# Substitutability

> Validate that every implementation of an abstraction preserves the abstraction’s behavior, accepts valid parent inputs, returns valid parent outputs, and does not strengthen forbidden constraints.

Record: `algo:substitutability`
Kind: architecture
Canonical: https://banes-lab.com/ontology/algorithms#algo-substitutability
Closure: https://banes-lab.com/json/records/algo/substitutability/closure