diff --git a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
index 36bee1fc0c..8fcc9e6fc3 100644
--- a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
+++ b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
@@ -564,6 +564,12 @@ export class ClearcutLogger {
         }
       }
     }
+    if (event.extension_id) {
+      data.push({
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_EXTENSION_ID,
+        value: event.extension_id,
+      });
+    }
 
     const logEvent = this.createLogEvent(EventNames.TOOL_CALL, data);
     this.enqueueLogEvent(logEvent);
@@ -779,6 +785,13 @@ export class ClearcutLogger {
       });
     }
 
+    if (event.extension_id) {
+      data.push({
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_EXTENSION_ID,
+        value: event.extension_id,
+      });
+    }
+
     this.enqueueLogEvent(this.createLogEvent(EventNames.SLASH_COMMAND, data));
     this.flushIfNeeded();
   }