REST API: Filter for related Entries

[Kilsicles]

Updated

Using the statamic REST API, I want to filter items based on a linked entry.

http://localhost/api/collections/news/entries?filter[categories:contains]=some-value

Response structure (unfiltered) looks like this:

data": [
  {
    "blueprint": {
    "title": "News",
    "handle": "news"
  },
  "categories": {
    "type": {
      "id": "c3f098dd-74d2-4c8f-8daf-a6d1f0fa72fe",
      "title": "Some Value",
      "slug": "some-value",
      "url": "[/news/ankuendigung](http://localhost/news/some-value)",
      "permalink": "http://localhost:3000/news/some-value"
    },
    [...]
  },
}

With the filter, I get no results.

On the other hand, filtering for taxonomies does work.