Claude Code 2.1.280 Ships with Opus 5.5 as Default Model

Claude Code 2.1.280 rolls out 114 CLI changes, making Claude Opus 5.5 (1M context, $4/$20 per million tokens) the default model, with new identifiers also hinting at Haiku 4.5.

2026-09-23 ~ 2026-09-23 · 3 related posts

• Claude Code 2.1.280 ships 114 CLI changes, defaults to Opus 5.5 at $4/$20 per Mtok — ClaudeCodeLog · 2026-09-23
• Claude Code 2.1.280 ships 114 changes, makes Opus 5.5 with 1M context the default — ClaudeCodeLog · 2026-09-23
• Claude Code 2.1.280 metadata reveals Opus 5.5 and Haiku 4.5 model IDs, 65% prompt token jump — ClaudeCodeLog · 2026-09-23