Data Scientist working across growth, product, machine learning and agentic analytics.https://jieyi-deng.github.io/enhttps://jieyi-deng.github.io/writing/more-than-prompting/https://jieyi-deng.github.io/writing/more-than-prompting/SKILL.md turns a prompt into an operational protocol. What that looks like in advertising analytics, where a fluent answer built on the wrong metric is worse than no answer at all.Tue, 17 Feb 2026 00:00:00 GMTagentsskill designad analyticsllmhttps://jieyi-deng.github.io/writing/my-2025-with-chatgpt/https://jieyi-deng.github.io/writing/my-2025-with-chatgpt/I exported a full year of ChatGPT history and analysed it. The conversation tree holds more than the official recap shows — including three different URL fields that reveal how retrieved sources actually reach an answer.Tue, 30 Dec 2025 00:00:00 GMTdata analysisllmpersonal analytics