Rich Text validation using "nodes"

We have been trying to do migrations using the “RichText” type for one of our fields.
Everythings seems to go fine until we started implementing validations of embedded assets and entries.

We have followed the example here:

Doing exactly that gives us an error when doing the migrations.

  errors: [
    {
      type: 'InvalidPayload',
      message: `A field can't have "nodes" as a validation.`
    },
    {
      type: 'InvalidPayload',
      message: `A field can't have "embedded-asset-block" as a validation.`
    }
  ] 

Our coded is pretty similar using these validations for nodes :

{
  nodes: {
    'embedded-entry-block': [
      { size: { max: 5 } }
    ],
    'embedded-asset-block': [
      { size: { max: 5 } },
    ]
  }
},

Giving the same error. Looking at the documentation for CMA it is impossible to find anything mentioning this “nodes” validation. However when doing the a backup for a space/environment the “nodes” validation structure is used for RichText types.

Is this a bug with the CMA or just us who are using it in a wrong way?
Would like to hear from someone who have solved this issue or knows more about it.

I have looked into the offline-api validators of the migration tool on github and come across this

This might be the root cause since it doesn’t allow a nodes type as validator.

Will file this issue on Github as well.