The "AI Coding" landscape is fragmenting. We essentially have three categories of tools:
The Editor (IDE) Fork: VS Code forks with deep AI integration (Cursor, Windsurf).
The CLI Agent: Autonomous terminal agents (Claude Code, Aider, Goose).
The Chatbot: The classic web interface (ChatGPT, Claude.ai).
Understanding when to use which is the hallmark of a senior engineer.
1. The Editor: Deep Flow State
Tools: Cursor, Windsurf.
These tools are best for "In-Flow" Modification. You are looking at a file, you know what you want to change, and you want AI to speed up the keystrokes.
Best For:
Refactoring a single function.
Writing boilerplate (handlers, types).
Debugging a specific error you see in the editor.
The Killer Feature:Tab-Complete (Copilot++). It predicts your next edit based on your recent cursor movements.
Cursor vs. Windsurf
Cursor: The current market leader. Extremely fast "Apply" (diff) logic. Strong multi-file edit capabilities via "Composer".
Windsurf: Focuses on "Deep Context". It indexes your codebase more aggressively to understand "Flows" (how function A affects function B) better than Cursor, but sometimes feels heavier.
2. The CLI Agent: Fire and Forget
Tools:claude-code, aider, goose.
These tools are best for "Out-of-Loop" Tasks. You want to delegate a task that takes 5-10 minutes, and you don't want to stare at the screen.
Best For:
"Add a unit test suite for this module."
"Upgrade this dependency and fix all breaking changes."
"Lint the entire project and fix errors."
The Workflow:
$ claude "Run the tests, fix any failures, and commit the changes."
You go get coffee. The agent runs the shell commands, sees the failure, edits the file, re-runs the test, and commits.
3. The Chatbot: The Architect
Tools: Claude.ai, ChatGPT (o1/Pro).
These tools are best for "High-Level" Reasoning. When you are stuck on design, not implementation.
Best For:
"Design a SQL schema for a multi-tenant SaaS."
"Critique this architectural proposal."
"Explain how OAuth2 PKCE works."
Why not use the IDE? The IDE is often distracted by the specific file context. The web interface allows you to start "Fresh" and focus purely on abstract concepts.
The Optimal Workflow
Brainstorm in Claude.ai (Web) to get the architecture right.
Scaffold the core structure using Claude Code (CLI) or Cursor Composer.
Refine and polish specific files using Cursor (Editor) with Tab-Complete.
Test/Fix utilizing Claude Code (CLI) to run the test loop while you document.
Summary
Don't marry one tool. Use the CLI for grunt work, the Editor for surgical work, and the Web Chat for brain work.