Boundary Discipline
Trigger
At parsing, framework, process, network, storage, or user-input boundaries.
Rule
Validate and normalize at boundaries, trust internal invariants, and keep business logic free of adapter noise.
Application
- Name the concrete decision this principle changes.
- Apply the rule to that decision, not as a decorative citation.
- Prefer evidence from the current repository/runtime over generic preference.
- If the principle conflicts with an explicit user constraint, keep the constraint and state the tradeoff.