Write a skill once and stop re-explaining yourself.

You write a skill, it drifts, you never open it again.

• →A skill is the difference between an agent that helps today and one that is better in three months. Almost nobody treats them that way.
• →Most published skill content is a list of prompts. Nobody shows the architecture, so nobody's second skill fits alongside their first.
• →Two skills that overlap will fight, and the agent will pick one at random. You find out from an output that is subtly wrong.
• →Skills regress silently. Nothing tells you a skill stopped firing, it just quietly stops being used.

Anatomy, composition, versioning, tests.

• 01
  The anatomy

  Frontmatter, triggers, examples and version, and what each part does to whether the skill actually loads when it should.
• 02
  Triggers that fire

  Writing the description so the skill loads on the phrasing people use, not the phrasing you had in mind when you wrote it.
• 03
  Composition

  Structuring skills so they stack instead of competing, including the scoping rule that stops two from claiming the same job.
• 04
  The seven to ship first

  The foundational set that pays for itself fastest, in the order I would add them to a new setup.
• 05
  Tests and versions

  How to catch a skill that has silently stopped firing, and the versioning habit that makes a rollback one line.

You, if you keep re-typing the same correction.

If you find yourself telling an agent the same thing every week, that correction is a skill you have not written yet. Start with one, and the pattern is obvious after that.

Why now Skills only recently became worth engineering properly. Once agents began loading them reliably from a description alone, the design of that description turned into the whole game.

The compounding is the real thing. Every correction you write down once is a correction you never make again, and after a few months the agent argues with you less because it already knows the answer.