openapi: 3.0.0
info:
  title: Greeting API
  version: 1.0.0
paths:
  /api/greeting:
    get:
      operationId: getGreeting
      summary: Return a greeting
      responses:
        "200":
          description: A greeting
          content:
            application/json:
              schema:
                type: object
                required:
                  - message
                properties:
                  message:
                    type: string