16.5 Outcomes — none is a guess

Outcome	Means	Carries
planned	the goal is reachable, and one plan is cheapest	reads (the facts the goal reads), steps in run order — each with from, kind (view or rule), realm, the facts it adds and requires, what it reaches, whether the statement runs it, and its cost — the compiled statement, the input bindings, and the quote
unreachable	some fact the goal reads is made by no step on offer	missing — the fact, by name — and the planner’s detail
tie	two plans reach the goal at equal cost	both rival plans and the cost they share. Make the goal more specific; the planner never picks one
refused	the request cannot be planned as made — an untypable goal, an input that binds ambiguously, a plan whose steps do not compile together	reasons, each saying what to change
needsInput	English mode: the goal is sound, and needs an input nobody supplied	the goal, and needsInput: {type, why}
declined	English mode: no goal this world can reach answers the question	the reason, the missing facts when that is why, and the last goal written

Any outcome may carry diagnostics: the steps left out of planning, and why. An unreachable answer is also a precise brief: the missing fact names the step — or the realm — the world lacks.