Only shards in suggest query response?

Elastic Stack Elasticsearch
1

edit: I don't know what was happening here, but something I've done since has fixed the issue. Feel free to ignore.

If I make something like the following query:

GET foobar/_suggest
{
  "animal": {
    "text": "foo",
    "completion": {
      "field": "suggest"
    }
  }
}

This is the only response I'm getting back:

{
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  }
}

Am I making some sort of mistake with the query, or is this a sign of some other problem?