Prompt caching is currently in public beta for Claude. It was announced on August 15, 2024 and is available for Claude 3.5 Sonnet, Claude 3 Opus, and Claude 3 Haiku models. The beta status allows Anthropic to gather feedback and iterate on the feature before a full release. Prompt caching offers significant benefits, including cost reduction up to 90% and latency reduction up to 85% for long prompts, by allowing developers to cache frequently used context between API calls.