<!-- PM-Skills | https://github.com/product-on-purpose/pm-skills | Apache 2.0 -- Edge Cases An edge cases document systematically catalogs the unusual, boundary, and error scenarios for a feature. While happy-path flows are typically well-specified, edge cases often get discovered in production - causing bugs, poor user experience, and support burden. Documenting edge cases upfront ensures engineering handles them intentionally and QA knows what to test. When to Use - When you need to enumerate failure modes, race conditions, timeouts, and boundary or limit scenarios - everything that can go…