The Responses API is our flagship API for building agents. This Build Hour shows how the Responses API unlocks persistent reasoning, hosted tools, and multimodal workflows for GPT-5.
Steve Coffey (API Engineering) covers:
• How to use built-in tools, call multiple tools in one API request, and preserve reasoning tokens across turns
• How the Responses API is faster and more cost-efficient
• Live demo: building a simulator to bring a day in the life of an OpenAI engineer to life
• Live Q&A
👉 Follow along with the code repo:
👉 Responses API Docs:
👉 Migrate to Responses API Guide:
👉 Sign up for upcoming live Build Hours:
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