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24th August 2026

Release llm-anthropic 0.27 — LLM access to models by Anthropic, including the Claude series

This release of the Anthropic plugin for LLM mainly provides compatibility with the recently released anthropic v1.0.0 Python library, which switches from httpx to httpx2. OpenAI made the same change in their v3.0.0 release two weeks ago.

Anthropic provide this migration guide for upgrading to 1.0, so I prompted Fable 5 in Claude Code with:

Upgrade to anthropic>=1 - read https://raw.githubusercontent.com/anthropics/anthropic-sdk-python/refs/heads/main/MIGRATION.md and get the tests passing

Here's the resulting PR.

This is a beat by Simon Willison, posted on 24th August 2026.

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