responses API

DevDay 2025: Apps SDK, Agent Kit, MCP, Codex and why Prompting is More Important than Ever

Oct 7, 2025 · 44:52

Sherwin Wu and Christina Huang from OpenAI's platform team discuss the new AgentKit suite and Apps SDK, arguing that visual agent builders and prompt optimization remain critical for production AI. They detail AgentKit's components—Agent SDK, visual Builder, Evals, and Tool Registry—and how Apps SDK inverts the website-chatbot paradigm by embedding apps inside ChatGPT. OpenAI adopted Anthropic's MCP protocol for tool connectivity, and the team dogfoods these tools for their own customer support at openai.com. They explain that automated prompt optimization and evaluation pipelines are essential for scaling agents, and share how Codex is used internally for code generation and PR reviews. The episode also covers the Service Health Dashboard for real-time API SLO tracking, reflecting OpenAI's reliability investments.

The new OpenAI Agents Platform: CUA, Web Search, Responses API, Agents SDK!!

Mar 11, 2025 · 25:39

OpenAI's Nikunj Handa and Romain Huet join host Swyx to announce their new Agents Platform, including the Responses API, Web Search, File Search, Computer Use tools, and an upgraded Agents SDK. The Responses API unifies Chat Completions and the Assistants API, offering free state storage for 30 days and acting as a strict superset for future agentic workflows; Chat Completions remains supported, but the Assistants API will sunset in first half 2026. Web Search is available both as a built-in tool in Responses and as a fine-tuned GPT-4o Search Preview model in Chat Completions, achieving 90% accuracy on simple QA compared to 30% for GPT-4o. The File Search tool gains metadata filtering, while Computer Use—powering OpenAI's Operator—enables browser automation via screenshots and action signals, described as the "GPT-2 of computer use." The Agents SDK builds on the Swarm experiment, adding type support, guardrails, handoffs, and tracing in the OpenAI dashboard, with plans to tie traces to evals and reinforcement fine-tuning.