GPT-5.2 in Cursor: Hour Long Coding Tasks & Testing

Description

GPT-5.2 dropped today and I'm testing it inside Cursor on real projects. OpenAI says GPT-5.2 Pro can run for up to an hour on complex coding tasks. Cursor just shipped debug mode and a new design editor. Time to see if any of this actually works. What I'm testing: - Multiplayer soccer game (5v5, 10 players) built from scratch - Lanikai Canoe Club app - full SaaS with Convex database, Clerk auth, the whole stack - Taking a spec Opus 4.5 generated and handing it to GPT-5.2 to see how far it gets Also walking through my prompting workflow for going from idea to spec to implementation. We'll see what breaks. Cursor 2.2 changelog: https://cursor.com/changelog/2-2 GPT-5.2 announcement: https://openai.com/index/introducing-gpt-5-2/ Discord: https://rfer.me/discord Wispr Flow: https://rfer.me/wispr Timestamps 00:00:00 GPT-5.2 just dropped today. 00:01:21 Outlining the first project: A full SaaS spec. 00:01:44 Outlining the second project: A multiplayer soccer game. 00:02:48 Discussing Cursor's new v2.2 with debug and design modes. 00:04:40 Exploring GPT-5.2's different context and reasoning models in Cursor. 00:07:00 Explaining the prompt engineering workflow using Opus 4.5 to generate specs. 00:09:00 Showcasing a prototype SaaS built by Base44 from a single spec prompt. 00:10:48 Setting up the starter kit in Cursor with Convex, Next.js, and Clerk. 00:11:45 Starting the build in Cursor by handing off the Opus-generated spec. 00:18:17 Improving the plan by creating a V1 spec file for the agent to reference. 00:21:41 Using Exa code and ref.search MCPs to add context for Convex conventions. 00:28:18 Starting the first major automated build with GPT-5.2. 00:35:32 Reviewing the backend and schema code generated by GPT-5.2. 00:42:48 Pivoting to the second project: Architecting the multiplayer soccer game. 00:46:26 Prompting Opus 4.5 and ChatGPT 5.2 Pro to research and plan the game. 00:47:53 Live discovery of SpaceTimeDB, a database for games, from chat. 00:52:53 Opus 4.5 compares Convex vs. SpaceTimeDB for the game's backend. 01:03:15 Demonstrating the use of Wispr Flow for dictating specs via voice. 01:04:13 Reviewing the game concept based on the classic NES World Cup game. 01:19:32 Announcing the "12 Days to Christmas" challenge to build the game live. 01:27:38 Reviewing the massive 2,274-line game architecture spec generated by Opus 4.5. 01:40:29 Using ChatGPT 5.2 Pro to learn the basics of Rust for the game's backend. 01:49:35 Creating a reusable Claude Skill called "App Architect" from the session. 01:58:52 Kicking off the soccer game build in Cursor with GPT-5.2-Fast. 02:07:38 GPT-5.2 agent starts scaffolding the Next.js app for the game. 02:13:57 Storytime: Working on a secret Apple project with no recovery port. 02:18:12 Explaining the complexities of ensuring reliable OTA updates. 02:19:53 Discussing his personal reasons for no longer wearing an Apple Watch. 02:20:56 Final thank you and wrapping up the stream. #openai #cursor #gpt52 #chatgpt #aicoding