How is an AI Skill different from a prompt?
A prompt is an instruction for one interaction. A Skill is intended to be reused: it defines the problem, sequence, evidence handling, output structure, decision points and limits so the method survives beyond one carefully worded message.
Why do boundaries matter?
Without boundaries, a reusable workflow can become confidently inconsistent. Good Skill design says what the method is for, what it should not infer, what evidence is missing, and when the user needs another expert, source or decision process.
How do I design a Skill?
I start with the recurring human method, not the model. Then I decompose the method into stages, define what information each stage needs, specify outputs and checks, and test where the workflow loses context, compresses too early or jumps from evidence to conclusion.
What makes a Skill worth reusing?
The Skill should make the process more repeatable, transparent or efficient than starting from a blank chat. If the only advantage is a longer prompt, it probably has not yet become a reusable method.
Can an AI Skill replace expert judgment?
Usually no. A Skill can structure work, surface issues, preserve context and improve consistency, but the appropriate human decision-maker still owns consequential judgments and domain-specific conclusions.