Custom environment variables seem to be the way for this, as per the docs: In addition to Xcode and macOS versions, you can set custom environment variables for a workflow in its Environment section. These variables are available to custom build scripts you use to extend workflows. For example, set a secret environment variable to contain an API key you use in a custom build script that uploads a workflow’s artifacts to your server. Important To securely store an environment variable and make sure it doesn’t appear in any logs, select the Secret checkbox. https://developer.apple.com/documentation/xcode/xcode-cloud-workflow-reference#Custom-environment-variables

@Query will return an array of results. Similar to using fetch from a managed object context. Changing your code to this should work: @Query var model: [MyModel]