Currently if you add a field in the fields parameter with a wildcard, no fields will be added to the hits layer. The situation is even worst if the wildcard matches the field name of the geo_point or geo_shape field, in that case a ClassCastException is thrown.
x-pack/plugin/vector-tile/src/javaRestTest/java/org/elasticsearch/xpack/vectortile/VectorTileRestIT.java
if (tag.equals(thisTag)) {
                VectorTile.Tile.Value thisValue = layer.getValues(feature.getTags(i + 1));
                assertThat(value, Matchers.equalTo(thisValue.getSintValue()));
                return;
            }
        }
        fail("Could not find tag [" + tag + "]");
    }
    private void assertDoubleTag(VectorTile.Tile.Layer layer, VectorTile.Tile.Feature feature, String tag, double value) {
        for (int i = 0; i < feature.getTagsCount(); i += 2) {
            String thisTag = layer.getKeys(feature.getTags(i));
            if (tag.equals(thisTag)) {
                VectorTile.Tile.Value thisValue = layer.getValues(feature.getTags(i + 1));
                assertThat(value, Matchers.equalTo(thisValue.getDoubleValue()));
                return;
            }
        }
        fail("Could not find tag [" + tag + "]");
    }
    private void assertStringTag(VectorTile.Tile.Layer layer, VectorTile.Tile.Feature feature, String tag, String value) {
        for (int i = 0; i < feature.getTagsCount(); i += 2) {
            String thisTag = layer.getKeys(feature.getTags(i));
            if (tag.equals(thisTag)) {
                VectorTile.Tile.Value thisValue = layer.getValues(feature.getTags(i + 1));
                assertEquals(thisValue.getStringValue(), value);
                return;
            }
        }
        fail("Could not find tag [" + tag + "]");
    }