Claude Code 2.1.280 metadata reveals Opus 5.5 and Haiku 4.5 model IDs, 65% prompt token jump
ClaudeCodeLog · x · 2026-09-23
ClaudeCodeLog's deeper parse of Claude Code 2.1.280 shows:
- New model IDs: claude-opus-5-5 and claude-haiku-4-5; new commands like edit-chrome-settings, edit-sandbox-settings, edit-skill-overrides; new CLAUDECODEPLUGINDIRS env var
- Removed legacy model IDs including claude-code-user, claude-shallow- and o5-2q
- Released 2d 19h after 2.1.278; bundle grew +1,120.3 kB (+2.2%), prompt files +4 (+26.7%), prompt tokens +10,204 (+65.2%)
- Prompt token mix shifted: tools 73.2%→67.3%, system 26.8%→32.7%
Related event: Claude Code 2.1.280 Ships with Opus 5.5 as Default Model(3 posts)→
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