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Claude Code character

Claude Sonnet 4, Opus 4.1, Haiku 3.5

4 products from Anthropic

Quality report · Confirmed by the lab

Anthropic confirms three infrastructure bugs degraded Claude responses in August and September 2025

Anthropic published a postmortem saying three separate infrastructure bugs, the first introduced on August 5, intermittently degraded Claude's response quality until early September. A load balancing change on August 29 increased affected traffic. The Hacker News thread drew 381 points and 116 comments.

Who is affected:
Users of Claude Sonnet 4, Opus 4 and 4.1, and Haiku 3.5 on the Claude API and in Claude Code between August 5 and mid-September 2025.
What to do:
No action needed. Anthropic says all three bugs are fixed.

Source

"Between August and early September, three infrastructure bugs intermittently degraded Claude's response quality."

Anthropic Engineering, A postmortem of three recent issues

Published

Open the sourceanthropic.com

Another source

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