Implicit Contract
Kind: anti-pattern
Layer: Enforcement Core
Aliases: Implicit Payloads
Record: architecture:implicit-contract
Severity: discouraged
Scope: contract_compatibility, causality_ordering
Formed by: Encode assumptions in code behavior, naming, ordering, timing, side effects, or undocumented payload shapes instead of declaring them as explicit contracts.
Canonical: Ontology
A defect in which a boundary's assumptions, including the shape and meaning of the data it passes, live in behavior, naming or ordering rather than in a declared contract.
Listed in Architecture principles, after Schema Drift and before Hardcoded Configuration.