# DevDay 2025: Apps SDK, Agent Kit, MCP, Codex and why Prompting is More Important than Ever Page: https://stenobird.com/podcast/latent-space-ai-engineer/devday-2025-apps-sdk-agent-kit-mcp-codex-and-why-prompting-is-more-important-than-ever Text version: https://stenobird.com/podcast/latent-space-ai-engineer/devday-2025-apps-sdk-agent-kit-mcp-codex-and-why-prompting-is-more-important-than-ever.md Podcast: [Latent Space: The AI Engineer Podcast](https://stenobird.com/podcast/latent-space-ai-engineer) Published: 2025-10-07T15:00:00+00:00 Episode link: https://www.latent.space/p/devday-2025-apps-sdk-agent-kit-mcp Audio file: https://api.substack.com/feed/podcast/186621796/0a66667bca1f94b356c94afbea26300a.mp3 Processing state: processed JSON: https://stenobird.com/v1/public/podcasts/latent-space-ai-engineer/episodes/devday-2025-apps-sdk-agent-kit-mcp-codex-and-why-prompting-is-more-important-than-ever Duration seconds: 2708 ## Resource At OpenAI DevDay , we sit down with Sherwin Wu and Christina Huang from the OpenAI Platform Team to discuss the launch of AgentKit - a comprehensive suite of tools for building, deploying, and optimizing AI agents. Christina walks us through the live demo she performed on stage, building a customer support agent in just 8 minutes using the visual Agent Builder , while Sherwin shares insights on how OpenAI is inverting the traditional website-chatbot paradigm by embedding apps directly within ChatGPT through the new Apps SDK. The conversation explores how OpenAI is tackling the challenges developers face when taking agents to production - from writing and optimizing prompts to building evaluation pipelines. They discuss the decision to adopt Anthropic’s MCP protocol for tool connectivity, the importance of visual workflows for complex agent systems, and how features like human-in-the-loop approvals and automated prompt optimization are making agent development more accessible to a broader range of developers. Sherwin and Christina also reveal how OpenAI is dogfooding these tools internally, with their own customer support at openai.com already powered by AgentKit, and share candid insights about the evolution from plugins to GPTs to this new agent platform. They discuss the surprising persistence of prompting as a critical skill (contrary to predictions from two years ago), the challenges of serving custom fine-tuned models at scale, and why they believe visual agent builders are essential as workflows grow to span dozens of nodes. Guests: * Sherwin Wu: Head of Engineering, OpenAI Platform https://www.linkedin.com/in/sherwinwu1/ https://x.com/sherwinwu?lang=en * Christina Huang: Platform Experience, OpenAI https://x.com/christinaahuang https://www.linkedin.com/in/christ… ## Actions - request_transcript: `POST https://stenobird.com/v1/public/podcasts/latent-space-ai-engineer/episodes/devday-2025-apps-sdk-agent-kit-mcp-codex-and-why-prompting-is-more-important-than-ever/transcription-requests` — Idempotently request low-priority transcript generation for this episode. - read_markdown: `GET https://stenobird.com/podcast/latent-space-ai-engineer/devday-2025-apps-sdk-agent-kit-mcp-codex-and-why-prompting-is-more-important-than-ever.md` — Read the agent-friendly Markdown representation of this episode resource. A page view does not enqueue transcription. Agents should invoke `request_transcript` explicitly when they need this episode processed. ## Transcript Full transcripts are not published on public pages unless there is a clear rights basis.