This Build Hour session, led by OpenAI's Michaela and Emre Okcular, focuses on Context Engineering as a critical discipline for building robust, long-running AI Agents. Emre defines context engineering as both an art and a science, emphasizing its role in optimizing LLM performance beyond just model quality or prompt engineering. The session identifies four common failure modes for long-running agents: context bursting, conflict, poisoning, and noise. To address these, three core strategies are introduced: Reshape + Fit (adapting context window through trimming, compaction, summarization), Isolate + Route (directing context to specific sub-agents), and Extract + Retrieve (creating high-quality, retrievable memories). Emre demonstrates these techniques using a Next.js and OpenAI Agents SDK-based IT troubleshooting agent, showcasing how summarization can create persistent, cross-session memory for personalized interactions. The session concludes with best practices for Agent memory design, including understanding typical context, deciding when to remember and forget, and implementing memory-specific evaluations, offering valuable insights for developers aiming to build stateful and intelligent AI applications.

