<!-- PM-Skills | https://github.com/product-on-purpose/pm-skills | Apache 2.0 -- Instrumentation Spec An instrumentation spec defines what analytics events to track, when to fire them, and what properties to include. It serves as a contract between product and engineering, ensuring consistent data collection that enables accurate measurement. Good instrumentation specs prevent the "we can't answer that question because we didn't track it" problem. When to Use - Before engineering implements a new feature - When defining analytics requirements for experiments - When auditing existing tracking…