diff --git a/parallel_orchestrator.py b/parallel_orchestrator.py
index fc7fe7a..419e093 100644
--- a/parallel_orchestrator.py
+++ b/parallel_orchestrator.py
@@ -194,6 +194,7 @@ class ParallelOrchestrator:
         # Legacy alias for backward compatibility
         self.running_agents = self.running_coding_agents
         self.abort_events: dict[int, threading.Event] = {}
+        self._testing_session_counter = 0
         self.is_running = False
 
         # Track feature failures to prevent infinite retry loops
@@ -846,7 +847,7 @@ class ParallelOrchestrator:
                 "encoding": "utf-8",
                 "errors": "replace",
                 "cwd": str(self.project_dir),  # Run from project dir so CLI creates .claude/ in project
-                "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": ""},
+                "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": "", "PLAYWRIGHT_CLI_SESSION": f"coding-{feature_id}"},
             }
             if sys.platform == "win32":
                 popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW
@@ -909,7 +910,7 @@ class ParallelOrchestrator:
                 "encoding": "utf-8",
                 "errors": "replace",
                 "cwd": str(self.project_dir),  # Run from project dir so CLI creates .claude/ in project
-                "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": ""},
+                "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": "", "PLAYWRIGHT_CLI_SESSION": f"coding-{primary_id}"},
             }
             if sys.platform == "win32":
                 popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW
@@ -1013,8 +1014,9 @@ class ParallelOrchestrator:
                     "encoding": "utf-8",
                     "errors": "replace",
                     "cwd": str(self.project_dir),  # Run from project dir so CLI creates .claude/ in project
-                    "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": ""},
+                    "env": {**os.environ, "PYTHONUNBUFFERED": "1", "NODE_COMPILE_CACHE": "", "PLAYWRIGHT_CLI_SESSION": f"testing-{self._testing_session_counter}"},
                 }
+                self._testing_session_counter += 1
                 if sys.platform == "win32":
                     popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW