# Startup Skills: Ryan Carson > Every skill by Ryan Carson in the index, with a line saying when to use each one. I index these, I do not host them. Every entry points at the original author's repo and carries a source byline. ## Entries (1) - [PRD](https://github.com/snarktank/ralph/tree/main/skills/prd) by Ryan Carson: Use when a feature needs written requirements before anyone starts building it. ## Links - [Page](https://startupskills.dev/snarktank): the same list, for a person. - [The whole index](https://startupskills.dev/llms.txt): all 189 entries. - [Skills index](https://startupskills.dev/skills): every skill, with search.