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Tooling27 Sep 2026Lead storyThat day's edition

Claude Code 2.1.280 sets Opus 5.5 as the default Opus model, with a 1M-token window

The changelog lists Opus 5.5 at 4 dollars per million input tokens and 20 dollars per million output tokens.

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Quoted from code.claude.com on 2026-09-27: Added Claude Opus 5.5 ( claude-opus-5-5 ), now the default Opus model… Quoted from code.claude.com, checked 2026-09-27. “ Added Claude Opus 5.5 ( claude-opus-5-5 ), now the default Opus model — 1M context, $4/$20 per Mtok with $0.20/Mtok cache reads” quoted from code.claude.com · checked 2026-09-27
code.claude.com, quoted / Claude Code changelog · source · Quoted under the quotation exception; no licence granted

The Claude Code changelog from Anthropic lists 114 entries under version 2.1.280, dated September 22, 2026.

It fixes writes through a symlinked path being judged by their in-tree spelling: the permission prompt now names where the write actually lands, and acceptEdits, allow rules and auto mode no longer approve a write that lands outside the project tree.

The same release adds Claude Opus 5.5 as the default Opus model, with a 1M-token context window priced at 4 dollars/20 dollars per million input/output tokens and 20 cents per million tokens for cache reads.

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Check our sources

1 source, 3 claims. We opened the source and checked every sentence above against it.

1 Claude Code changelogAnthropic · 22 Sep 2026 · 3 claims Open the source

  1. Version 2.1.280, dated September 22 2026, fixes writes through a symlinked path being judged by their in-tree spelling rather than where the write lands.

    Fixed writes through a symlinked path being judged by their in-tree spelling: the prompt names where the write lands, and acceptEdits , allow rules and auto mode no longer approve one landing outside

  2. The release adds Claude Opus 5.5 as the default Opus model, with a 1M-token context window priced at $4/$20 per million input/output tokens.

    Added Claude Opus 5.5 ( claude-opus-5-5 ), now the default Opus model — 1M context, $4/$20 per Mtok with $0.20/Mtok cache reads

  3. The changelog lists 114 entries under 2.1.280.

    2.1.280 September 22, 2026

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