Generate docs for function

Author: carlosdelest

docs/reference/query-languages/esql/kibana/definition/functions/v_cosine.json

@@ -3,14 +3,17 @@
  similarityWithVectorField
  required_capability: cosine_vector_similarity_function
 
+// tag::vector-cosine-similarity[]
  from colors
  | where color != "black" 
- | eval similarity = round(v_cosine(rgb_vector, [0, 255, 255]), 3) 
+ | eval similarity = v_cosine(rgb_vector, [0, 255, 255]) 
  | sort similarity desc, color asc 
+// end::vector-cosine-similarity[]
  | limit 10
  | keep color, similarity
  ;
 
+// tag::vector-cosine-similarity-result[]
 color:text     | similarity:double
 cyan           | 1.0            
 teal           | 1.0            
@@ -22,6 +25,7 @@ honeydew       | 0.912
 mint cream     | 0.912          
 gainsboro      | 0.908          
 gray           | 0.908     
+// end::vector-cosine-similarity-result[] 
 ;
 
  similarityAsPartOfExpression

docs/reference/query-languages/esql/kibana/docs/functions/v_cosine.md

@@ -13,6 +13,7 @@
 import org.elasticsearch.xpack.esql.core.expression.function.scalar.BinaryScalarFunction;
 import org.elasticsearch.xpack.esql.core.tree.NodeInfo;
 import org.elasticsearch.xpack.esql.core.tree.Source;
+import org.elasticsearch.xpack.esql.expression.function.Example;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
@@ -35,6 +36,7 @@ public class CosineSimilarity extends VectorSimilarityFunction {
         returnType = "double",
         preview = true,
         description = "Calculates the cosine similarity between two dense_vectors.",
+        examples = { @Example(file = "vector-cosine-similarity", tag = "vector-cosine-similarity") },
         appliesTo = { @FunctionAppliesTo(lifeCycle = FunctionAppliesToLifecycle.DEVELOPMENT) }
     )
     public CosineSimilarity(