / Europe

• Seamless Migration: API compatible, just change environment variables

• Account Protection: Issues are handled promptly

Quick Start¶

Choose a plan and get your key¶

First pick an option in How to Choose a Plan (personal plan, Pay-as-you-go Packs, Enterprise Team or Partner), then get your cr_ key in the Dashboard. Whichever option you choose, the key is used the same way and the steps below are identical.

Install Claude Code¶

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

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

Configure QCode.cc¶

export ANTHROPIC_BASE_URL="https://api.qcode.cc/api"
export ANTHROPIC_AUTH_TOKEN="your-api-key"

Start Using¶

cd your-project
claude

Then you can communicate with Claude Code in natural language:

> Analyze this project's architecture and find areas for optimization
> Write comprehensive unit tests for the UserService
> Refactor src/utils.js to improve code readability

System Requirements¶

• OS: Windows 10+, macOS 10.15+, Linux

• Node.js: 18.0 or above (22 LTS recommended)

• Network: Stable internet connection

Next Steps¶

Ready to experience the most powerful AI coding assistant?

1. Choose a plan and get your key first

2. Check out the Installation Guide to complete setup

3. Read Quick Start to learn basic usage

4. Explore Usage Tips to boost your productivity

5. Planning to run agents on an overseas server? See Cloud Servers: Picking, Buying and Using

Enterprise →