OpenAI’s 12-hour prompt cache pays off from the third request
GPT-5.6 and later can keep a cached prefix for 12 hours at a 2.5x write price. Worked break-even numbers, and the traps in the docs.
GPT-5.6 and later can keep a cached prefix for 12 hours at a 2.5x write price. Worked break-even numbers, and the traps in the docs.
Stéphane Cardon, network cybersecurity engineer. Architecture, LAN and WLAN, system administration. PacketNebula holds the tools and answers he wanted for his own work.
Copyright © 2026 Stephane Cardon.
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