Claude Code v2.1.280

Claude Code v2.1.280 was released on September 22, 2026.

Summary

Claude Code 2.1.280 brings Claude Opus 5.5 as your new default model with a massive 1M context window and faster processing, plus improved mouse controls in fullscreen mode for smoother navigation. Check the full release notes to see all the enhancements under the hood.

Release Context

This was the 224th Claude Code release of 2026 tracked by Havoptic.
It shipped 4 days after Claude Code v2.1.278 (September 19, 2026).
Claude Code: ships every 0.8 days — 28 releases in the last month.

Why it matters: Opus 5.5 Now Default With Million Token Context.

Introducing Claude Opus 5.5, the first model in our new Claude 5.5 family. It performs at the level of Claude Fable 5.1 for most tasks, and costs 40% less to run than Opus 5. https://t.co/Q9C2VKQ79f — Claude

Shipped around the same time

Within 3 days of this release, other AI coding tools also shipped:

GitHub Copilot CLI v1.0.88 (September 22, 2026)
OpenAI Codex CLI rust-v0.156.0 (September 22, 2026)
Antigravity CLI v1.2.8 (September 22, 2026)
GitHub Copilot CLI v1.0.87 (September 21, 2026)
Grok Build v1.0.40 (September 20, 2026)

Compare Claude Code: vs OpenAI Codex CLI · vs Cursor · vs Gemini CLI · vs Kiro CLI · vs GitHub Copilot CLI · vs Devin Desktop · vs Antigravity CLI · vs Grok Build

Release Notes

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
Added mouse support to more lists in fullscreen mode: the wheel scrolls the /skills list, and a skill's state options in /plugin can be clicked
Added CLAUDECODEMAXMCPDESCRIPTIONLENGTH to change the 2,048-character cap on MCP tool descriptions and server instructions for every MCP server in the session
Added hook output si

View original release

Other Recent Claude Code Releases

v2.1.277 (September 18, 2026)
v2.1.276 (September 18, 2026)
v2.1.275 (September 17, 2026)
v2.1.274 (September 16, 2026)
v2.1.273 (September 15, 2026)

All Claude Code releases · All AI coding tool releases on Havoptic