{
  "parameters": {
    "api-version": "2026-06-01",
    "billingAccountId": "100",
    "costAllocationRuleCheckNameAvailabilityRequest": {
      "name": "testRule",
      "type": "Microsoft.CostManagement/costAllocationRules"
    }
  },
  "responses": {
    "200": {
      "body": {
        "message": "A cost allocation rule with name testRule is already present for the billing account 100. Please specify a differnt name.",
        "nameAvailable": false,
        "reason": "AlreadyExists"
      }
    }
  },
  "operationId": "CostAllocationRules_CheckNameAvailability",
  "title": "CostAllocationRuleCheckNameAvailability"
}