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Author: carlosdelest

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/KnnSemanticTextTestCase.java

@@ -27,6 +27,9 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.core.StringContains.containsString;
 
+/**
+ * Tests kNN queries on semantic_text fields. Mostly checks errors on the data node that can't be checked in other tests.
+ */
 public class KnnSemanticTextTestCase extends ESRestTestCase {
 
     @Rule(order = Integer.MIN_VALUE)

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/vector/Knn.java

@@ -213,6 +213,7 @@ protected TypeResolution resolveParams() {
 
     private TypeResolution resolveField() {
         return isNotNull(field(), sourceText(), FIRST).and(
+            // It really should be semantic_text instead of text, but field_caps retrieves semantic_text fields as text
             isType(field(), dt -> dt == TEXT, sourceText(), FIRST, ACCEPTED_FIELD_TYPES).or(
                 isType(field(), dt -> dt == DENSE_VECTOR, sourceText(), FIRST, ACCEPTED_FIELD_TYPES)
             )