schema-code-type-string

Requires an error schema's code property to use type: string.

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

Intent

String error codes remain stable when teams use names, prefixes, or numeric-looking values with leading zeros.

Flags

A code property in the first media-type schema of a 4xx or 5xx response when its type is not string. A missing type is also reported.

Does not flag

String codes, error schemas without code, and non-error responses. Use error-schema-code to require the property itself.

See it fail

responses:
  '400':
    description: Invalid request
    content:
      application/problem+json:
        schema:
          type: object
          properties:
            code:
              type: integer

Diagnostic: Error property `code` should be string.

Fix it

responses:
  '400':
    description: Invalid request
    content:
      application/problem+json:
        schema:
          type: object
          properties:
            code:
              type: string

Configure

profiles:
  default:
    rules:
      extends: [recommended]
      override:
        schema-code-type-string: error

Nearby: error-schema-code, schema-message-type-string.