Codex

Claude Code

Anthropic's official agentic coding CLI — lives in your terminal, reads entire codebases, and executes multi-step tasks autonomously. Surpassed $1B ARR within months of general availability. Multi-agent Code Review ships as a cloud feature that catches bugs before human reviewers see them. The tool Anthropic itself uses for ~60% of internal development work.

Cursor

The leading AI-native IDE, rebuilt around the idea that agents write most of the code. Cursor 3 (April 2026) introduced the Agents Window — run multiple agents in parallel across local worktrees, cloud, and remote environments — alongside Design Mode, which lets you click and drag on browser-rendered UI to give visual feedback to agents rather than describing it in text. Reached $2B ARR and $29B valuation by early 2026. The reference tool for serious AI-assisted development.

Windsurf

AI-native IDE built around Cascade — an agentic engine that reads your entire codebase and makes coordinated multi-file edits from natural language. Formerly Codeium. Ranked #1 in LogRocket's AI Dev Tool Power Rankings (Feb 2026). Now owned by Cognition (makers of Devin) following a dramatic 2025 acquisition after OpenAI's $3B bid collapsed and Google hired much of the leadership.

Gemini

Google's AI assistant with a 1M+ token context window, available on the web, in Android Studio, and across Workspace. Competes with Claude Code and Copilot for coding tasks.