# Valid Interfaces and Contracts

> Interfaces and contracts are valid

Record: `reasoning:invariant-valid-interfaces-and-contracts`
Kind: invariant
Canonical: https://banes-lab.com/ontology/reasoning#reasoning-invariant-valid-interfaces-and-contracts

Listed in [Reasoning records](https://banes-lab.com/api/records/reasoning.md), after [Correct Interactions](https://banes-lab.com/records/reasoning/invariant-correct-interactions.md) and before [Acceptable Execution Time](https://banes-lab.com/records/reasoning/invariant-acceptable-execution-time.md).

## Surfaces

- [interface-correctness](https://banes-lab.com/records/reasoning/test-surface-interface-correctness.md)

## Linked from

- [The test surfaces](https://banes-lab.com/ontology/reasoning/the-test-surfaces.md)