From the source
OpenAI GPT-5.6 models, giving users precise control over which parts of their prompts are cached and reused across requests, with a 90% discount on cached input and a 30-minute cache retention period.
Amazon· 30 JulIntroducing explicit prompt caching for OpenAI GPT-5.6 models on Amazon Bedrock
Capability change
From the source
Alongside the new models, GPT-5.6 introduces explicit prompt caching on Amazon Bedrock, a new capability that gives you precise control over which portions of your prompt are cached and reused across requests. Cached input is billed at a 90 percent discount (see the Amazon Bedrock pricing page) and stays available for reuse for 30 minutes.
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