Cursor
VS Code fork with deep AI editing, multi-file context, and a powerful agent mode. The most popular AI editor by mindshare.
Spec Kit
Open-source scaffold from GitHub that operationalizes spec-driven development with AI coding agents. Creates structured .specify/ folders that serve as the source of truth for Claude Code, GitHub Copilot, and Gemini CLI — steering AI generation from upfront specs rather than improvised prompts.