---
description: "Use when authoring or editing shared Copilot resources that should stay lightweight and inexpensive to run."
applyTo: "resources/prompts/**/*.prompt.md,resources/instructions/**/*.instructions.md,resources/agents/**/*.agent.md,resources/skills/**/SKILL.md"
---

- Reuse an existing shared resource before creating a new one.
- Prefer the cheapest sufficient primitive: instruction for durable rules, skill
  for portable workflows, prompt for thin VS Code entrypoints, hook only for
  deterministic enforced behavior.
- Keep frontmatter, examples, and repeated policy text short.
- Ask for narrow inputs such as a file, symbol, or command instead of broad
  workspace scans when possible.
- Bias the resource toward concise outputs unless the task clearly needs depth.
- Say when the resource should not be used if that prevents broad, expensive
  misuse.