What does a perfect result look like? Without this answer, every later step builds on sand.
Right after Step 1. Before you write a single instruction. Before you write any knowledge files.
Pull actual outputs you have produced that are "really good". Real ones, not made-up. If you have not produced any yet, generate them by hand first and use those.
Structure, length, tone, format, the recurring moves. The patterns are the standard. Bullet list, half a page is enough.
How long, what sections, what order, what format (Markdown, HTML, JSON, paragraphs).
Voice, sentence length, words you use, words you never use, level of certainty, where it surprises.
Continue with skill-creator. Step 2: output standard. Ask me for 3–5 real past outputs of this task that I consider "really good". Then extract the patterns: structure, length, tone, format, recurring moves. Write the output standard as a markdown doc next to the skill.
Skills without examples drift toward the average. With three to five real reference outputs, Claude has something to aim at every single run.