# An update on recent Claude Code quality reports Anthropic

<https://www.anthropic.com/engineering/april-23-postmortem>

- Host: [anthropic.com](https://links.thingelstad.xyz/hosts/anthropic.com/)
- Saved: April 30, 2026 (2026-05-01T02:29:49Z)
- Record: https://links.thingelstad.xyz/links/2ab8741a9842/
- JSON: https://links.thingelstad.xyz/links/2ab8741a9842.json

## What Jamie wrote

There were grumbles about Claude Code getting less smart and here Anthropic shares what they changed that caused this and what they did to fix it. It is an interesting read because the three changes span a change in a default, an actual bug, and a reasoning change. When I read this it feels like the kind of thing that agentic engineering teams are going to need to be really good at. It also strikes me as a difference between products and agents. If you build a product and ship it, minus bugs it will behave deterministically. The last item on Claude's issue was a change in behavior that impacted coding performance. That isn't a feature change. This is what "performance management" for agents looks like.

## Facts

- Kind: [Page](https://links.thingelstad.xyz/kinds/page/)

## Appears in

- [WT346: Weekly Thing 346 / Wuphf, Landsat, Eclipse](https://weekly.thingelstad.com/archive/346/), Notable

## Same host

- [Introducing Sonnet 4.6 Anthropic](https://links.thingelstad.xyz/links/509dbec071b6/) (anthropic.com, February 19, 2026)
- [Project Glasswing: Securing critical software for the AI era Anthropic](https://links.thingelstad.xyz/links/3eade88d874f/) (anthropic.com, April 9, 2026)
- [Introducing Claude Design by Anthropic Labs](https://links.thingelstad.xyz/links/0573c40907ec/) (anthropic.com, April 21, 2026)
- [How people ask Claude for personal guidance Anthropic](https://links.thingelstad.xyz/links/dca347043ead/) (anthropic.com, May 5, 2026)
- [Redeploying Fable 5](https://links.thingelstad.xyz/links/24a872edf329/) (anthropic.com, June 30, 2026)

## Saved the same week

- [Beware Software Brain | The Verge](https://links.thingelstad.xyz/links/8ff7a956079c/) (theverge.com, April 30, 2026)
- [Your Name in Landsat 🛰️](https://links.thingelstad.xyz/links/d2fef233db78/) (science.nasa.gov, April 30, 2026)
- [Using the internet like its 1999 - The Universe of Joshua Blais](https://links.thingelstad.xyz/links/d5ee0a9bc52f/) (joshblais.com, April 30, 2026)
- [honker: SQLite extension + bindings for Postgres NOTIFY/LISTEN semantics](https://links.thingelstad.xyz/links/0f71d692c0ea/) (github.com, April 30, 2026)
- [Microsoft launches ‘vibe working’ in Word, Excel, and PowerPoint | The Verge](https://links.thingelstad.xyz/links/0b7f5c69fb16/) (theverge.com, April 30, 2026)

## Elsewhere

- Wayback Machine: https://web.archive.org/web/*/https://www.anthropic.com/engineering/april-23-postmortem