Anthropic: Opus 5.5 ~40% cheaper on long Claude Code sessions
Anthropic estimates Opus 5.5 costs about 40% less than Opus 5 on typical Claude Code traffic after cutting cache reads 60% and token prices 20%. Sessions now run 3.3x longer per prompt with 2.6x more context; API users can set a one-hour cache TTL, and forked subagents inherit the parent's cache.
