Model Wars

GPT 5.5 is here, and OpenAI’s latest model has it all. It’s fast enough to use constantly, personable enough to collaborate with, and assertive enough to carry a plan through serious engineering work. If you didn’t catch our full review, including benchmark results, Reach Test ratings, pricing, screenshots, and advice on when to reach for GPT-5.5 versus Opus 4.7, read our Vibe Check or rewatch the livestream, where we grilled OpenAI’s Dominik Kundel and Romain Huet on how they’re using the model.

But how will that shift the balance between OpenAI and Anthropic? That may be a product question as much as a model question. Every engineer Nityesh Agarwal and Monologue general manager Naveen Naidu weigh in.—Kate Lee

Inside Every

Codex versus Claude Code

This week, Anthropic tested removing Claude Code from the $20 Claude Pro plan, prompting an outcry from users and drawing jabs from OpenAI executives on X, perhaps feeling emboldened by the big launch they knew was coming.

The exchange kicked off a Slack debate between Nityesh Agarwal, our resident Claude Code devotee, and Naveen Naidu, who rides hard for OpenAI’s coding app Codex.

Nityesh’s take: Anthropic potentially raising prices is “simple market economics”—there is a huge demand for Claude products because they’re the best available, so they can charge more. On the other hand, OpenAI’s response underscores how frustrated the company has become playing catch-up as it scrambles to replicate Claude Code, Cowork, and skills. From a product standpoint, Claude in the browser and the Claude Code command line interface (CLI) are better than ChatGPT and Codex.

Naveen’s response: Anthropic’s models are powerful, but they also burn through way too much compute in production. OpenAI is much stronger on infrastructure, and GPT 5.5 is a token-efficient model. And while it’s true Anthropic is first to market with a lot of products and features, including computer use—which allows AI to operate your computer on your behalf—OpenAI is better at execution. Naveen consistently reaches for ChatGPT and the Codex desktop app, while he finds the Claude Code app too buggy to spend any time in.

Where they agree: The Claude Code app is, indeed, bad—Nityesh concedes he only uses the CLI. And both labs misjudged how much compute they would need, but in opposite directions: Anthropic is struggling to keep up with demand, whereas OpenAI has invested heavily in infrastructure and is now scrambling to get people to use its products.

Data point

It’s not just a grammatical pattern; it’s an AI tell

Four times.

That’s how much the usage of “not just a ___, it’s a ___” sentence construction rose in large U.S. company documents between 2023 and 2025, per Barrons.