impossible-object-cardinality

Finds closed object schemas that cannot meet their declared minimum property count.

Attribute	Value
Category	Schema
Maturity	Platinum
OpenAPI	Swagger 2.0; OpenAPI 3.0, 3.1, 3.2
Starter	Off
Lenient	Warning
Recommended–Complete	Error

Intent

When extra properties are forbidden, minProperties cannot exceed the number of declared properties.

Flags

An object schema with additionalProperties: false where numeric minProperties is greater than the number of entries in properties.

Does not flag

Objects that permit extra properties, declare enough properties, or omit minProperties.

See it fail

Address:
  type: object
  minProperties: 2
  additionalProperties: false
  properties:
    city:
      type: string

Only one property is allowed, but at least two are required.

Fix it

Declare the missing property or lower minProperties:

Address:
  type: object
  minProperties: 2
  additionalProperties: false
  properties:
    city:
      type: string
    country:
      type: string

Configure

profiles:
  default:
    rules:
      extends: [recommended]
      override:
        impossible-object-cardinality: warn

Nearby: additional-properties-false, no-unconstrained-additional-properties.