diff --git a/src/bin/chrome-devtools.ts b/src/bin/chrome-devtools.ts
index 9e549c0e..ea5db5d2 100644
--- a/src/bin/chrome-devtools.ts
+++ b/src/bin/chrome-devtools.ts
@@ -35,7 +35,7 @@ import {
   shieldLiteralArgs,
 } from '../config/cli-commands.js';
 import {commands} from '../config/cli-options.js';
-import {mcpOptions, getCliOptions} from '../config/mcp-options.js';
+import {getCliOptions} from '../config/mcp-options.js';
 
 import {ConfigParser} from '../config/ConfigParser.js';
 
@@ -263,7 +263,7 @@ for (const [commandName, commandDef] of Object.entries(commands)) {
           : Promise.resolve(undefined);
 
         if (!daemonRunning) {
-          await start(serializeArgs(mcpOptions, argv), sessionId);
+          await start([], sessionId);
         }
 
         const commandArgs: Record<string, unknown> = {};
diff --git a/tests/e2e/chrome-devtools-status.test.ts b/tests/e2e/chrome-devtools-status.test.ts
index 6dc5d3b8..2e44572e 100644
--- a/tests/e2e/chrome-devtools-status.test.ts
+++ b/tests/e2e/chrome-devtools-status.test.ts
@@ -38,4 +38,26 @@ describe('chrome-devtools', () => {
 
     await assertDaemonIsRunning(sessionId);
   });
+
+  it('does not forward emulate viewport tool arg to daemon startup flags on auto-start', async () => {
+    await assertDaemonIsNotRunning(sessionId);
+
+    const emulateResult = await runCli(
+      ['emulate', '1', '--viewport', '500x400x1'],
+      sessionId,
+    );
+    assert.strictEqual(
+      emulateResult.status,
+      0,
+      `emulate command failed: ${emulateResult.stderr}`,
+    );
+
+    const statusResult = await runCli(['status'], sessionId);
+    assert.strictEqual(
+      statusResult.status,
+      0,
+      `status command failed: ${statusResult.stderr}`,
+    );
+    assert.match(statusResult.stdout, /args=\["--viaCli"\]/);
+  });
 });