---
title: llm-anthropic 0.28
link: https://simonwillison.net/2026/Sep/2/llm-anthropic/
source: simonwillison-net
published: 2026-09-02T17:59:32Z
updated: 2026-09-02T17:59:32Z
first_seen: 2026-09-08T10:17:10.166315Z
labels:
- anthropic
- claude
- claude-mythos-fable
- llm
summary: 'Release: llm-anthropic 0.28 Claude Fable 5.1, reasoning traces are now displayed by default for models that support them, plus a new llm_anthropic.ClaudeRefusal exception for when Claude throws a refusal. Tags: llm, anthropic, claude, claude-mythos-fable'
content: extracted
html: 2026-09-02-llm-anthropic-0-28.html
---

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