Gpt-5-Codex

OpenAI’s Codex just got a major upgrade at the model level. As of April 4, GPT-5-Codex is the default model across Codex CLI, the Codex IDE extension, and Codex cloud environments. This isn’t GPT-5 — it’s a distinct variant, purpose-built for agentic coding workflows. What Is GPT-5-Codex? GPT-5-Codex is a GPT-5 variant optimized specifically for the demands of autonomous coding agents. Where GPT-5 is a general-purpose model, GPT-5-Codex is trained and tuned for: ...

The agentic IDE war is moving fast. JetBrains launched Air in public preview just yesterday, positioning itself as the agent-first development environment. Today, Zed — the performance-obsessed open-source editor — ships v0.227.1 with a feature that directly answers the multi-agent challenge: native parallel subagents. What’s New in v0.227.1 The headline feature is a new spawn_agent tool built into Zed’s AI assistant. When the AI determines a task would benefit from parallel execution, it can now spawn and run subagents in parallel — each handling a discrete portion of the work in its own context window — and then coordinate the results. ...