Generating invalid code from Record

[stwiname]

I have this type on my server:

const Metadata = Type.Record(
  Type.String(),
  Type.Union([Type.String(), Type.Number(), Type.Boolean(), Type.Null()]),
  {
    description: `Metadata is for your internal use. It is not exposed to users through passes.\n The metadata is limited to ${METADATA_MAX_LENGTH} characters when serialized to JSON.`,
  },
)

Which results in the following openapi spec (full spec here passform-api.json)

"metadata": {
  "description": "Metadata is for your internal use. It is not exposed to users through passes.\n The metadata is limited to 5000 characters when serialized to JSON.",
  "type": "object",
  "additionalProperties": {
    "anyOf": [
      {
        "type": "string"
      },
      {
        "type": "number"
      },
      {
        "type": "boolean"
      },
      {
        "type": "null"
      }
    ]
  }
},

And the resulting generated code is invalid:

metadata: T.Optional(
  T.Object(
    {},
    {
      additionalProperties: {
        anyOf: [
          { type: 'string' },
          { type: 'number' },
          { type: 'boolean' },
          { type: 'null' }
        ]
      }
    }
  )
),

Im using "@sinclair/typebox": "^0.34.38"