Devin
Cognition's autonomous AI engineer that plans, codes, tests, debugs, and opens PRs unattended. Now shipped alongside Windsurf (acquired July 2025) as the async half of Cognition's stack — Devin runs async tasks, Windsurf is the in-editor surface.
Claude Code
Terminal-first agentic coding assistant from Anthropic. Full MCP client support, codebase-aware, runs multi-step tasks autonomously.