fix: Handle optional request body in reset endpoint and set default task ID

server/app.py

@@ -156,16 +156,25 @@ def list_tasks():
     ]
     return {"tasks": [t.model_dump() for t in tasks]}
 
-
 @app.post("/reset")
 def reset(
-    body: ResetRequest,
+    body: Optional[ResetRequest] = None,
     session_id: str = Query(default=DEFAULT_SESSION),
 ):
     """Reset the environment and start a new episode."""
-    env = _create_env(body.task_id)
+    
+    # Handle missing body (OpenEnv validator case)
+    if body is None:
+        task_id = "task1_vuln_detection"
+        seed = None
+    else:
+        task_id = body.task_id
+        seed = body.seed
+
+    env = _create_env(task_id)
     _sessions[session_id] = env
-    result = env.reset(seed=body.seed)
+
+    result = env.reset(seed=seed)
     return JSONResponse(content=result.model_dump(), status_code=200)