【速報】OpenAIがGPT-5.4をリリース！進化した「思考」モデルの正体とは？

OpenAIから最新の推論モデル『GPT-5.4』が突如発表されました！公開された「Thinking System Card」によると、これまでのモデル以上に複雑な思考プロセスと推論能力が強化されているとのこと。詳細は以下のリンクからチェック可能です。 ・公式サイト（System Card）: https://openai.com/index/gpt-5-4-thinking-system-card/ ・公式X（旧Twitter）の告知: https://x.com/OpenAI/status/2029620619743219811 ついに「思考するAI」が次の次元へ。エンジニアとして、推論能力の向上や実務への影響が非常に気になるところですね。

"GPT‑5.4 interprets screenshots of a browser interface and interacts with UI elements through coordinate-based clicking to send emails and schedule a calendar event."

They show an example of 5.4 clicking around in Gmail to send an email.

I still think this is the wrong interface to be interacting with the internet. Why not use Gmail APIs? No need to do any screenshot interpretation or coordinate-based clicking.

The marquee feature is obviously the 1M context window, compared to the ~200k other models support with maybe an extra cost for generations beyond >200k tokens. Per the pricing page, there is no additional cost for tokens beyond 200k: https://openai.com/api/pricing/ (https://openai.com/api/pricing/)

Also per pricing, GPT-5.4 ($2.50/M input, $15/M output) is much cheaper than Opus 4.6 ($5/M input, $25/M output) and Opus has a penalty for its beta >200k context window.

I am skeptical whether the 1M context window will provide material gains as current Codex/Opus show weaknesses as its context window is mostly full, but we'll see.

Per updated docs (https://developers.openai.com/api/docs/guides/latest-model (https://developers.openai.com/api/docs/guides/latest-model)), it supercedes GPT-5.3-Codex, which is an interesting move.

I’m sure the military and security services will enjoy it.

The "RPG Game" example on the blogpost is one of the most impressive demo's of autonomous engineering I've seen.

It's very similar to "Battle Brothers", and the fact that RPG games require art assets, AI for enemy moves, and a host of other logical systems makes it all the more impressive.

I've only used 5.4 for 1 prompt (edit: 3@high now) so far (reasoning: extra high, took really long), and it was to analyse my codebase and write an evaluation on a topic. But I found its writing and analysis thoughtful, precise, and surprisingly clearly written, unlike 5.3-Codex. It feels very lucid and uses human phrasing.

It might be my AGENTS.md requiring clearer, simpler language, but at least 5.4's doing a good job of following the guidelines. 5.3-Codex wasn't so great at simple, clear writing.

Today, we’re releasing <..> GPT‑5.3 Instant

Today, we’re releasing GPT‑5.4 in ChatGPT (as GPT‑5.4 Thinking),

Note that there is not a model named GPT‑5.3 Thinking

They held out for eight months without a confusing numbering scheme :)

What a model mess!

OpenAI now has three price points: GPT 5.1, GPT 5.2 and now GPT 5.4. There version numbers jump across different model lines with codex at 5.3, what they now call instant also at 5.3.

Anthropic are really the only ones who managed to get this under control: Three models, priced at three different levels. New models are immediately available everywhere.

Google essentially only has Preview models! The last GA is 2.5. As a developer, I can either use an outdated model or have zero insurances that the model doesn't get discontinued within weeks.

I find it quite funny how this blog post has a big "Ask ChatGPT" box at the bottom. So you might think you could ask a question about the contents of the blog post, so you type the text "summarise this blog post". And it opens a new chat window with the link to the blog post followed by "summarise this blog post". Only to be told "I can't access external URLs directly, but if you can paste the relevant text or describe the content you're interested in from the page, I can help you summarize it. Feel free to share!"

That's hilarious. Does OpenAI even know this doesn't work?

So let me get this straight, OpenAi previously had an issue with LOTS of different models snd versions being available. Then they solved this by introducing GPT-5 which was more like a router that put all these models under the hood so you only had to prompt to GPT-5, and it would route to the best suitable model. This worked great I assume and made the ui for the user comprehensible. But now, they are starting to introduce more of different models again?

We got:

• GPT-5.1

• GPT-5.2 Thinking

• GPT-5.3 (codex)

• GPT-5.3 Instant

• GPT-5.4 Thinking

• GPT-5.4 Pro

Who’s to blame for this ridiculous path they are taking? I’m so glad I am not a Chat user, because this adds so much unnecessary cognitive load.

The good news here is the support for 1M context window, finally it has caught up to Gemini.

Whoa, I think GPT-5.3 Instant was a disappointment, but GPT-5.4 is definitely the future!