diff --git a/packages/cli/src/config/config.ts b/packages/cli/src/config/config.ts
index 30614082..e6f8d423 100644
--- a/packages/cli/src/config/config.ts
+++ b/packages/cli/src/config/config.ts
@@ -226,7 +226,7 @@ export async function loadCliConfig(
         process.env.OTEL_EXPORTER_OTLP_ENDPOINT ??
         settings.telemetry?.otlpEndpoint,
       logPrompts: argv.telemetryLogPrompts ?? settings.telemetry?.logPrompts,
-      disableDataCollection: settings.telemetry?.disableDataCollection ?? true,
+      disableDataCollection: settings.telemetry?.disableDataCollection ?? false,
     },
     // Git-aware file filtering settings
     fileFiltering: {
diff --git a/packages/core/src/config/config.ts b/packages/core/src/config/config.ts
index a9696206..d9161fae 100644
--- a/packages/core/src/config/config.ts
+++ b/packages/core/src/config/config.ts
@@ -117,7 +117,6 @@ export interface ConfigParameters {
   fileDiscoveryService?: FileDiscoveryService;
   bugCommand?: BugCommandSettings;
   model: string;
-  disableDataCollection?: boolean;
   extensionContextFilePaths?: string[];
 }
 
@@ -155,7 +154,6 @@ export class Config {
   private readonly cwd: string;
   private readonly bugCommand: BugCommandSettings | undefined;
   private readonly model: string;
-  private readonly disableDataCollection: boolean;
   private readonly extensionContextFilePaths: string[];
 
   constructor(params: ConfigParameters) {
@@ -183,6 +181,7 @@ export class Config {
       target: params.telemetry?.target ?? DEFAULT_TELEMETRY_TARGET,
       otlpEndpoint: params.telemetry?.otlpEndpoint ?? DEFAULT_OTLP_ENDPOINT,
       logPrompts: params.telemetry?.logPrompts ?? true,
+      disableDataCollection: params.telemetry?.disableDataCollection ?? false,
     };
 
     this.fileFiltering = {
@@ -196,8 +195,6 @@ export class Config {
     this.fileDiscoveryService = params.fileDiscoveryService ?? null;
     this.bugCommand = params.bugCommand;
     this.model = params.model;
-    this.disableDataCollection =
-      params.telemetry?.disableDataCollection ?? true;
     this.extensionContextFilePaths = params.extensionContextFilePaths ?? [];
 
     if (params.contextFileName) {
@@ -208,10 +205,12 @@ export class Config {
       initializeTelemetry(this);
     }
 
-    if (!this.disableDataCollection) {
-      ClearcutLogger.getInstance(this)?.enqueueLogEvent(
+    if (!this.getDisableDataCollection()) {
+      ClearcutLogger.getInstance(this)?.logStartSessionEvent(
         new StartSessionEvent(this),
       );
+    } else {
+      console.log('Data collection is disabled.');
     }
   }
 
@@ -387,7 +386,7 @@ export class Config {
   }
 
   getDisableDataCollection(): boolean {
-    return this.disableDataCollection;
+    return this.telemetrySettings.disableDataCollection ?? false;
   }
 
   getExtensionContextFilePaths(): string[] {
diff --git a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
index 8da928c7..aa4afe4c 100644
--- a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
+++ b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
@@ -64,7 +64,7 @@ export class ClearcutLogger {
     ]);
   }
 
-  createLogEvent(name: string, data: Map<EventMetadataKey, string>): object {
+  createLogEvent(name: string, data: object): object {
     return {
       Application: 'GEMINI_CLI',
       event_name: name,
@@ -83,6 +83,7 @@ export class ClearcutLogger {
   }
 
   flushToClearcut(): Promise<LogResponse> {
+    console.log('Flushing log events to Clearcut.');
     return new Promise<Buffer>((resolve, reject) => {
       const request = [
         {
@@ -92,6 +93,7 @@ export class ClearcutLogger {
         },
       ];
       const body = JSON.stringify(request);
+      console.log('Clearcut POST request body:', body);
       const options = {
         hostname: 'play.googleapis.com',
         path: '/log',
@@ -106,6 +108,7 @@ export class ClearcutLogger {
         });
       });
       req.on('error', (e) => {
+        console.log('Clearcut POST request error: ', e);
         reject(e);
       });
       req.end(body);
@@ -152,58 +155,81 @@ export class ClearcutLogger {
       // message is corrupted.
       return undefined;
     }
-    return {
+
+    const returnVal = {
       nextRequestWaitMs: Number(ms),
     };
+    console.log('Clearcut response: ', returnVal);
+    return returnVal;
   }
 
   logStartSessionEvent(event: StartSessionEvent): void {
-    const data: Map<EventMetadataKey, string> = new Map();
-
-    data.set(EventMetadataKey.GEMINI_CLI_START_SESSION_MODEL, event.model);
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_EMBEDDING_MODEL,
-      event.embedding_model,
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_SANDBOX,
-      event.sandbox_enabled.toString(),
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_CORE_TOOLS,
-      event.core_tools_enabled,
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_APPROVAL_MODE,
-      event.approval_mode,
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_API_KEY_ENABLED,
-      event.api_key_enabled.toString(),
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_VERTEX_API_ENABLED,
-      event.vertex_ai_enabled.toString(),
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_DEBUG_MODE_ENABLED,
-      event.debug_enabled.toString(),
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_MCP_SERVERS,
-      event.mcp_servers,
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_TELEMETRY_ENABLED,
-      event.telemetry_enabled.toString(),
-    );
-    data.set(
-      EventMetadataKey.GEMINI_CLI_START_SESSION_TELEMETRY_LOG_USER_PROMPTS_ENABLED,
-      event.telemetry_log_user_prompts_enabled.toString(),
-    );
-
+    const data = [
+      {
+        EventMetadataKey: EventMetadataKey.GEMINI_CLI_START_SESSION_MODEL,
+        value: event.model,
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_EMBEDDING_MODEL,
+        value: event.embedding_model,
+      },
+      {
+        EventMetadataKey: EventMetadataKey.GEMINI_CLI_START_SESSION_SANDBOX,
+        value: event.sandbox_enabled.toString(),
+      },
+      {
+        EventMetadataKey: EventMetadataKey.GEMINI_CLI_START_SESSION_CORE_TOOLS,
+        value: event.core_tools_enabled,
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_APPROVAL_MODE,
+        value: event.approval_mode,
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_API_KEY_ENABLED,
+        value: event.api_key_enabled.toString(),
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_VERTEX_API_ENABLED,
+        value: event.vertex_ai_enabled.toString(),
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_DEBUG_MODE_ENABLED,
+        value: event.debug_enabled.toString(),
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_VERTEX_API_ENABLED,
+        value: event.vertex_ai_enabled.toString(),
+      },
+      {
+        EventMetadataKey: EventMetadataKey.GEMINI_CLI_START_SESSION_MCP_SERVERS,
+        value: event.mcp_servers,
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_VERTEX_API_ENABLED,
+        value: event.vertex_ai_enabled.toString(),
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_TELEMETRY_ENABLED,
+        value: event.telemetry_enabled.toString(),
+      },
+      {
+        EventMetadataKey:
+          EventMetadataKey.GEMINI_CLI_START_SESSION_TELEMETRY_LOG_USER_PROMPTS_ENABLED,
+        value: event.telemetry_log_user_prompts_enabled.toString(),
+      },
+    ];
     this.enqueueLogEvent(this.createLogEvent(start_session_event_name, data));
-    this.flushIfNeeded();
+    // Flush start event immediately
+    this.flushToClearcut();
   }
 
   logNewPromptEvent(event: UserPromptEvent): void {