---
name: principle-encode-lessons-in-structure
description: "Apply when you catch yourself writing the same instruction a second time, or notice a recurring correction. Encode the rule as a lint, metadata flag, runtime check, or script instead of more text."
user-invocable: false
---

# Encode Lessons in Structure

Encode recurring fixes in mechanisms (tools, code, metadata, automation) instead of textual instructions. Every error, human correction, and unexpected outcome is a learning signal. Capture it, route it, and close the loop.

Textual instructions are easy to miss. Structural mechanisms enforce the rule without cooperation.

**Pattern:** when you catch yourself writing the same instruction a second time, ask whether it can be a lint rule, a metadata flag, a runtime check, or a script. If yes, encode it and delete the instruction. If no (it requires judgment), make the instruction more prominent and add an example of the failure mode.

**Pick the strongest mechanism.** When more than one mechanism would work, choose the strongest the situation allows (an unrepresentable state that cannot compile, then a lint or banned API that fails CI, then a canonical helper, then a runtime check), because agents copy whatever the surrounding code already does and a weaker guard becomes the next template.

**Corollary:** If the fix is structural, only use the structural fix. The instruction is the symptom.

When the human intervenes or tests fail, decide if it's a one-off or a pattern. Route it: one-off -> brain note, recurring fix -> skill or lint rule, systemic issue -> principle. Close the loop: don't just record; apply now or create a concrete todo.

**Anti-patterns:**
- Acknowledging without recording ("I'll keep that in mind" does not persist)
- Recording without routing (a brain note about a lint rule that should exist is wasted unless the lint rule gets implemented)
- Fixing without generalizing (fixing one instance while leaving the recurring pattern intact)