Three AI coding agents that actually write code for you

GitHub Copilot with GPT-5.6, Cursor, and Windsurf are AI agents that read entire codebases, propose multi-file changes, and execute commands. Copilot offers Sol, Terra, and Luna models for different tasks; Cursor provides diff-style autocomplete and task panels; Windsurf generates step-by-step plans and iterates on code. These tools move beyond chat-based coding by integrating directly into editors and terminals.