Claude Sonnet 5.5 Cache Read Price Cut

Anthropic halved the API price of cached input on Claude Sonnet 5.5, for developers paying per token on the Claude Platform.

Prompt cache reads on Sonnet 5.5 drop from $0.20 to $0.10 per million tokens, now 0.05x the base input price instead of 0.1x
Input stays at $2 and output at $10 per million tokens; cache writes and all other prices are unchanged
Anthropic says this makes Sonnet 5.5 about 20% cheaper on most agentic work
API only; Claude Code usage limits do not change