Simon Willison’s Weblog

22nd September 2026

Release llm-anthropic 0.29 — LLM access to models by Anthropic, including the Claude series

Adds support for Claude Opus 5.5:

llm -m claude-opus-5.5 "prompt goes here"

Posted 22nd September 2026 at 5:14 pm

Recent articles

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This is a beat by Simon Willison, posted on 22nd September 2026.

llm 639 anthropic 348

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