diff --git a/docs/ppl-lang/functions/ppl-json.md b/docs/ppl-lang/functions/ppl-json.md
index 27cc33d30..627eb110c 100644
--- a/docs/ppl-lang/functions/ppl-json.md
+++ b/docs/ppl-lang/functions/ppl-json.md
@@ -269,7 +269,7 @@ Example:
     | {"a":["valueA", "valueB", "valueC"]}            |
     +-------------------------------------------------+
 
-    os> source=people | eval append = json_append(`{"a":["valueA", "valueB"]}`, {"a":["valueC"]}) 
+    os> source=people | eval append = json_append(`{"a":["valueA", "valueB"]}`, ['a', {"a":["valueC"]}]) 
     fetched rows / total rows = 1/1
     +-----------------------------------------------+
     | append                                        |
@@ -304,7 +304,7 @@ Extend arrays as individual values separates the `json_extend` functionality fro
 
 Example:
 
-    os> source=people | eval extend = json_extend(`{"a":["valueA", "valueB"]}`, ["valueC","valueD"]) 
+    os> source=people | eval extend = json_extend(`{"a":["valueA", "valueB"]}`,['a', ["valueC","valueD"]]) 
     fetched rows / total rows = 1/1
     +-------------------------------------------------+
     | extend                                          |
@@ -312,7 +312,7 @@ Example:
     | {"a":["valueA", "valueB", "valueC", "valueD"]}  |
     +-------------------------------------------------+
 
-    os> source=people | eval extend = json_extend(`{"a":["valueA", "valueB"]}`, {"b":["valueC","valueD"]}) 
+    os> source=people | eval extend = json_extend(`{"a":["valueA", "valueB"]}`,['a',[{"b":["valueC","valueD"]}]]) 
     fetched rows / total rows = 1/1
     +-------------------------------------------------------------+
     | extend                                                      |
diff --git a/ppl-spark-integration/src/test/java/org/opensearch/sql/expression/function/SerializableJsonUdfTest.java b/ppl-spark-integration/src/test/java/org/opensearch/sql/expression/function/SerializableJsonUdfTest.java
index 2c7080622..996569611 100644
--- a/ppl-spark-integration/src/test/java/org/opensearch/sql/expression/function/SerializableJsonUdfTest.java
+++ b/ppl-spark-integration/src/test/java/org/opensearch/sql/expression/function/SerializableJsonUdfTest.java
@@ -183,4 +183,70 @@ public void testJsonExtendFunctionWithNonArrayPath() {
 
         assertEquals(expectedJson, result);
     }
+
+    @Test
+    public void testJsonExtendFunctionAddValuesToExistingArray() {
+        // Initial JSON string
+        String jsonStr = "{\"key1\":\"value1\",\"key2\":[\"value2\"]}";
+
+        // Path-value pairs to extend
+        List<Map.Entry<String, List<String>>> pathValuePairs = new ArrayList<>();
+        pathValuePairs.add( Map.entry("key2", Arrays.asList("value3", "value4")));
+
+        // Expected JSON after extension
+        String expectedJson = "{\"key1\":\"value1\",\"key2\":[\"value2\",\"value3\",\"value4\"]}";
+
+        // Apply the function
+        String result = jsonExtendFunction.apply(jsonStr, pathValuePairs);
+
+        // Assert that the result matches the expected JSON
+        assertEquals(expectedJson, result);
+    }
+
+    @Test
+    public void testJsonExtendFunctionAddNewArray() {
+        // Initial JSON string
+        String jsonStr = "{\"key1\":\"value1\"}";
+
+        // Path-value pairs to add
+        List<Map.Entry<String, List<String>>> pathValuePairs = new ArrayList<>();
+        pathValuePairs.add( Map.entry("key2", Arrays.asList("value2", "value3")));
+
+        // Expected JSON after adding new array
+        String expectedJson = "{\"key1\":\"value1\",\"key2\":[\"value2\",\"value3\"]}";
+
+        // Apply the function
+        String result = jsonExtendFunction.apply(jsonStr, pathValuePairs);
+
+        // Assert that the result matches the expected JSON
+        assertEquals(expectedJson, result);
+    }
+
+    @Test
+    public void testJsonExtendFunctionHandleEmptyValues() {
+        // Initial JSON string
+        String jsonStr = "{\"key1\":\"value1\",\"key2\":[\"value2\"]}";
+
+        // Path-value pairs with an empty list of values to add
+        List<Map.Entry<String, List<String>>> pathValuePairs = new ArrayList<>();
+        pathValuePairs.add( Map.entry("key2", Collections.emptyList()));
+
+        // Expected JSON should remain unchanged
+        String expectedJson = "{\"key1\":\"value1\",\"key2\":[\"value2\"]}";
+
+        // Apply the function
+        String result = jsonExtendFunction.apply(jsonStr, pathValuePairs);
+
+        // Assert that the result matches the expected JSON
+        assertEquals(expectedJson, result);
+    }
+
+    @Test
+    public void testJsonExtendFunctionHandleNullInput() {
+        // Apply the function with null input
+        String result = jsonExtendFunction.apply(null, Collections.singletonList( Map.entry("key2", List.of("value2"))));
+
+        // Assert that the result is null
+        assertEquals(null, result);
+    }
 }
diff --git a/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanJsonFunctionsTranslatorTestSuite.scala b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanJsonFunctionsTranslatorTestSuite.scala
index 34d0133e0..8e36395b3 100644
--- a/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanJsonFunctionsTranslatorTestSuite.scala
+++ b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanJsonFunctionsTranslatorTestSuite.scala
@@ -5,20 +5,21 @@
 
 package org.opensearch.flint.spark.ppl
 
+import java.util
+
 import org.opensearch.flint.spark.ppl.PlaneUtils.plan
+import org.opensearch.sql.expression.function.SerializableUdf
+import org.opensearch.sql.expression.function.SerializableUdf.visit
 import org.opensearch.sql.ppl.{CatalystPlanContext, CatalystQueryPlanVisitor}
+import org.opensearch.sql.ppl.utils.DataTypeTransformer.seq
 import org.scalatest.matchers.should.Matchers
+
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.sql.catalyst.analysis.{UnresolvedAttribute, UnresolvedFunction, UnresolvedRelation, UnresolvedStar}
 import org.apache.spark.sql.catalyst.expressions.{EqualTo, Literal}
 import org.apache.spark.sql.catalyst.plans.PlanTest
 import org.apache.spark.sql.catalyst.plans.logical.{Filter, Project}
 import org.apache.spark.sql.types.DataTypes
-import org.opensearch.sql.expression.function.SerializableUdf
-import org.opensearch.sql.expression.function.SerializableUdf.visit
-import org.opensearch.sql.ppl.utils.DataTypeTransformer.seq
-
-import java.util
 
 class PPLLogicalPlanJsonFunctionsTranslatorTestSuite
     extends SparkFunSuite
@@ -194,11 +195,11 @@ class PPLLogicalPlanJsonFunctionsTranslatorTestSuite
     val context = new CatalystPlanContext
     val logPlan =
       planTransformer.visit(
-        plan(pplParser, """source=t a = json_delete('{"a":[{"b":1},{"c":2}]}', ["a.b"])"""),
+        plan(pplParser, """source=t a = json_delete('{"a":[{"b":1},{"c":2}]}', '["a.b"]')"""),
         context)
 
     val table = UnresolvedRelation(Seq("t"))
-    val keysExpression = Literal("[a.b]")
+    val keysExpression = Literal("""["a.b"]""")
     val jsonObjExp = Literal("""{"a":[{"b":1},{"c":2}]}""")
     val jsonFunc = visit("json_delete", util.List.of(jsonObjExp, keysExpression))
     val filterExpr = EqualTo(UnresolvedAttribute("a"), jsonFunc)
@@ -208,18 +209,37 @@ class PPLLogicalPlanJsonFunctionsTranslatorTestSuite
     comparePlans(expectedPlan, logPlan, false)
   }
 
-
   test("test json_append()") {
     val context = new CatalystPlanContext
     val logPlan =
       planTransformer.visit(
-        plan(pplParser, """source=t a = json_append('{"a":[{"b":1},{"c":2}]}', 'a.b')"""),
+        plan(pplParser, """source=t a = json_append('{"a":[1,2]}', '["a",3]')"""),
+        context)
+
+    val table = UnresolvedRelation(Seq("t"))
+    val keysExpression = Literal("""["a",3]""")
+    val jsonObjExp = Literal("""{"a":[1,2]}""")
+    val jsonFunc = visit("json_append", util.List.of(jsonObjExp, keysExpression))
+    val filterExpr = EqualTo(UnresolvedAttribute("a"), jsonFunc)
+    val filterPlan = Filter(filterExpr, table)
+    val projectList = Seq(UnresolvedStar(None))
+    val expectedPlan = Project(projectList, filterPlan)
+    comparePlans(expectedPlan, logPlan, false)
+  }
+
+  test("test json_extend()") {
+    val context = new CatalystPlanContext
+    val logPlan =
+      planTransformer.visit(
+        plan(
+          pplParser,
+          """source=t a = json_extend('{"a":[{"b":1},{"c":2}]}', '["a",{"c":2}]')"""),
         context)
 
     val table = UnresolvedRelation(Seq("t"))
-    val keysExpression = Literal("a.b")
+    val keysExpression = Literal("""["a",{"c":2}]""")
     val jsonObjExp = Literal("""{"a":[{"b":1},{"c":2}]}""")
-    val jsonFunc = visit("json_delete", util.List.of(jsonObjExp, keysExpression))
+    val jsonFunc = visit("json_extend", util.List.of(jsonObjExp, keysExpression))
     val filterExpr = EqualTo(UnresolvedAttribute("a"), jsonFunc)
     val filterPlan = Filter(filterExpr, table)
     val projectList = Seq(UnresolvedStar(None))
diff --git a/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanParseCidrmatchTestSuite.scala b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanParseCidrmatchTestSuite.scala
index d14b0fee1..c8a8a67ad 100644
--- a/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanParseCidrmatchTestSuite.scala
+++ b/ppl-spark-integration/src/test/scala/org/opensearch/flint/spark/ppl/PPLLogicalPlanParseCidrmatchTestSuite.scala
@@ -7,16 +7,17 @@ package org.opensearch.flint.spark.ppl
 
 import org.opensearch.flint.spark.ppl.PlaneUtils.plan
 import org.opensearch.sql.expression.function.SerializableUdf
+import org.opensearch.sql.expression.function.SerializableUdf.visit
 import org.opensearch.sql.ppl.{CatalystPlanContext, CatalystQueryPlanVisitor}
 import org.opensearch.sql.ppl.utils.DataTypeTransformer.seq
 import org.scalatest.matchers.should.Matchers
+
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.sql.catalyst.analysis.{UnresolvedAttribute, UnresolvedFunction, UnresolvedRelation, UnresolvedStar}
 import org.apache.spark.sql.catalyst.expressions.{Alias, And, Ascending, CaseWhen, Descending, EqualTo, GreaterThan, Literal, NullsFirst, NullsLast, RegExpExtract, SortOrder}
 import org.apache.spark.sql.catalyst.plans.PlanTest
 import org.apache.spark.sql.catalyst.plans.logical._
 import org.apache.spark.sql.types.DataTypes
-import org.opensearch.sql.expression.function.SerializableUdf.visit
 
 class PPLLogicalPlanParseCidrmatchTestSuite
     extends SparkFunSuite