diff --git a/tests/test_cdp_browser.py b/tests/test_cdp_browser.py
new file mode 100644
index 0000000..66a4b3f
--- /dev/null
+++ b/tests/test_cdp_browser.py
@@ -0,0 +1,95 @@
+# -*- coding: utf-8 -*-
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+
+import config
+from tools.cdp_browser import CDPBrowserManager
+
+
+@pytest.mark.asyncio
+async def test_existing_browser_connects_directly_to_devtools_browser(monkeypatch):
+    monkeypatch.setattr(config, "CDP_CONNECT_EXISTING", True)
+    monkeypatch.setattr(config, "BROWSER_LAUNCH_TIMEOUT", 60)
+
+    manager = CDPBrowserManager()
+    manager.debug_port = 9222
+    manager._get_browser_websocket_url = AsyncMock(  # type: ignore[method-assign]
+        side_effect=AssertionError("existing browser mode must not call /json/version")
+    )
+
+    browser = MagicMock()
+    browser.is_connected.return_value = True
+    browser.contexts = []
+
+    playwright = MagicMock()
+    playwright.chromium.connect_over_cdp = AsyncMock(return_value=browser)
+
+    await manager._connect_via_cdp(playwright)
+
+    playwright.chromium.connect_over_cdp.assert_awaited_once_with(
+        "ws://localhost:9222/devtools/browser",
+        timeout=60000,
+    )
+
+
+@pytest.mark.asyncio
+async def test_existing_browser_falls_back_to_discovered_websocket_url(monkeypatch):
+    monkeypatch.setattr(config, "CDP_CONNECT_EXISTING", True)
+    monkeypatch.setattr(config, "BROWSER_LAUNCH_TIMEOUT", 60)
+
+    manager = CDPBrowserManager()
+    manager.debug_port = 9222
+    manager._get_browser_websocket_url = AsyncMock(  # type: ignore[method-assign]
+        return_value="ws://localhost:9222/devtools/browser/generated-id"
+    )
+
+    browser = MagicMock()
+    browser.is_connected.return_value = True
+    browser.contexts = []
+
+    playwright = MagicMock()
+    playwright.chromium.connect_over_cdp = AsyncMock(
+        side_effect=[RuntimeError("direct websocket failed"), browser]
+    )
+
+    await manager._connect_via_cdp(playwright)
+
+    manager._get_browser_websocket_url.assert_awaited_once_with(9222)
+    assert playwright.chromium.connect_over_cdp.await_args_list[0].args == (
+        "ws://localhost:9222/devtools/browser",
+    )
+    assert playwright.chromium.connect_over_cdp.await_args_list[0].kwargs == {
+        "timeout": 60000,
+    }
+    assert playwright.chromium.connect_over_cdp.await_args_list[1].args == (
+        "ws://localhost:9222/devtools/browser/generated-id",
+    )
+    assert playwright.chromium.connect_over_cdp.await_args_list[1].kwargs == {
+        "timeout": 60000,
+    }
+
+
+@pytest.mark.asyncio
+async def test_launched_browser_uses_discovered_websocket_url(monkeypatch):
+    monkeypatch.setattr(config, "CDP_CONNECT_EXISTING", False)
+
+    manager = CDPBrowserManager()
+    manager.debug_port = 9223
+    manager._get_browser_websocket_url = AsyncMock(  # type: ignore[method-assign]
+        return_value="ws://localhost:9223/devtools/browser/generated-id"
+    )
+
+    browser = MagicMock()
+    browser.is_connected.return_value = True
+    browser.contexts = []
+
+    playwright = MagicMock()
+    playwright.chromium.connect_over_cdp = AsyncMock(return_value=browser)
+
+    await manager._connect_via_cdp(playwright)
+
+    manager._get_browser_websocket_url.assert_awaited_once_with(9223)
+    playwright.chromium.connect_over_cdp.assert_awaited_once_with(
+        "ws://localhost:9223/devtools/browser/generated-id"
+    )
diff --git a/tools/cdp_browser.py b/tools/cdp_browser.py
index c6d76b9..bc5a76c 100644
--- a/tools/cdp_browser.py
+++ b/tools/cdp_browser.py
@@ -316,16 +316,29 @@ class CDPBrowserManager:
         """
         try:
             if config.CDP_CONNECT_EXISTING:
-                # Existing Chrome exposes the browser websocket URL from /json/version.
-                # Newer Chrome versions return a UUID path instead of plain /devtools/browser.
-                ws_url = await self._get_browser_websocket_url(self.debug_port)
+                # Existing browser remote debugging in Chrome 136+ does not expose
+                # /json/version. Connect directly and wait for user confirmation.
+                ws_url = f"ws://localhost:{self.debug_port}/devtools/browser"
                 utils.logger.info(f"[CDPBrowserManager] Connecting to existing browser via CDP: {ws_url}")
                 utils.logger.info(
                     "[CDPBrowserManager] Please check your browser for a confirmation dialog and accept it"
                 )
-                self.browser = await playwright.chromium.connect_over_cdp(
-                    ws_url, timeout=config.BROWSER_LAUNCH_TIMEOUT * 1000
-                )
+                try:
+                    self.browser = await playwright.chromium.connect_over_cdp(
+                        ws_url, timeout=config.BROWSER_LAUNCH_TIMEOUT * 1000
+                    )
+                except Exception as direct_error:
+                    utils.logger.warning(
+                        "[CDPBrowserManager] Direct existing-browser CDP connection failed: "
+                        f"{direct_error}. Trying /json/version discovery..."
+                    )
+                    ws_url = await self._get_browser_websocket_url(self.debug_port)
+                    utils.logger.info(
+                        f"[CDPBrowserManager] Connecting to existing browser via discovered CDP: {ws_url}"
+                    )
+                    self.browser = await playwright.chromium.connect_over_cdp(
+                        ws_url, timeout=config.BROWSER_LAUNCH_TIMEOUT * 1000
+                    )
             else:
                 # For launched browser, get WebSocket URL first
                 ws_url = await self._get_browser_websocket_url(self.debug_port)