diff --git a/fam-edge/src/fam_edge/model_adapters/gemini_adapter.py b/fam-edge/src/fam_edge/model_adapters/gemini_adapter.py
index 5cefb8e..12f9f35 100644
--- a/fam-edge/src/fam_edge/model_adapters/gemini_adapter.py
+++ b/fam-edge/src/fam_edge/model_adapters/gemini_adapter.py
@@ -98,7 +98,8 @@ class GeminiAdapter(BaseModelAdapter):
 
         prompt = self._build_video_prompt(known_members_context, event_start_time)
         try:
-            text = self._generate_video(file_uri, prompt, max_tokens=4096, temperature=0.2)
+            # 3 秒密度 + person_appearances 特征使输出 JSON 较大，max_tokens 需足够高防截断
+            text = self._generate_video(file_uri, prompt, max_tokens=16384, temperature=0.2)
             if text is None:
                 self._cb.record_failure()
                 return None
diff --git a/fam-edge/src/fam_edge/model_adapters/nvidia_adapter.py b/fam-edge/src/fam_edge/model_adapters/nvidia_adapter.py
index d77677e..7b3a79c 100644
--- a/fam-edge/src/fam_edge/model_adapters/nvidia_adapter.py
+++ b/fam-edge/src/fam_edge/model_adapters/nvidia_adapter.py
@@ -179,7 +179,7 @@ class NvidiaVisionAdapter(BaseModelAdapter):
                             "url": f"data:video/mp4;asset_id={asset_id}"}}
                     ]}],
                     temperature=0.2,
-                    max_tokens=4096,
+                    max_tokens=16384,
                     # NIM 扩展：控制视频采样帧数（部分模型支持）
                     extra_body={"media_io_kwargs": {"video": {"num_frames": 128}}},
                     timeout=model_timeout