Level 5Lesson 38⏱️ 60 min

AI Tools for Devs - The Landscape

GitHub Copilot, Claude Code, Cursor, Windsurf - what they each do, how to choose, and how to set them up.

The AI Coding Tool Explosion

In 2024-2025, AI coding tools went from novelty to necessity. Every major IDE now has AI built in or available via extension. The challenge is no longer "should I use AI?" - it's "which tool for which job?"

The main players:
  • GitHub Copilot - Microsoft/GitHub. Deep VS Code + JetBrains integration. Powered by OpenAI models. Best for inline completion.
  • Claude Code - Anthropic. Terminal-first, full-codebase awareness. Best for large refactors, multi-file changes, and agentic tasks.
  • Cursor - Fork of VS Code. Deep file indexing, Cmd+K edits, Composer for multi-file. Best all-in-one IDE experience.
  • Windsurf - Codeium's IDE. "Flows" for agentic multi-step changes. Fast and lightweight.
  • Codeium / Supermaven - Free alternatives for inline completion. Good for teams on a budget.

How These Tools Actually Work

All AI coding tools share the same underlying mechanism - they send context to a language model and stream back completions. Understanding what context they send is the key to using them well.

What the model typically sees:
┌─────────────────────────────────────┐
│  System prompt (tool's instructions) │
│  Current file content               │
│  Cursor position / selected code    │
│  Nearby open files (sometimes)      │
│  Recent edits / diff (sometimes)    │
│  Your chat history (chat mode)      │
│  Codebase index (Cursor, Claude Code)│
└─────────────────────────────────────┘

The model CANNOT see:
- Files you haven't opened/shared
- Your local env variables (unless you paste them)
- Runtime state / memory at execution time
- Other projects or repos

Tool Comparison at a Glance

Tool          | Best For              | IDE          | Cost/mo
--------------|----------------------|--------------|--------
GitHub Copilot| Inline completion    | VS Code,     | $10-19
              | PR summaries         | JetBrains    |
Claude Code   | Large refactors,     | Terminal /   | API usage
              | full-repo awareness  | any IDE      |
Cursor        | All-in-one AI IDE    | Own IDE      | $20
              | multi-file edits     | (VS Code UX) |
Windsurf      | Agentic flows        | Own IDE      | Free/Pro
              | Fast completions     | (VS Code UX) |
Codeium       | Free completion      | VS Code,     | Free
              | budget teams         | JetBrains    |

Setting Up GitHub Copilot in VS Code

1
Install GitHub Copilot + GitHub Copilot Chat extensions from VS Code marketplace
2
Sign in with your GitHub account (requires Copilot subscription - free tier available for students/OSS maintainers)
3
Enable inline suggestions: Settings → GitHub Copilot → Enable
4
Open Copilot Chat with Ctrl+Alt+I (Windows) or Cmd+Shift+I (Mac)
5
Test: open a new file, type a function signature, and wait 1-2s for ghost text

Setting Up Claude Code

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

# Set your API key
export ANTHROPIC_API_KEY="sk-ant-..."

# Add to shell profile so it persists
echo 'export ANTHROPIC_API_KEY="sk-ant-..."' >> ~/.zshrc

# Run in your project
cd my-project
claude

# First thing to do: let Claude read your codebase
> /init
# This creates a CLAUDE.md with project context
Claude Code vs the others: Claude Code is terminal-first and sees your entire repo (not just open files). It's uniquely powerful for "make this architectural change across 20 files" tasks that other tools handle poorly.

Choosing Your Stack

Recommended combinations:
  • Solo developer: Cursor (all-in-one) + Claude Code for big refactors
  • Team on VS Code: GitHub Copilot (shared licenses) + Claude Code for heavy lifting
  • Budget-conscious: Codeium (free inline) + Claude Code (pay per use)
  • Enterprise / security-sensitive: GitHub Copilot Enterprise (data stays in org) + Claude Code with IP allow-listing
Lesson 38 Quick Reference
GitHub Copilot

Best inline completion, deep VS Code/JetBrains integration, $10-19/mo

Claude Code

Terminal-first, full-repo awareness, best for large multi-file changes

Cursor

AI-native VS Code fork, Cmd+K edits, Composer for multi-file, $20/mo

Windsurf

Codeium IDE with agentic Flows, fast and lightweight

Context window

What the model sees: current file + cursor + open files + index

/init

Claude Code command to read your repo and create CLAUDE.md project context

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