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[ARTICLE · art-122836] src=simonwillison.net ↗ pub= topic=developer-tools verified=true sentiment=· neutral

llm-anthropic 0.28

Anthropic released llm-anthropic 0.28 on 2nd September 2026, which now displays reasoning traces by default for supported models and introduces a new `llm_anthropic.ClaudeRefusal` exception for when Claude throws a refusal.

read1 min views32 publishedSep 2, 2026

2nd September 2026

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.

Recent articles #

- [The Pelican comparison grid for Astra is pretty interesting](https://simonwillison.net/2026/Sep/4/astra-pelicans/) - 4th September 2026
- [OpenAI's rogue agents were caught communicating via public wikis](https://simonwillison.net/2026/Sep/4/rogue-agent-wikis/) - 4th September 2026
- [Claude's new system prompt really doesn't want to reproduce song lyrics](https://simonwillison.net/2026/Sep/2/claudes-new-system-prompt/) - 2nd September 2026
source & further reading
simonwillison.net — original article Quoting Anthropic Frontier Red Team Photo Scrubber — local face blur & metadata removal Quoting @joedaroo
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