---
features:
  - |
    Placement API microversion 1.18 adds support for the `required` query
    parameter to the `GET /resource_providers` API. It accepts a
    comma-separated list of string trait names. When specified, the API
    results will be filtered to include only resource providers marked with
    all the specified traits. This is in addition to (logical AND) any
    filtering based on other query parameters.

    Trait names which are empty, do not exist, or are otherwise invalid will
    result in a 400 error.