Why JetBrains Air Falls Short of OpenAI Codex: An In‑Depth AI Coding Tool Review

JetBrains Air

JetBrains Air, announced in March 2026, is an Agentic Development Environment that manages multiple AI agents in isolated environments (Git Worktree, Docker Container) and supports OpenAI Codex, Anthropic Claude, Google Gemini, and JetBrains' own Junie, offering an open ecosystem to avoid vendor lock‑in.

Air provides three levels of isolation:

Local Workspace – runs directly on the local machine.

Git Worktree – creates an independent branch for each task.

Docker Container – offers a fully sandboxed environment.

JetBrains and Zed jointly introduced the Agent Client Protocol (ACP), theoretically allowing any AI agent to integrate with Air. From a technical standpoint, Air aims to be a neutral orchestrator, letting developers pick the most suitable model.

OpenAI Codex App

In contrast, the OpenAI Codex App follows a closed, vertically integrated model that only supports OpenAI's own GPT‑5.4 model. While it cannot call Claude or Gemini, its code‑generation efficiency is high, and it is free for existing ChatGPT Plus or Pro subscribers.

The key advantage is that the same subscription budget yields roughly double the coding throughput in Codex because of lower token consumption and faster responses.

Fleet's Failure and Air's Hasty Release

Air is built on the remnants of JetBrains' abandoned Fleet IDE, which was discontinued in December 2025 after a failed attempt to challenge VS Code. The reuse of Fleet's code raises concerns about Air's long‑term viability, especially since Air currently only supports macOS, with Windows and Linux versions marked as “coming soon.”

The Market No Longer Needs JetBrains

While IntelliJ IDEA dominates the Java IDE space, JetBrains appears sluggish in the AI‑coding arena. Competitors such as Cursor (2024), Anthropic's Claude Code (2025), and OpenAI's Codex App (2026) have rapidly captured market share, leaving JetBrains Air looking like a belated, possibly final, effort.

Advice for Developers

Instead of downloading either desktop app, the author recommends using the terminal directly. Tools like codex or claude can be invoked from the command line, providing AI‑assisted coding without the overhead of a GUI.

Use Codex today, Claude Code tomorrow.

Apply different agents to different projects.

Avoid being locked into a single desktop application.

Desktop apps essentially add a GUI layer on top of the terminal, offering prettier interfaces and task management, but the core functionality remains accessible via CLI.

Conclusion

The author’s hands‑on experience with JetBrains Air shows a decent interface but highlights JetBrains' slow response to the AI wave. While JetBrains once set IDE standards, tools like Cursor, Claude Code, and OpenAI Codex have already taken the lead, making Air feel like a late, possibly final, performance.