Opus 4.5 Collapsed Six Months of Development Work Into One Week

If you want to learn more about Opus 4.5, Kieran Klaassen and I are hosting a Claude Code Camp on Opus 4.5 exclusively for paid subscribers on Friday (that’s tomorrow) at 12 p.m. ET. Sign up and reserve your spot.—Dan Shipper

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Humans have always had two main intuitions about what we’ll find when we travel to the end of the earth:

1. An edge where the known world falls off into nothingness, chaos, or monsters
2. A new vista where unexplored, lush, and perhaps perilous territory extends toward a new horizon

The first is terrifying, a place to be avoided. The second represents possibility and an entirely new world.

These days most new AI model releases are incremental. Sometimes, though, a new model brings us right up to the edge of the known and allows us to take a peek at what lies beyond. Is it nothingness, dragons, or a new horizon?

Anthropic’s Opus 4.5 is one of those models, and I’ve been peering over the edge for about a week now. Here’s what’s over the horizon:

1. We are in a new era of autonomous coding. You can build astonishingly complex apps without looking at a single line of code.
2. Prompt-native apps are now possible. You can use Opus 4.5 as a general-purpose agent to power your app’s features. This turns new features into an exercise in prompt-writing, rather than coding.

The infinite vibe coding machine

The first step change with Opus 4.5 is the amount of autonomous coding that is now possible.

Over the last week, I built an iOS reading companion app with a comprehensive suite of features. It’s the kind of thing that previous models could one-shot as a demo, but would start to trip over themselves after a while if I didn’t sit down and look at the code myself. I started writing the app with Anthropic’s Sonnet 4.5 and OpenAI’s Codex, but gave up pretty quickly because they were getting lost in loops of errors that I didn’t have time to debug.

Opus 4.5 is different. I didn’t write a single line of code. I didn’t even look at the code. I just talked into my computer with Monologue. And out came a complete reading companion.

I can photograph any book page, and it identifies the work, analyzes the passage, and connects it to larger themes—with zero clicks. I can tap a character name for a spoiler-free summary of everything the character has done so far in the book. It even automatically researches and downloads the original text (if the book is in the public domain) plus academic secondary sources to help with its analysis, and writes a custom introduction for each book to tell me why I might be interested in it.