diff --git a/aiia_cosyvoice_nodes.py b/aiia_cosyvoice_nodes.py
index b196e32..0b74fa2 100644
--- a/aiia_cosyvoice_nodes.py
+++ b/aiia_cosyvoice_nodes.py
@@ -483,7 +483,7 @@ class AIIA_CosyVoice_TTS:
                 "model": ("COSYVOICE_MODEL",),
                 "tts_text": ("STRING", {"multiline": True, "default": "你好，这是 CosyVoice 3.0 的全能模式测试。"}),
                 "instruct_text": ("STRING", {"multiline": True, "default": "一个沉稳、磁性的成熟男性声音，语法标准，情感饱满。"}),
-                "spk_id": ("STRING", {"default": "pure_1", "tooltip": "V1/V2 时代的固定 ID，如 pure_1, joy_1 等。如果提供参考音频且非 SFT 模型，此项可能被忽略。"}),
+                "spk_id": ("STRING", {"default": "", "tooltip": "固定音色 ID (如 pure_1)。对于 0.5B/V3 等 Zero-Shot 模型，此项通常为空，需配合参考音频使用。"}),
                 "speed": ("FLOAT", {"default": 1.0, "min": 0.5, "max": 2.0, "step": 0.1}),
                 "seed": ("INT", {"default": 42, "min": -1, "max": 2147483647}),
             },
@@ -512,7 +512,24 @@ class AIIA_CosyVoice_TTS:
             is_v3 = "CosyVoice3" in type(cosyvoice_model).__name__
             is_v2 = "CosyVoice2" in type(cosyvoice_model).__name__
 
-            # 1. Hybrid / Cross-Lingual / Zero-Shot (Reference Audio provided)
+            # 1. Identity Validation
+            available_spks = list(cosyvoice_model.frontend.spk2info.keys())
+            
+            # Case A: User specified a Speaker ID
+            if spk_id:
+                if spk_id not in available_spks:
+                    raise ValueError(f"Speaker ID '{spk_id}' not found. Available: {available_spks if available_spks else 'None (Zero-Shot model)'}")
+            
+            # Case B: No ID and no Audio
+            elif reference_audio is None:
+                if available_spks:
+                    spk_id = available_spks[0]
+                    print(f"[AIIA] Auto-selecting first available speaker: {spk_id}")
+                else:
+                    # 0.5B models typically have no spk2info
+                    raise ValueError("此模型 (CosyVoice 0.5B/V3) 没有内置音色库。请连接 'reference_audio' 进行零样本克隆或生成。")
+
+            # 2. Hybrid / Cross-Lingual / Zero-Shot (Reference Audio provided)
             if reference_audio is not None:
                 ref_wav = reference_audio["waveform"]
                 if reference_audio["sample_rate"] != sample_rate:
@@ -529,20 +546,17 @@ class AIIA_CosyVoice_TTS:
                 
                 try:
                     if is_v3 or is_v2:
-                        # V3/V2: Support Instruct + Audio (Hybrid Mode)
                         print(f"[AIIA] CosyVoice V3/V2: Hybrid/Zero-Shot Mode. Instruct: {instruct_text[:20]}...")
                         output = cosyvoice_model.inference_instruct2(
                             tts_text=tts_text, 
                             instruct_text=instruct_text, 
                             prompt_wav=ref_path, 
-                            zero_shot_spk_id=spk_id, # Optional placeholder
+                            zero_shot_spk_id=spk_id, 
                             stream=False, 
                             speed=speed
                         )
                     else:
-                        # V1: Source-Prompt based inference
                         print("[AIIA] CosyVoice V1: Zero-Shot / Cross-Lingual Mode")
-                        # Some versions use inference_vc or inference_zero_shot
                         if hasattr(cosyvoice_model, 'inference_zero_shot'):
                              output = cosyvoice_model.inference_zero_shot(tts_text, ref_path, stream=False, speed=speed)
                         else:
@@ -553,11 +567,10 @@ class AIIA_CosyVoice_TTS:
                 finally:
                     if os.path.exists(ref_path): os.unlink(ref_path)
 
-            # 2. Instruct / SFT / Random (No Reference Audio)
+            # 3. Instruct / SFT / Random (No Reference Audio, verified we have spk_id)
             else:
                 if is_v3 or is_v2:
                     print(f"[AIIA] CosyVoice V3/V2: Instruct Generation. Description: {instruct_text[:20]}...")
-                    # For pure generation in V3, prompt_wav can be None
                     output = cosyvoice_model.inference_instruct2(
                         tts_text=tts_text, 
                         instruct_text=instruct_text, 
@@ -567,7 +580,6 @@ class AIIA_CosyVoice_TTS:
                         speed=speed
                     )
                 else:
-                    # V1 SFT / Instruct
                     print(f"[AIIA] CosyVoice V1: SFT/Instruct. Speaker ID: {spk_id}")
                     if "SFT" in type(cosyvoice_model).__name__ or spk_id:
                         output = cosyvoice_model.inference_sft(tts_text, spk_id, stream=False, speed=speed)
@@ -578,6 +590,7 @@ class AIIA_CosyVoice_TTS:
                 final_waveform = torch.cat(all_speech, dim=-1)
 
         except Exception as e:
+            if isinstance(e, ValueError): raise e
             raise RuntimeError(f"CosyVoice generation failed: {e}")
 
         return ({"waveform": final_waveform.unsqueeze(0).cpu(), "sample_rate": sample_rate},)