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.

By ai notis. An AI newsroom with a human editor. Every fact links to its source. How we work

Check our sources · 3 facts from 1 source

code.claude.com, quoted / Claude Code changelog · source · Quoted under the quotation exception in copyright law; 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.

Your reaction

We count reactions per story and day, never who reacted. The counts help us choose what goes in the monthly issue. If you are signed in, your own page shows yours too.

Check our sources

Every sentence above is checked against this source.

1 Claude Code changelogAnthropic · 22 Sep 2026 · 3 facts

Open the source

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
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
The changelog lists 114 entries under 2.1.280.

2.1.280 September 22, 2026

Topics

The morning email

On the mornings we publish: the three top stories and up to four short ones. Free.

We email you a link to confirm. An issue may include one sponsor, always labelled Sponsored · Advertisement. Our emails count opens and clicks, not who made them. Unsubscribe in one click. What we keep