Creating a Class from a Transformed Struct in Effect Typescript

export class Agent extends S.Class<Agent>("Agent")(S.Struct({
  id: S.String,
  name: S.String,
  description: S.String,
  rarity: _Rarity,
  market_hash_name: StringWithDefault,
  collections: S.Array(S.partialWith(Collection, { exact: true })),
  team: _Basic,
}).pipe(transformRarity)) {
  surreal = () => ({ ...this, id: generateSlug(this.name) });
}

function transformRarity<T extends S.Struct.Fields>(struct: S.Struct<T>) {
  return S.transform(
    S.Struct({
      ...struct.fields,
      rarity: S.String,
      color: S.String,
    }),
    {
      strict: true,
      decode: (data) => ({
        ...data,
        rarity: data.rarity.name,
        color: data.rarity.color,
      }),
      encode: (data) => data,
    },
  )(struct);
}