--- before/wechat_rpa/admin_backend.py
+++ wechat_rpa/admin_backend.py
@@ -1921,6 +1921,9 @@
         endpoint_mode = str(item.get("endpoint_mode") or "auto").strip().lower()
         if endpoint_mode not in model_protocol.ENDPOINT_MODES:
             raise ValueError(f"不支持的地址模式：{endpoint_mode}")
+        config_error = model_protocol.chat_config_error(kind, base_url, item.get("model") or "")
+        if config_error and item.get("enabled", True):
+            raise ValueError(config_error)
 
         with self.connect() as db:
             db.execute("BEGIN IMMEDIATE")
@@ -2720,6 +2723,12 @@
         headers["Authorization"] = f"Bearer {api_key}"
     started = time.perf_counter()
     try:
+        config_error = model_protocol.chat_config_error(
+            provider_type_value, str(config.get("api_base") or endpoint),
+            str(config.get("model") or ""),
+        )
+        if config_error:
+            raise ValueError(config_error)
         status, raw = _perform_http_request(
             endpoint,
             method=method,
@@ -2740,6 +2749,9 @@
                 429: "请求受限、余额不足或调用频率过高",
             }
             message = labels.get(status, f"模型服务返回 HTTP {status}")
+            # Ark may use HTTP 404 for a model which exists but is not activated.
+            if "has not activated the model" in detail.lower():
+                message = "账号尚未开通该模型服务，请在火山方舟控制台开通，并确认 API Key 所属账号和项目"
             if detail:
                 message += f"：{detail}"
             return {