Cursor, Claude Code, and Codex Are Quietly Converging Into One Interoperable Coding Stack
The New Stack·medium signal
Analysis this week argues the three dominant agent surfaces — Cursor, Claude Code, and Codex — are merging into a single de-facto stack nobody explicitly designed, driven by shared protocols (ACP/MCP), portable AGENTS.md/CLAUDE.md config, and tools that bridge all three. Cognition's June 2 retirement of the Windsurf brand into Devin Desktop (defaulting to ACP) reinforced the trend. For builders the takeaway is to invest in protocol-portable config and skills rather than betting a workflow on one vendor's lock-in.