Add mcp system indices to system index descriptor (opensearch-project#3922)

Signed-off-by: zane-neo <[email protected]>

Author: zane-neo

plugin/src/main/java/org/opensearch/ml/plugin/MachineLearningPlugin.java

@@ -5,6 +5,8 @@
 
 package org.opensearch.ml.plugin;
 
+import static org.opensearch.ml.common.CommonValue.MCP_SESSION_MANAGEMENT_INDEX;
+import static org.opensearch.ml.common.CommonValue.MCP_TOOLS_INDEX;
 import static org.opensearch.ml.common.CommonValue.ML_AGENT_INDEX;
 import static org.opensearch.ml.common.CommonValue.ML_CONFIG_INDEX;
 import static org.opensearch.ml.common.CommonValue.ML_CONNECTOR_INDEX;
@@ -1267,6 +1269,8 @@ public Collection<SystemIndexDescriptor> getSystemIndexDescriptors(Settings sett
         systemIndexDescriptors.add(new SystemIndexDescriptor(ML_MEMORY_META_INDEX, "ML Commons Memory Meta Index"));
         systemIndexDescriptors.add(new SystemIndexDescriptor(ML_MEMORY_MESSAGE_INDEX, "ML Commons Memory Message Index"));
         systemIndexDescriptors.add(new SystemIndexDescriptor(ML_STOP_WORDS_INDEX, "ML Commons Stop Words Index"));
+        systemIndexDescriptors.add(new SystemIndexDescriptor(MCP_SESSION_MANAGEMENT_INDEX, "ML Commons MCP session management Index"));
+        systemIndexDescriptors.add(new SystemIndexDescriptor(MCP_TOOLS_INDEX, "ML Commons MCP tools Index"));
         return systemIndexDescriptors;
     }