A 400 response usually indicates a validation failure or missing required parameters, but can trigger for many reasons. This sample 400 error represents an attempt to view a storage group that doesn't exist:

{
  type: 'validation-error',
  title: 'Validation failure',
  instance: '9378a1a8-bead-4ceb-931c-a8c0004cb1e2',
  status: 400,
  detail: 'Validation failed. Please review the errors.',
  errors: [
    {
      type: 'error-types/invalid-value',
      title: 'Invalid value',
      detail: 'Unable to find the given storage group.',
      field: 'storageGroupId'
    }
  ]
}