YAGNI decision-ladder for agents

A pre-generation guardrail pattern: force an agent down an ordered ladder of cheaper options before it writes new code — (1) is it even needed, (2) reuse existing code, (3) standard library, (4) native platform feature, (5) an already-installed dependency, (6) a one-liner — writing bespoke code only as the last rung. Curbs the agent tendency to over-engineer and pull in dependencies; 'the best code is the code you never wrote.'

Connected concepts

Ponytail (lazy-senior-dev agent guide), Keep quality left, Novelty / anti-duplication guard, Guides & sensors