diff --git a/ml-algorithms/src/main/java/org/opensearch/ml/engine/tools/MLModelTool.java b/ml-algorithms/src/main/java/org/opensearch/ml/engine/tools/MLModelTool.java
index cba0d2ee6a..8a33edca7d 100644
--- a/ml-algorithms/src/main/java/org/opensearch/ml/engine/tools/MLModelTool.java
+++ b/ml-algorithms/src/main/java/org/opensearch/ml/engine/tools/MLModelTool.java
@@ -34,6 +34,9 @@
 @ToolAnnotation(MLModelTool.TYPE)
 public class MLModelTool implements Tool {
     public static final String TYPE = "MLModelTool";
+    public static final String RESPONSE_FIELD = "response_field";
+    public static final String MODEL_ID_FIELD = "model_id";
+    public static final String DEFAULT_RESPONSE_FIELD = "response";
 
     @Setter
     @Getter
@@ -52,14 +55,18 @@ public class MLModelTool implements Tool {
     @Setter
     @Getter
     private Parser outputParser;
+    @Setter
+    @Getter
+    private String responseField;
 
-    public MLModelTool(Client client, String modelId) {
+    public MLModelTool(Client client, String modelId, String responseField) {
         this.client = client;
         this.modelId = modelId;
+        this.responseField = responseField;
 
         outputParser = o -> {
             List<ModelTensors> mlModelOutputs = (List<ModelTensors>) o;
-            return mlModelOutputs.get(0).getMlModelTensors().get(0).getDataAsMap().get("response");
+            return mlModelOutputs.get(0).getMlModelTensors().get(0).getDataAsMap().get(responseField);
         };
     }
 
@@ -132,7 +139,11 @@ public void init(Client client) {
 
         @Override
         public MLModelTool create(Map<String, Object> map) {
-            return new MLModelTool(client, (String) map.get("model_id"));
+            return new MLModelTool(
+                client,
+                (String) map.get(MODEL_ID_FIELD),
+                (String) map.getOrDefault(RESPONSE_FIELD, DEFAULT_RESPONSE_FIELD)
+            );
         }
 
         @Override
diff --git a/ml-algorithms/src/test/java/org/opensearch/ml/engine/tools/MLModelToolTests.java b/ml-algorithms/src/test/java/org/opensearch/ml/engine/tools/MLModelToolTests.java
index e4bcb9db5d..f6b54b56be 100644
--- a/ml-algorithms/src/test/java/org/opensearch/ml/engine/tools/MLModelToolTests.java
+++ b/ml-algorithms/src/test/java/org/opensearch/ml/engine/tools/MLModelToolTests.java
@@ -5,13 +5,22 @@
 
 package org.opensearch.ml.engine.tools;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.Mockito.*;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.verify;
 import static org.opensearch.ml.engine.tools.MLModelTool.DEFAULT_DESCRIPTION;
 
-import java.util.*;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -53,7 +62,73 @@ public void setup() {
     }
 
     @Test
-    public void testMLModelsWithOutputParser() {
+    public void testMLModelsWithDefaultOutputParserAndDefaultResponseField() throws ExecutionException, InterruptedException {
+        ModelTensor modelTensor = ModelTensor.builder().dataAsMap(ImmutableMap.of("response", "response 1", "action", "action1")).build();
+        ModelTensors modelTensors = ModelTensors.builder().mlModelTensors(Arrays.asList(modelTensor)).build();
+        ModelTensorOutput mlModelTensorOutput = ModelTensorOutput.builder().mlModelOutputs(Arrays.asList(modelTensors)).build();
+        doAnswer(invocation -> {
+
+            ActionListener<MLTaskResponse> actionListener = invocation.getArgument(2);
+
+            actionListener.onResponse(MLTaskResponse.builder().output(mlModelTensorOutput).build());
+            return null;
+        }).when(client).execute(eq(MLPredictionTaskAction.INSTANCE), any(), any());
+
+        Tool tool = MLModelTool.Factory.getInstance().create(Map.of("model_id", "modelId"));
+        final CompletableFuture<String> future = new CompletableFuture<>();
+        ActionListener<String> listener = ActionListener.wrap(r -> { future.complete(r); }, e -> { future.completeExceptionally(e); });
+        tool.run(null, listener);
+
+        future.join();
+        assertEquals("response 1", future.get());
+    }
+
+    @Test
+    public void testMLModelsWithDefaultOutputParserAndCustomizedResponseField() throws ExecutionException, InterruptedException {
+        ModelTensor modelTensor = ModelTensor.builder().dataAsMap(ImmutableMap.of("response", "response 1", "action", "action1")).build();
+        ModelTensors modelTensors = ModelTensors.builder().mlModelTensors(Arrays.asList(modelTensor)).build();
+        ModelTensorOutput mlModelTensorOutput = ModelTensorOutput.builder().mlModelOutputs(Arrays.asList(modelTensors)).build();
+        doAnswer(invocation -> {
+
+            ActionListener<MLTaskResponse> actionListener = invocation.getArgument(2);
+
+            actionListener.onResponse(MLTaskResponse.builder().output(mlModelTensorOutput).build());
+            return null;
+        }).when(client).execute(eq(MLPredictionTaskAction.INSTANCE), any(), any());
+
+        Tool tool = MLModelTool.Factory.getInstance().create(Map.of("model_id", "modelId", "response_field", "action"));
+        final CompletableFuture<String> future = new CompletableFuture<>();
+        ActionListener<String> listener = ActionListener.wrap(r -> { future.complete(r); }, e -> { future.completeExceptionally(e); });
+        tool.run(null, listener);
+
+        future.join();
+        assertEquals("action1", future.get());
+    }
+
+    @Test
+    public void testMLModelsWithDefaultOutputParserAndMalformedResponseField() throws ExecutionException, InterruptedException {
+        ModelTensor modelTensor = ModelTensor.builder().dataAsMap(ImmutableMap.of("response", "response 1", "action", "action1")).build();
+        ModelTensors modelTensors = ModelTensors.builder().mlModelTensors(Arrays.asList(modelTensor)).build();
+        ModelTensorOutput mlModelTensorOutput = ModelTensorOutput.builder().mlModelOutputs(Arrays.asList(modelTensors)).build();
+        doAnswer(invocation -> {
+
+            ActionListener<MLTaskResponse> actionListener = invocation.getArgument(2);
+
+            actionListener.onResponse(MLTaskResponse.builder().output(mlModelTensorOutput).build());
+            return null;
+        }).when(client).execute(eq(MLPredictionTaskAction.INSTANCE), any(), any());
+
+        Tool tool = MLModelTool.Factory.getInstance().create(Map.of("model_id", "modelId", "response_field", "malformed field"));
+        final CompletableFuture<String> future = new CompletableFuture<>();
+        ActionListener<String> listener = ActionListener.wrap(r -> { future.complete(r); }, e -> { future.completeExceptionally(e); });
+        tool.run(null, listener);
+
+        future.join();
+        assertEquals(null, future.get());
+    }
+
+    @Test
+    public void testMLModelsWithCustomizedOutputParser() {
         ModelTensor modelTensor = ModelTensor.builder().dataAsMap(ImmutableMap.of("thought", "thought 1", "action", "action1")).build();
         ModelTensors modelTensors = ModelTensors.builder().mlModelTensors(Arrays.asList(modelTensor)).build();
         ModelTensorOutput mlModelTensorOutput = ModelTensorOutput.builder().mlModelOutputs(Arrays.asList(modelTensors)).build();